The Flat Earth Society

Flat Earth Discussion Boards => Flat Earth Q&A => Topic started by: MuNotEpsilonNot on May 26, 2013, 04:31:52 PM

Title: Space Flight
Post by: MuNotEpsilonNot on May 26, 2013, 04:31:52 PM
I have a few specific questions that I couldn't seem to answer through wiki or previous forum questions.

1) What is considered space flight? At what altitude or layer of the atmosphere is it considered 'space'?
2) I see a lot of responses about seeing the ISS via telescope from "there's no possible way to know what it is" to "it's a hologram". I have to ask, have any FE believers grabbed their telescope and looked up through it to check out the ISS? Why is it difficult to believe ones own eyes? How do you think they put a hologram in everyone's telescope (including a home-made one if some hard-core backyard astronomer made one him/herself)
3) Why do FE believers accept a 'blue earth'? I see this argument a lot, saying Earth is special because it is blue. But wouldn't you need to travel outside of earth to verify that it is, indeed, blue?
4) Live feeds of astronaut re-entry, personal videos on phones, and first-person accounts of such events. This would be very hard to fake if indeed, if the conspiracy theory holds. Can I get an explanation from a FE believer on such events? How did they 'make it look like' a re-entry pod came from the ISS for re-entry?
5) what about 'space junk' that has fallen back to earth? Conspiracy? Well-made props?

Trying to get some good answers please. Please don't answer back with "How do you know it is/isn't, it isn't known" etc. I would like legit answers with thought put behind them. I don't want this to become an argue-fest contradicting theory, but I would like them to be thought-out answers. "it just is" is not a well thought out answer.

Thanks everyone, lets keep this a clean, educated discussion.
Title: Re: Space Flight
Post by: MuNotEpsilonNot on May 26, 2013, 11:42:43 PM
well....

1) "There is no firm boundary where space begins. However the Kármán line, at an altitude of 100 km (62 mi) above sea level,[3] is conventionally used as the start of outer space in space treaties and for aerospace records keeping" - Type in Kármán line in Google for multiple sources

2) If I show you a picture, there'll be "it's photoshopped" ringing throughout the corners, and thus we have met in full circle. This is why I have asked if ANY FE believers have actually looked through a telescope with their own eyes to see it for themselves...

3) If you look up at the sky at night, it's black. Ocean is not blue, water is not blue, but it is reflecting the sky. Thus at night again, it's black. So, why is Earth not theorized black since our sky is black half of the time?

4)"Can you show me a realistic re-entry"
I don't know how much more real you want it other than live feeds and first person viewing which is why I said these specifically. I know that "Well if you saw it on TV, it must have been pre-recorded in Hollywood" would have been used as an answer if I did not specify.

5) Your reply to my number five is a logical fallacy, not an answer: See Argument from ignorance (I'm not calling you ignorant for the record, that's just the name they gave it): http://en.wikipedia.org/wiki/Argument_from_ignorance (http://en.wikipedia.org/wiki/Argument_from_ignorance)
And not only do I refer to seeing it fall or getting impaled with space junk, but the manner in which it falls. Take for example a bullet at a crime scene. Later, police find a gun on a suspect. They fire a bullet from that gun. Forensic scientists study the bullets and see the same patters from coming out of the barrel. Thus, the mystery bullet from the scene came from the suspect's gun. Similarly, various ways space junk enters similar to a meteor could be used to prove that the space junk actually came from space.

Again, not looking for (here I go using this term again) logical fallacies. This just sends us in a circle and gets us no where.

Title: Re: Space Flight
Post by: icanbeanything on May 27, 2013, 01:23:52 PM
Space doesn't start anywhere in that sense. There is no clear line where air just stops being there and space begins. The air just gets thinner and thinner, until, very far away from Earth, there's basically no air in any practical purpose.
Title: Re: Space Flight
Post by: MuNotEpsilonNot on May 27, 2013, 02:42:05 PM
Well, for your reply to number one, I suppose that makes everything else a moot point doesn't it? From reading the wiki, i've deduced that is 98% of FET. And since it doesn't count, I guess the conversation is over. Can't argue against something that doesn't count right? Guess I should probably stop working on my Ph.D in physics if that's the case too... unproven theories in science rely heavily on things like that, things that are not fully proven, speculation or cannot going to the be proven. Guess I should start going to the gym so I can make good money add a stopper since the world doesn't make sense anymore lol.
Thanks for replying to my questions by the way, seriously thanks. You were the only one who really answered anything.
Good talk.
Title: Re: Space Flight
Post by: hoppy on May 27, 2013, 02:47:07 PM
Space doesn't start anywhere in that sense. There is no clear line where air just stops being there and space begins. The air just gets thinner and thinner, until, very far away from Earth, there's basically no air in any practical purpose.
Nasa gives astronaut wings for going 62 miles up, used to be 50 miles

To earn an astronaut badge, a military officer must complete all required training and participate in a space flight more than 100 kilometers (62 miles) above the Earth. This boundary, known as the Kármán line, comes from the Fédération Aéronautique Internationale. However, in the 1960s, the United States Department of Defense awarded astronaut badges to military and civilian pilots who flew aircraft higher than 50 miles (80 kilometers).[1] Seven USAF and NASA pilots qualified for the astronaut badge by flying the sub-orbital X-15 rocket spaceplane.

http://en.wikipedia.org/wiki/Astronaut_wings (http://en.wikipedia.org/wiki/Astronaut_wings)
Title: Re: Space Flight
Post by: MuNotEpsilonNot on May 27, 2013, 07:38:12 PM
Well, for your reply to number one, I suppose that makes everything else a moot point doesn't it? From reading the wiki, i've deduced that is 98% of FET. And since it doesn't count, I guess the conversation is over. Can't argue against something that doesn't count right? Guess I should probably stop working on my Ph.D in physics if that's the case too... unproven theories in science rely heavily on things like that, things that are not fully proven, speculation or cannot going to the be proven. Guess I should start going to the gym so I can make good money add a stopper since the world doesn't make sense anymore lol.
Thanks for replying to my questions by the way, seriously thanks. You were the only one who really answered anything.
Good talk.

Clearly by "add a stopper" I meant "as a stripper". Silly phone
Title: Re: Space Flight
Post by: icanbeanything on May 28, 2013, 01:00:03 AM
Space doesn't start anywhere in that sense. There is no clear line where air just stops being there and space begins. The air just gets thinner and thinner, until, very far away from Earth, there's basically no air in any practical purpose.
Nasa gives astronaut wings for going 62 miles up, used to be 50 miles

To earn an astronaut badge, a military officer must complete all required training and participate in a space flight more than 100 kilometers (62 miles) above the Earth. This boundary, known as the Kármán line, comes from the Fédération Aéronautique Internationale. However, in the 1960s, the United States Department of Defense awarded astronaut badges to military and civilian pilots who flew aircraft higher than 50 miles (80 kilometers).[1] Seven USAF and NASA pilots qualified for the astronaut badge by flying the sub-orbital X-15 rocket spaceplane.

http://en.wikipedia.org/wiki/Astronaut_wings (http://en.wikipedia.org/wiki/Astronaut_wings)

The Kármán line is an entirely arbitrary line, decided upon by humans, as you said, the FAI. Of course, such a spiritual delimiter is needed for bureaucracy purposes.

But understand that in the real world, there is nothing special about the Kármán line. Nothing physically happens there. There's just rarefied air below it, and more of the same rarefied air above it. If you were floating right on the Kármán line, it wouldn't feel any different from being slightly under or above it (hint: it would feel like dying).
Title: Re: Space Flight
Post by: Scintific Method on May 28, 2013, 02:39:10 AM
I heard (or read, can't remember which now) somewhere that the Kármán line is the average altitude at which an aircraft's wing is no longer able to generate sufficient lift at any speed lower than orbital speed (to put that another way, you might as well not have wings at this point, because you'll continue to orbit without them).

I know that'll attract some derisive comments from the flatties! Go for it guys, doesn't change the fact it's how the line is defined.
Title: Re: Space Flight
Post by: icanbeanything on May 28, 2013, 03:34:20 AM
I heard (or read, can't remember which now) somewhere that the Kármán line is the average altitude at which an aircraft's wing is no longer able to generate sufficient lift at any speed lower than orbital speed (to put that another way, you might as well not have wings at this point, because you'll continue to orbit without them).

I know that'll attract some derisive comments from the flatties! Go for it guys, doesn't change the fact it's how the line is defined.
How would you continue to orbit? surely you would have to be doing a far far greater speed than the fake ISS in order for this to happen, going by the bull crap we are treated to I mean.

He means that an aircraft would need to have at least orbital speed for its wings to generate lift. Orbital speed by definition is the speed at which, at a given altitude, you are in orbit. Yes, at that altitude it would be way faster than the ISS is going, and it would be basically impossible (and pointless) to achieve. It was not a practical suggestion, just a thought experiment. He said that above a certain height there is no more point for wings, because they don't work without speeds greater than the orbital speed, and if you do have orbital speed, you don't need wings anymore.

The point was just to illustrate why aircraft don't work above a certain height.
Title: Re: Space Flight
Post by: iwanttobelieve on June 02, 2013, 04:58:46 AM
anyone with a cheap telescope can tell that space flight is possible.
instead of posting 50 times a day, scepti, maybe you can buy one, and perform Zetetic experiments,
and report back to us.
Remember, this is a Zetetic forum and not a conspiracy theorists one.
Title: Re: Space Flight
Post by: iwanttobelieve on June 02, 2013, 09:34:32 AM
"Please list the number of experiments you have performed to determine that this is actually, "bull crap".
I myself have performed many, its called the Zetetic Method.
Or have you been force fed into believing only what the FAQ tells you?
Title: Re: Space Flight
Post by: icanbeanything on June 02, 2013, 01:40:50 PM
According to you people, anyone with partial sight can tell that space flight is possible, because all that comes out of you lot are fabrications and a belief that something is up there, so it must be in space or a space station or satellite.
Once you lose the atmosphere, you lose the rocket.
Understand this and you are half way there to figuring out the bull crap you have been saturated with.

I don't understand... Are you saying you believe rockets don't work when not in the atmosphere? By the way, they do. Nothing about the mechanics of a rocket demands an atmosphere. In fact, they work a lot better outside the atmosphere, since the atmosphere tends to, you know, cause aerodynamic drag.
Title: Re: Space Flight
Post by: Rama Set on June 02, 2013, 04:29:15 PM
According to you people, anyone with partial sight can tell that space flight is possible, because all that comes out of you lot are fabrications and a belief that something is up there, so it must be in space or a space station or satellite.
Once you lose the atmosphere, you lose the rocket.
Understand this and you are half way there to figuring out the bull crap you have been saturated with.

I don't understand... Are you saying you believe rockets don't work when not in the atmosphere? By the way, they do. Nothing about the mechanics of a rocket demands an atmosphere. In fact, they work a lot better outside the atmosphere, since the atmosphere tends to, you know, cause aerodynamic drag.
Not a chance can a rocket work in space, I'm sorry but it's 100% true.
You have been duped, sadly.

I just wanted to pop in and say what an incredible ignorant idiot you are sceptimatic. Return to your previous state of fool's paradise now.
Title: Re: Space Flight
Post by: Scintific Method on June 02, 2013, 06:29:43 PM
Not a chance can a rocket work in space...

Tell us, in your own words, exactly why a rocket cannot work in space.

Also...

What experiment have you performed that shows space flight is possible?

...tell us what experiments you have done to show it's not.

Please note: "I just know", or any variation thereof, will not be considered as an acceptable answer.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 02:02:24 AM
Not a chance can a rocket work in space, I'm sorry but it's 100% true.
You have been duped, sadly.

You claim it's 100% true, but can you give at least a reason why you believe that?

I don't mean "Have there been space flights?", that is another topic, the question is "Why wouldn't a rocket work in a vacuum?".
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 02:11:31 AM
Not a chance can a rocket work in space, I'm sorry but it's 100% true.
You have been duped, sadly.

You claim it's 100% true, but can you give at least a reason why you believe that?

I don't mean "Have there been space flights?", that is another topic, the question is "Why wouldn't a rocket work in a vacuum?".
Simple answer is, there is nothing for the fuel to push against.

The fuel is pushing against the rocket, not the air. That's how rockets work. Fuel comes out one end, so it is pushing the rocket the opposite way. The presence of air only works against the rocket, slowing it down (it is pushing from the opposite side, the front of the rocket).
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 02:27:19 AM
With all due respect to you. This is what they would have you believe but if you search your mind, you will know that this is absolute nonsense.

If the fuel comes out in a vacuum, it's doing no work. It's simply expanded into that vacuum.

Let me try to explain what my mind is telling me:

Yes, the gas resulting from the burning of the fuel would be released into the vacuum. But as it expands in all directions, it is also expanding in the direction of the rocket. The gas itself from the fuel is NOT vacuum, it is a pretty dense gas, full of fast particles. It is this gas that does the pushing, in all directions, including the direction where there's a rocket in the way.

Think of it like this: If you were in a vacuum, and a hand grenade exploded right next to you, would it not affect you? Air or no air, the stuff coming out of the grenade would expand in every direction, including the one you're in, and it would certainly hurt you. This is what basically happens in a rocket too.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 02:42:11 AM
With all due respect to you. This is what they would have you believe but if you search your mind, you will know that this is absolute nonsense.

If the fuel comes out in a vacuum, it's doing no work. It's simply expanded into that vacuum.

Let me try to explain what my mind is telling me:

Yes, the gas resulting from the burning of the fuel would be released into the vacuum. But as it expands in all directions, it is also expanding in the direction of the rocket. The gas itself from the fuel is NOT vacuum, it is a pretty dense gas, full of fast particles. It is this gas that does the pushing, in all directions, including the direction where there's a rocket in the way.

Think of it like this: If you were in a vacuum, and a hand grenade exploded right next to you, would it not affect you? Air or no air, the stuff coming out of the grenade would expand in every direction, including the one you're in, and it would certainly hurt you. This is what basically happens in a rocket too.
The grenade is a sealed unit. The rocket is not.

It is sealed up to the point when it explodes. The rocket is not sealed before because you don't want it to perform like a grenade (explode). It allows the gas to escape one way, thus pushing the rocket the other way. If you put a hole in a grenade, you could theoretically make a rather poor rocket out of it.
Title: Re: Space Flight
Post by: Scintific Method on June 03, 2013, 02:50:42 AM
Not a chance can a rocket work in space...

Tell us, in your own words, exactly why a rocket cannot work in space.

Also...

What experiment have you performed that shows space flight is possible?

...tell us what experiments you have done to show it's not.

Please note: "I just know", or any variation thereof, will not be considered as an acceptable answer.
I've already been through all of this but in a nutshell, a rocket cannot and will not and never will, work in a vacuum, which we are told space is.

I'm well aware that Newtons laws will immediately get brought in here and that the old medicine ball and chair trick or ice skates and ball trick will get used but it's false and a con and does not represent space if it is the vacuum we are told it is.

Rockets do not work in a vacuum in terms of propulsion. It's impossible.

Sorry scepti, but my shoulder agrees with Newton every time I fire a shotgun; his third law of motion ("for every action there is an equal and opposite reaction"), which is what rockets work on, definitely holds true. There is nowhere near enough pressure pushing on the atmosphere to generate the amount of recoil felt when firing a buckshot load, it can only be the reaction to accelerating the mass of lead down the barrel. Come to think of it, if all you had in space was a shotgun, you could propel yourself along quite well! (Silly I know, but it would be kind of fun!)
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 02:50:51 AM
With all due respect to you. This is what they would have you believe but if you search your mind, you will know that this is absolute nonsense.

If the fuel comes out in a vacuum, it's doing no work. It's simply expanded into that vacuum.

Let me try to explain what my mind is telling me:

Yes, the gas resulting from the burning of the fuel would be released into the vacuum. But as it expands in all directions, it is also expanding in the direction of the rocket. The gas itself from the fuel is NOT vacuum, it is a pretty dense gas, full of fast particles. It is this gas that does the pushing, in all directions, including the direction where there's a rocket in the way.

Think of it like this: If you were in a vacuum, and a hand grenade exploded right next to you, would it not affect you? Air or no air, the stuff coming out of the grenade would expand in every direction, including the one you're in, and it would certainly hurt you. This is what basically happens in a rocket too.
The grenade is a sealed unit. The rocket is not.

It is sealed up to the point when it explodes. The rocket is not sealed before because you don't want it to perform like a grenade (explode). It allows the gas to escape one way, thus pushing the rocket the other way. If you put a hole in a grenade, you could theoretically make a rather poor rocket out of it.
If you put a hole in the grenade, you then render it useless as it's explosive would be basically a burn and expanded "immediately" into the vacuum.

Yes, but it would push the grenade the other way, just like a rocket. Think of it this way: when there's no hole in the grenade, the explosive just makes its own holes in it, and this is what makes the grenade explode. It's the same thing, but one is controlled, creating a rocket, and the other is uncontrolled, creating a bomb. You can just as well make a bomb out of a rocket by sealing the exit.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 03:00:44 AM
When rockets fire lead shot or ball bearings or even bowling balls from an enclosed chamber, then we can discuss that.
For now, we need to concentrate on rockets "burning" fuel.

And why do you think there's a difference? The burning of the fuel produces gas, this gas has mass just as a lead shot has mass. This is what causes the effect, it doesn't matter if its a single ball or lots and lots of little balls that make up a gas.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 03:07:12 AM
When rockets fire lead shot or ball bearings or even bowling balls from an enclosed chamber, then we can discuss that.
For now, we need to concentrate on rockets "burning" fuel.

And why do you think there's a difference? The burning of the fuel produces gas, this gas has mass just as a lead shot has mass. This is what causes the effect, it doesn't matter if its a single ball or lots and lots of little balls that make up a gas.
It doesn't matter how much mass it has. The vacuum will willingly accept it all and beg for more, because it's a fast eater, as in milliseconds to render your rocket empty.

Your rocket doesn't empty that fast because it has a huge fuel tank that is constantly feeding it, creating more gas. The vacuum can only "eat" it just as fast as it is produced. Why is it different from firing a gun in space? The vacuum will just as willingly accept your bullet, so why would the bullet give you propulsion and the gas not?

Really, this is again one of those things that can be very easily tested with a tiny model rocket and a vacuum chamber.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 03:09:46 AM
Here's a vacuum chamber test of a rocket engine. Notice how the exhaust doesn't behave in any way differently. If you're wondering where the sound is coming from, since it doesn't travel in a vacuum: it does travel through the engine and the scaffold holding the engine. It's also why it is so high-pitched, because the speed of sound is much greater in metal.

SpaceX Testing - Draco Thruster Vacuum Firing (http://#ws)
Title: Re: Space Flight
Post by: Scintific Method on June 03, 2013, 03:25:46 AM
When rockets fire lead shot or ball bearings or even bowling balls from an enclosed chamber, then we can discuss that.
For now, we need to concentrate on rockets "burning" fuel.

Don't you get it? It doesn't matter what is being accelerated, it's a case of how much and how fast.

Rockets expel a far greater mass of gas than a shotgun does of shot, and they expel it at far greater speed too. To achieve that speed, the gas has to be accelerated, which happens inside the rocket (just like the shot is accelerated inside the shotgun). The gas is accelerated toward the exhaust, as that is it's only means of escape, so the rocket is accelerated by a proportional amount in the opposite direction.

Yes, the gas expands rapidly into the vacuum, but it has already done it's work, so that expansion is irrelevant.

If it's a question of retaining the fuel so that it can burn, then all you need to realise is that it takes time for the burnt gasses to expand out of the way, in the meantime they act like a plug, allowing the remaining fuel to burn at a steady rate. When the rocket is not required, internal valves shut off the flow of fuel.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 03:25:54 AM
If rockets do this, then rockets work in space and I'm wrong.
Do they do this?

Yes, the plate would fly away in opposite direction of the rocket. The rest of the fuel would also expand into space, but this expansion would also push the rocket, too. I don't see why you don't understand that it does.

For instance, blank shots fired from a gun (no bullet, just the propellant) also create recoil. There's no bullet leaving the chamber, only the expanding gas from the ignition of the propellant. The recoil is generated just as it would in a rocket.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 03:38:57 AM
When rockets fire lead shot or ball bearings or even bowling balls from an enclosed chamber, then we can discuss that.
For now, we need to concentrate on rockets "burning" fuel.

Don't you get it? It doesn't matter what is being accelerated, it's a case of how much and how fast.

Rockets expel a far greater mass of gas than a shotgun does of shot, and they expel it at far greater speed too. To achieve that speed, the gas has to be accelerated, which happens inside the rocket (just like the shot is accelerated inside the shotgun). The gas is accelerated toward the exhaust, as that is it's only means of escape, so the rocket is accelerated by a proportional amount in the opposite direction.

Yes, the gas expands rapidly into the vacuum, but it has already done it's work, so that expansion is irrelevant.

If it's a question of retaining the fuel so that it can burn, then all you need to realise is that it takes time for the burnt gasses to expand out of the way, in the meantime they act like a plug, allowing the remaining fuel to burn at a steady rate. When the rocket is not required, internal valves shut off the flow of fuel.
On earth, the work is done when it pushes against the atmosphere, "expanding" into it and the atmosphere pushes right back.

That is not how a rocket works. It's not the pushing against air that does it. That effect does nothing, since the same atmosphere is pushing on the front of the rocket. The work is done by the expanding gas pushing on the rocket itself, otherwise the rocket wouldn't move at all, there would be a tug of war of equal force between the air behind and in front of the rocket, that wouldn't do a thing.

Quote
Blank shots are still powder charges inside a "sealed" chamber.

The chamber is "sealed" until the gunpowder is ignited. When this happens, the pressure inside creates a rupture on the seal at the front (since this is deliberately made weaker), thus there now is an exit for the expanding gas. It is exactly like a rocket engine, only with a very short fuel reserve. That's what gives you the recoil.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 03:47:56 AM
It's the rockets hot gases "expanding" the air and the surrounding air rushing into to replace it.
Rockets do not work like bullets.

The air is not rushing in to replace it. No air goes inside while the rocket is firing. The pressure of the gas inside is greater than outside air pressure.

If the air from the back of the rocket rushed into the rocket's chamber, that would mean there was smaller pressure inside the chamber, this would also pull the rocket back, not push it forward!

The pressure inside is greater, gas is going out, nothing is going in (except the fuel from the tanks, but that's from inside the rocket).
Title: Re: Space Flight
Post by: Scintific Method on June 03, 2013, 03:51:19 AM
When rockets fire lead shot or ball bearings or even bowling balls from an enclosed chamber, then we can discuss that.
For now, we need to concentrate on rockets "burning" fuel.

Don't you get it? It doesn't matter what is being accelerated, it's a case of how much and how fast.

Rockets expel a far greater mass of gas than a shotgun does of shot, and they expel it at far greater speed too. To achieve that speed, the gas has to be accelerated, which happens inside the rocket (just like the shot is accelerated inside the shotgun). The gas is accelerated toward the exhaust, as that is it's only means of escape, so the rocket is accelerated by a proportional amount in the opposite direction.

Yes, the gas expands rapidly into the vacuum, but it has already done it's work, so that expansion is irrelevant.

If it's a question of retaining the fuel so that it can burn, then all you need to realise is that it takes time for the burnt gasses to expand out of the way, in the meantime they act like a plug, allowing the remaining fuel to burn at a steady rate. When the rocket is not required, internal valves shut off the flow of fuel.
Oh, I get it. No offence to you but you do not get it.

The fuel in your rocket does no work at all until it is expelled from the rockets rear end. On earth, the work is done when it pushes against the atmosphere, "expanding" into it and the atmosphere pushes right back.
In space, you can have a billion ton rocket and it's fuel will expand into space, doing no work, because space will just accept it and beg for more.
The rocket in a vacuum is useless.

Ok, you don't get it. Let me try putting this another way:

Yes, the burning fuel expands into space. Rapidly. But space is only available in one direction: the exhaust. In all other directions, there is the rocket's nozzle. Here's a nice simple diagram of a combustion chamber and nozzle:

(http://upload.wikimedia.org/wikipedia/commons/thumb/5/55/Rocket_thrust.svg/500px-Rocket_thrust.svg.png)

The arrow pointing right represents the escaping gas, the little arrows all around represent the pressure exerted by the gas on the inside of the combustion chamber and nozzle, and the arrow pointing left represents the net resultant force pushing the rocket along.

Actually, I have a question for any actual rocket scientists on here: given that rockets work on a pressure differential, wouldn't that make them more effective in a vacuum?
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 04:00:21 AM
It's the rockets hot gases "expanding" the air and the surrounding air rushing into to replace it.
Rockets do not work like bullets.

The air is not rushing in to replace it. No air goes inside while the rocket is firing. The pressure of the gas inside is greater than outside air pressure.

If the air from the back of the rocket rushed into the rocket's chamber, that would mean there was smaller pressure inside the chamber, this would also pull the rocket back, not push it forward!

The pressure inside is greater, gas is going out, nothing is going in (except the fuel from the tanks, but that's from inside the rocket).
You've misunderstood what I said.
I meant the rockets gases expanding the air and the air,"under" that expanding air, rushes up and in to fill the void, action/reaction.


I hope I understood well what you said, but what I said in response was that at no point is any void created for air to fill.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 04:08:54 AM
It's the rockets hot gases "expanding" the air and the surrounding air rushing into to replace it.
Rockets do not work like bullets.

The air is not rushing in to replace it. No air goes inside while the rocket is firing. The pressure of the gas inside is greater than outside air pressure.

If the air from the back of the rocket rushed into the rocket's chamber, that would mean there was smaller pressure inside the chamber, this would also pull the rocket back, not push it forward!

The pressure inside is greater, gas is going out, nothing is going in (except the fuel from the tanks, but that's from inside the rocket).
You've misunderstood what I said.
I meant the rockets gases expanding the air and the air,"under" that expanding air, rushes up and in to fill the void, action/reaction.


I hope I understood well what you said, but what I said in response was that at no point is any void created for air to fill.
When you go swimming and you are doing the breast stroke, what are you doing?
You are acting pushing the water behind you against a barrier of water that's already filled the part where your body is moving in and it propels you forward.
It's a crude way of explaining why rockets work in an atmosphere.

Try and do the breast stroke in an empty pool.

Like I said for the fifth time, that's not how rockets work. If you really want a comparison with water, this is how rockets work:

Water Jet Pack: Get High with Jetlev! (http://#ws)

This is basically a rocket with water as a propellant. You can see it has nothing to do with water filling any void.

And please, don't say this is fake too.
Title: Re: Space Flight
Post by: Scintific Method on June 03, 2013, 04:18:40 AM
When you go swimming and you are doing the breast stroke, what are you doing?
You are acting pushing the water behind you against a barrier of water that's already filled the part where your body is moving in and it propels you forward.
It's a crude way of explaining why rockets work in an atmosphere.

Try and do the breast stroke in an empty pool.
This does not explain how a rocket works. A propeller driven airplane, yes, but a rocket? No.

Rockets work by accelerating gas (which they create by burning the fuel they carry in their own on-board tanks) out of an exhaust nozzle. It doesn't need anything outside to push against, it does all it's work just by accelerating the gas in the direction the exhaust nozzle is pointing. You don't even need to burn the fuel, you could just let it escape under it's own pressure, and it would still generate thrust.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 04:24:41 AM
When you go swimming and you are doing the breast stroke, what are you doing?
You are acting pushing the water behind you against a barrier of water that's already filled the part where your body is moving in and it propels you forward.
It's a crude way of explaining why rockets work in an atmosphere.

Try and do the breast stroke in an empty pool.
This does not explain how a rocket works. A propeller driven airplane, yes, but a rocket? No.

Rockets work by accelerating gas (which they create by burning the fuel they carry in their own on-board tanks) out of an exhaust nozzle. It doesn't need anything outside to push against, it does all it's work just by accelerating the gas in the direction the exhaust nozzle is pointing. You don't even need to burn the fuel, you could just let it escape under it's own pressure, and it would still generate thrust.

Of course there is no need for fuel specifically, it's just used since it can create a huge amount of gas when burned.

Another simple example of a rocket would be when you release a balloon without tying its mouth. The air inside is of much greater pressure, thus it is forced out through the mouth, and pushes on the balloon as it escapes. No air from outside enters the balloon until it settles.
Title: Re: Space Flight
Post by: Scintific Method on June 03, 2013, 04:28:11 AM
Another simple example of a rocket would be when you release a balloon without tying its mouth. The air inside is of much greater pressure, thus it is forced out through the mouth, and pushes on the balloon as it escapes. No air from outside enters the balloon until it settles.

A simple and fun demonstration of rocket physics, thanks again ican! Oh, and this will work in a vacuum too, provided the balloon is strong enough not to pop first.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 04:35:53 AM
Another simple example of a rocket would be when you release a balloon without tying its mouth. The air inside is of much greater pressure, thus it is forced out through the mouth, and pushes on the balloon as it escapes. No air from outside enters the balloon until it settles.

A simple and fun demonstration of rocket physics, thanks again ican! Oh, and this will work in a vacuum too, provided the balloon is strong enough not to pop first.

Yeah, it will work just the same. You fill the balloon with 1atm less pressure, and it will expand to the same size in the vacuum as it would with that 1atm extra pressure in air, it will not pop.

You can't fill a balloon with your breath in a vacuum, though :P
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 04:43:51 AM
Seriously, do you think this is a good analogy for your vacuum rocket.
Describe what the long pipe is doing and then you might realise.

It is a very good analogy for a rocket, vacuum or no vacuum. The long pipe is for the pump to draw water from the sea. The sea acts as the fuel tank for this "rocket", allowing the rider to not have to carry all that water with him. The pump is to make the water exiting the jet be of higher pressure, since that is what generates lift. It is exactly a rocket.

You can make a water rocket yourself, I'm sure you've heard of it too. Take a water bottle, put about 1/3 water in it, attach its end to a bike pump and position it with its mouth downward, then start pumping. At some point the pressure inside will be great enough that the bottle will separate from the pump, and from there on it's a rocket. It's the same thing that's happening in this rig too, but the pump here is much stronger and it's getting a constant stream of water from the sea, so it doesn't "run out".
Title: Re: Space Flight
Post by: Scintific Method on June 03, 2013, 04:45:09 AM
When you go swimming and you are doing the breast stroke, what are you doing?
You are acting pushing the water behind you against a barrier of water that's already filled the part where your body is moving in and it propels you forward.
It's a crude way of explaining why rockets work in an atmosphere.

Try and do the breast stroke in an empty pool.
This does not explain how a rocket works. A propeller driven airplane, yes, but a rocket? No.

Rockets work by accelerating gas (which they create by burning the fuel they carry in their own on-board tanks) out of an exhaust nozzle. It doesn't need anything outside to push against, it does all it's work just by accelerating the gas in the direction the exhaust nozzle is pointing. You don't even need to burn the fuel, you could just let it escape under it's own pressure, and it would still generate thrust.
So why do  rockets burn fuel on lift off then, on earth?

Releasing pressurised gas only gives you so much thrust, it's good for fine maneuvering or really small payloads, but not for big rockets. Rockets (the kind we're talking about for space travel) are big, you need more gas to move one of them, and the easiest way to generate large amounts of gas is to burn liquid (or solid) rocket fuel.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 04:49:01 AM
So why do  rockets burn fuel on lift off then, on earth?

They burn fuel to generate gas. This gas is what causes the propulsion due to its great pressure. Think again of that water jet: it needs to be connected to the sea to work, it needs water. It would be very inefficient for it to carry its own water around. A water rocket would have to carry its own water with it, and also create the pressure with a pump, all this takes a lot of energy and doesn't give you enough thrust to lift itself.

Well, fuel stores energy very efficiently, so burning it gives you much more gas at your disposal, so it makes it efficient to carry your fuel around. Your pump no longer has to create the exhaust pressure, it only needs to add fuel to the chamber, the burning itself is what creates pressure.

Quote
How will it work in a vacuum?

The same way it would in air, it would shoot off in one direction while shrinking as it loses its air. Just that it wouldn't come to a stop once it gains speed, since there would be no air resistance to slow it.
Title: Re: Space Flight
Post by: Rama Set on June 03, 2013, 04:51:53 AM
Seriously, do you think this is a good analogy for your vacuum rocket.
Describe what the long pipe is doing and then you might realise.

It is a very good analogy for a rocket, vacuum or no vacuum. The long pipe is for the pump to draw water from the sea. The sea acts as the fuel tank for this "rocket", allowing the rider to not have to carry all that water with him. The pump is to make the water exiting the jet be of higher pressure, since that is what generates lift. It is exactly a rocket.

You can make a water rocket yourself, I'm sure you've heard of it too. Take a water bottle, put about 1/3 water in it, attach its end to a bike pump and position it with its mouth downward, then start pumping. At some point the pressure inside will be great enough that the bottle will separate from the pump, and from there on it's a rocket. It's the same thing that's happening in this rig too, but the pump here is much stronger and it's getting a constant stream of water from the sea, so it doesn't "run out".
As long as the air pressure is stronger than the thing it's up against, ie, the man, then it will lift him or anything else up...but it must exhaust that pressure against something. In this case it's the air under him and the dense water.
In space, you do not have any of this, so your are rendered a dud.

You are wrong. You should learn more.
Title: Re: Space Flight
Post by: Rama Set on June 03, 2013, 05:12:19 AM
Seriously, do you think this is a good analogy for your vacuum rocket.
Describe what the long pipe is doing and then you might realise.

It is a very good analogy for a rocket, vacuum or no vacuum. The long pipe is for the pump to draw water from the sea. The sea acts as the fuel tank for this "rocket", allowing the rider to not have to carry all that water with him. The pump is to make the water exiting the jet be of higher pressure, since that is what generates lift. It is exactly a rocket.

You can make a water rocket yourself, I'm sure you've heard of it too. Take a water bottle, put about 1/3 water in it, attach its end to a bike pump and position it with its mouth downward, then start pumping. At some point the pressure inside will be great enough that the bottle will separate from the pump, and from there on it's a rocket. It's the same thing that's happening in this rig too, but the pump here is much stronger and it's getting a constant stream of water from the sea, so it doesn't "run out".
As long as the air pressure is stronger than the thing it's up against, ie, the man, then it will lift him or anything else up...but it must exhaust that pressure against something. In this case it's the air under him and the dense water.
In space, you do not have any of this, so your are rendered a dud.

You are wrong. You should learn more.
You see that long pipe attached to the man that's feeding his rocket. It's not just feeding it with water , it's feeding him with immense water pressure too.

I am correct, you should learn more and stop being took in by the lies.
Rockets do not work in space as the vacuum we are told and never have done.

If you think the exhaust of a rocket gets significant thrust by pushing on air, then you are ignorant. On your view jet propulsion should be more effective in water than air, since it is easier to push on water then air. The reality is that jet propulsion works better in air than water.
Title: Re: Space Flight
Post by: Rama Set on June 03, 2013, 05:24:30 AM
I am not twisting anything. I am talking about the basics of jet propulsion. Jet propulsion does not generate thrust by pushing off of anything. Jet propulsion efficiency goes up in less viscous fluids. The facts given in my previous post illustrate this.
Title: Re: Space Flight
Post by: Scintific Method on June 03, 2013, 05:26:52 AM
Thrust against what?

Well, technically against the rocket itself.

To put this a way you might understand, think of what would happen if you placed an object next to a bomb when it went off. The expanding gas from the explosion would push that object away from the bomb, really fast! That's what's happening with a rocket, except with greater control of the burn: as the gas expands, it tried to expand in all directions. Thing is, there's a rocket in the way on one side, so that rocket gets pushed away. On the other side it's just a vacuum, so the gas expands freely in that direction.

It's a clumsy explanation, but I thought you might have a bit more luck getting your head around it.
Title: Re: Space Flight
Post by: Rama Set on June 03, 2013, 05:31:13 AM
I am not twisting anything. I am talking about the basics of jet propulsion. Jet propulsion does not generate thrust by pushing off of anything. Jet propulsion efficiency goes up in less viscous fluids. The facts given in my previous post illustrate this.
If a person gets thrown up on a water jet, vertically, what is keeping that person in the air?

Exactly. The jet pushes the rocket up.
Title: Re: Space Flight
Post by: Rama Set on June 03, 2013, 05:34:59 AM
Thrust against what?

Well, technically against the rocket itself.

To put this a way you might understand, think of what would happen if you placed an object next to a bomb when it went off. The expanding gas from the explosion would push that object away from the bomb, really fast! That's what's happening with a rocket, except with greater control of the burn: as the gas expands, it tried to expand in all directions. Thing is, there's a rocket in the way on one side, so that rocket gets pushed away. On the other side it's just a vacuum, so the gas expands freely in that direction.

It's a clumsy explanation, but I thought you might have a bit more luck getting your head around it.
Trust me I have my head wrapped around it all very well, only my stance is different from yours, so what we are going to have to do is melt each others brains until one of us accepts one explanation that cannot be refuted.

Buckle up because this isn't going to be a walk in the park by any stretch of the imagination.
A rocket is not a bomb. It burns fuel at a furious rate, that's all.

Actually a rocket is a bomb detonated in extremely controlled and precise circumstances. The challenger shuttle is an example of what happens when those circumstances become less controlled.
Title: Re: Space Flight
Post by: Rama Set on June 03, 2013, 05:37:04 AM
I am not twisting anything. I am talking about the basics of jet propulsion. Jet propulsion does not generate thrust by pushing off of anything. Jet propulsion efficiency goes up in less viscous fluids. The facts given in my previous post illustrate this.
If a person gets thrown up on a water jet, vertically, what is keeping that person in the air?

Exactly. The jet pushes the rocket up.
Now what is acting on that jet of water to keep that person up?

If you are referring to something like a geyser, the geothermal energy ultimately pushes the water and the pressure comes from a combination of that energy and the area of the hole the geyser shoots through.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 05:40:26 AM
Nobody is being lied to, Scepti. You just have a wrong understanding of the concept, we're not lying to you either. These are not things we just read in a book, and they aren't things we just came up with on a whim. These are things that make sense.
Title: Re: Space Flight
Post by: Scintific Method on June 03, 2013, 05:41:43 AM
Thrust against what?

Well, technically against the rocket itself.

To put this a way you might understand, think of what would happen if you placed an object next to a bomb when it went off. The expanding gas from the explosion would push that object away from the bomb, really fast! That's what's happening with a rocket, except with greater control of the burn: as the gas expands, it tried to expand in all directions. Thing is, there's a rocket in the way on one side, so that rocket gets pushed away. On the other side it's just a vacuum, so the gas expands freely in that direction.

It's a clumsy explanation, but I thought you might have a bit more luck getting your head around it.
Trust me I have my head wrapped around it all very well, only my stance is different from yours, so what we are going to have to do is melt each others brains until one of us accepts one explanation that cannot be refuted.

Buckle up because this isn't going to be a walk in the park by any stretch of the imagination.
A rocket is not a bomb. It burns fuel at a furious rate, that's all.

Plug the exhaust. Voila! Bomb.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 05:43:49 AM
I am not twisting anything. I am talking about the basics of jet propulsion. Jet propulsion does not generate thrust by pushing off of anything. Jet propulsion efficiency goes up in less viscous fluids. The facts given in my previous post illustrate this.
If a person gets thrown up on a water jet, vertically, what is keeping that person in the air?

Exactly. The jet pushes the rocket up.
Now what is acting on that jet of water to keep that person up?

The pressure of the water, created by the pumping mechanism, is keeping the person in the air. It has nothing to do with the air around the person. Honestly.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 06:20:14 AM
Nobody is being lied to, Scepti. You just have a wrong understanding of the concept, we're not lying to you either. These are not things we just read in a book, and they aren't things we just came up with on a whim. These are things that make sense.
You are being lied to about how rockets work, seriously. I can tell you right now, 1000,000% that they would not work in a vacuum.

Well, I can tell you the same way that they 100% work in vacuum, and I really don't know where you're getting the opposite idea. I've tried explaining why. And I'm not being lied to, I know this myself, I can work it out without someone needing to tell me.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 06:38:43 AM
Nobody is being lied to, Scepti. You just have a wrong understanding of the concept, we're not lying to you either. These are not things we just read in a book, and they aren't things we just came up with on a whim. These are things that make sense.
You are being lied to about how rockets work, seriously. I can tell you right now, 1000,000% that they would not work in a vacuum.

Well, I can tell you the same way that they 100% work in vacuum, and I really don't know where you're getting the opposite idea. I've tried explaining why. And I'm not being lied to, I know this myself, I can work it out without someone needing to tell me.
How you can possibly believe a rocket can work without an atmosphere is beyond me...but each to their own I suppose.

Well, like I said before, and tried explaining to you, I happen to know that the way a rocket's thrust works is independent of the medium it is placed in. The medium will only act to hinder the rocket's forward motion, and has no part in making the rocket work. Therefore, whether the rocket is in air, water, helium, soy sauce, honey, or a vacuum, it still works as a concept. That is what "independent" means.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 07:05:35 AM
A rocket cannot work in a vacuum because it's fuel would be expended immediately upon exhaust. It would simply expand into the vacuum, creating no propulsion whatsoever.

It would not expand "immediately" out into the vacuum. The gas inside would be leaving the rocket a bit faster than at normal atmospheric pressure, but the difference wouldn't be dramatic. You see, what's making the gas inside the rocket "leave" is not the outside medium, it's the inner pressure of the gas inside the rocket. Or more precisely, the pressure difference between inside and outside.

Since atmospheric pressure is basically nothing compared to the pressure of the exhaust of a liquid fuel rocket, it follows that the pressure difference when used in vacuum is barely greater than the pressure difference in air. So the exhaust gas would barely have a noticeable difference inside the rocket in a vacuum environment.

The exhaust gas leaves the rocket in quite a rush in both air and vacuum (no discernible difference), but it's certainly not an instant action. And the time it takes for the exhaust to leave is the time during which it's pushing on the rocket.

Seeing that a rocket engine can burn for quite some time, depending on fuel reserves, this time can hardly be called "instantly".
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 07:08:18 AM
I think the problem here is that you think vacuum is a magical and extremely complicated "state" that works differently from anything else you've heard of.

Vacuum is just a "state" in which gas is at zero pressure. This doesn't make it break the laws of physics. The difference between a vacuum and normal atmospheric pressure is only 15 psi. I'm sure you can think of plenty engineering applications which involve immense pressures compared to that. So why would a 15 psi pressure difference matter for a rocket?
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 07:33:18 AM
There are always fissures in vacuum chambers, and air is constantly getting in, which is why there is need for constant pumping.

Yet even with these fissures, the air outside doesn't "immediately" fill the chamber, since vacuum, as I said, isn't a magic "pop and it's gone" thing. It's just a pressure difference causing air outside to go in, but not at magical breakneck speeds to fill the chamber immediately. Even if you open a larger valve, air doesn't "immediately" fill the chamber, it takes quite a few seconds usually.

So there you go, gas doesn't instantly cease to exist when in a vacuum.

Consider the pressure differences again: vacuum to atmospheric pressure is only 15 psi. A car tyre already has twice that. And then imagine the pressure of the exhaust of a rocket. 15 psi makes almost no difference for it.
Title: Re: Space Flight
Post by: Rama Set on June 03, 2013, 07:39:46 AM
Nobody is being lied to, Scepti. You just have a wrong understanding of the concept, we're not lying to you either. These are not things we just read in a book, and they aren't things we just came up with on a whim. These are things that make sense.
You are being lied to about how rockets work, seriously. I can tell you right now, 1000,000% that they would not work in a vacuum.

You will excuse us if we do not take your opinion on science seriously.  You are lazy in research, ignorant of theory, and extremely biased against mainstream science.  Your 1,000,000% surety is worth... nothing.
Title: Re: Space Flight
Post by: Fizzy Logic on June 03, 2013, 07:42:11 AM
Http://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation (http://Http://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation) describes pretty well how a rocket works in vacuum.
Title: Re: Space Flight
Post by: Rama Set on June 03, 2013, 07:45:49 AM
Nobody is being lied to, Scepti. You just have a wrong understanding of the concept, we're not lying to you either. These are not things we just read in a book, and they aren't things we just came up with on a whim. These are things that make sense.
You are being lied to about how rockets work, seriously. I can tell you right now, 1000,000% that they would not work in a vacuum.

You will excuse us if we do not take your opinion on science seriously.  You are lazy in research, ignorant of theory, and extremely biased against mainstream science.  Your 1,000,000% surety is worth... nothing.
You take it however you feel, it's not important to me how "you" take it to be honest.

I know its not important to you, its not important to me that it is unimportant to you.  But you should also be aware that your opinion means nothing, because your responses are superficial.  If you put together substantial refutations, you would actually have some validity outside  of you and your mom's meatloaf dinner dates on Sunday.
Title: Re: Space Flight
Post by: Fizzy Logic on June 03, 2013, 07:49:19 AM
http://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation (http://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation) describes pretty well how a rocket works in vacuum.
Looking at sites like this will not enhance your prospects of ever finding the truth.

That is a law of physics whichnis proven. Why don't you take a trip to Cape Canaveral or Kourou or Baikonur... Or buy fireworks? Or build yourself your own rocket?
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 07:53:52 AM
The vacuum of space will not discriminate with whatever pressure is inside a rocket, it will be ready to accept it all, in any quantity and under and pressure.

No, the pressure difference is what matters. Greater pressure gas would exert a greater force on the walls of the rocket, and leave the rocket faster.

Also, the vacuum wouldn't necessarily pull apart a closed box filled with gas, as I think you believe. If the box can take the pressure of the gas within it without breaking, then the vacuum can just go screw himself, he's not getting any of that gas in the inside.

A small example: A car tire is usually inflated to about 30 psi, which is just about double of atmospheric pressure. The pressure difference between inside the tire and outside is 15 psi. This is pressure exerted on the inner walls of the tire, pushing on them, but the tire is built to withstand this pressure.

Now, inflate the tire to 15 psi and put in in a vacuum. The pressure difference is again 15 psi, just as much as it was before. So your tire would sit in that vacuum with no worries, holding that air inside in just about the same matter. It would not explode.

Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 09:12:09 AM
Anyway, I have no problems with this but  the release from a breach would be the same....no motion of the rocket. It would be a dud.

The release from the breach would be a jet of gas shooting out of the box/rocket, which would behave the same way as it does in air. My point with the pressure difference was basically that from the point of view of the rocket, the exhaust gas is of such high pressure that it makes no difference whether there's air or a vacuum around the rocket; since the difference in pressure is nearly the same, there's only a 15 psi difference, the atmosphere around the rocket is so thin compared to the rocket exhaust that it might as well be a vacuum. Just like for us humans, the pressure up 120,000 feet high, while not zero, might as well not exist and be called a vacuum since it's so thin.
Title: Re: Space Flight
Post by: Shmeggley on June 03, 2013, 09:48:48 AM
Anyway, I have no problems with this but  the release from a breach would be the same....no motion of the rocket. It would be a dud.

The release from the breach would be a jet of gas shooting out of the box/rocket, which would behave the same way as it does in air. My point with the pressure difference was basically that from the point of view of the rocket, the exhaust gas is of such high pressure that it makes no difference whether there's air or a vacuum around the rocket; since the difference in pressure is nearly the same, there's only a 15 psi difference, the atmosphere around the rocket is so thin compared to the rocket exhaust that it might as well be a vacuum. Just like for us humans, the pressure up 120,000 feet high, while not zero, might as well not exist and be called a vacuum since it's so thin.
How you can believe that a rockets gases would behave the same on earth as in space is beyond me.

So you think that the law of conservation of momentum, which is a demonstrable fact, applies only on Earth's surface but not above the atmosphere?
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 10:07:54 AM
Anyway, I have no problems with this but  the release from a breach would be the same....no motion of the rocket. It would be a dud.

The release from the breach would be a jet of gas shooting out of the box/rocket, which would behave the same way as it does in air. My point with the pressure difference was basically that from the point of view of the rocket, the exhaust gas is of such high pressure that it makes no difference whether there's air or a vacuum around the rocket; since the difference in pressure is nearly the same, there's only a 15 psi difference, the atmosphere around the rocket is so thin compared to the rocket exhaust that it might as well be a vacuum. Just like for us humans, the pressure up 120,000 feet high, while not zero, might as well not exist and be called a vacuum since it's so thin.
How you can believe that a rockets gases would behave the same on earth as in space is beyond me.

The answer to your question is in my post.

From the point of view of the rocket's exhaust gas, which is of extremely high pressure: atmospheric pressure of 15 psi and vacuum pressure of 0 psi are basically no different for a rocket. To post an actual comparison, nozzle pressure of a rocket's exhaust gas can reach 1000 psi. You see why a 15 psi difference is nearly irrelevant for it?

Just like for a human being, used to 15 psi, a pressure of 1 psi as a few dozen kilometers up, and a pressure of 0 psi as in vacuum, are equally deadly: it makes no difference. You would die exactly the same way if you were exposed to 1 psi as if you were exposed to a vacuum.

The same way for a rocket, used to 1000 psi, 15 psi here or there makes no big difference.
Title: Re: Space Flight
Post by: Fizzy Logic on June 03, 2013, 10:30:16 AM
http://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation (http://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation) describes pretty well how a rocket works in vacuum.

This makes it work into vacuum.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 10:31:12 AM
None of that makes a rocket work in a vacuum.

If you say it doesn't work in a vacuum, then following my post, it shouldn't work in the atmosphere either, since for the rocket it makes no difference. Yet we both know it works in air just fine. So it works in a vacuum too.
Title: Re: Space Flight
Post by: Shmeggley on June 03, 2013, 10:44:31 AM
Anyway, I have no problems with this but  the release from a breach would be the same....no motion of the rocket. It would be a dud.

The release from the breach would be a jet of gas shooting out of the box/rocket, which would behave the same way as it does in air. My point with the pressure difference was basically that from the point of view of the rocket, the exhaust gas is of such high pressure that it makes no difference whether there's air or a vacuum around the rocket; since the difference in pressure is nearly the same, there's only a 15 psi difference, the atmosphere around the rocket is so thin compared to the rocket exhaust that it might as well be a vacuum. Just like for us humans, the pressure up 120,000 feet high, while not zero, might as well not exist and be called a vacuum since it's so thin.
How you can believe that a rockets gases would behave the same on earth as in space is beyond me.

So you think that the law of conservation of momentum, which is a demonstrable fact, applies only on Earth's surface but not above the atmosphere?
When have I said this?

You've just implied that, because you suggest that a rocket should behave differently on Earth and in space. Rockets work by the law of conservation of momentum, which is supposed to be universal. So if you say that they shouldn't work in space then the law would have to be violated in space or for some reason not apply in space.

You have said in these forums that you believe in Newton's laws of motion. The law of conservation of momentum is implied in Newton's laws. So would you like to retract that you believe in Newton's laws or admit that a rocket must work the same wherever it is? That is, it has the same amount of thrust on Earth as in space.
Title: Re: Space Flight
Post by: DuckDodgers on June 03, 2013, 10:46:37 AM
Can someone draw a nice little force diagram for scepti so that he can understand just what is really propelling a rocket?   The fuel turns from solid or liquid into a gas, made up of very tiny particles being accelerated very quickly.   There was so net force before and there has to be zero net force after.   Since these particles were stored in the rocket, when they are accelerated out the rocket exhaust, they must also accelerate the rocket.   One particle accelerates the rocket a miniscule amount,  but there are billions of these particles being ejected during the burn,  causing the rocket to accelerate.  Someone brought up a shotgun analogy which is very appropriate.   The rocket acts like a shotgun that is being fired continuously,  ejecting thousands of particles every fraction of a second.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 10:48:20 AM
Can someone draw a nice little force diagram for scepti so that he can understand just what is really propelling a rocket?   The fuel turns from solid or liquid into a gas, made up of very tiny particles being accelerated very quickly.   There was so net force before and there has to be zero net force after.   Since these particles were stored in the rocket, when they are accelerated out the rocket exhaust, they must also accelerate the rocket.   One particle accelerates the rocket a miniscule amount,  but there are billions of these particles being ejected during the burn,  causing the rocket to accelerate.  Someone brought up a shotgun analogy which is very appropriate.   The rocket acts like a shotgun that is being fired continuously,  ejecting thousands of particles every fraction of a second.

Scintific already posted pressure diagrams of a rocket chamber a few pages back. I guess they didn't work.
Title: Re: Space Flight
Post by: Rama Set on June 03, 2013, 10:54:31 AM
When rockets fire lead shot or ball bearings or even bowling balls from an enclosed chamber, then we can discuss that.
For now, we need to concentrate on rockets "burning" fuel.

Don't you get it? It doesn't matter what is being accelerated, it's a case of how much and how fast.

Rockets expel a far greater mass of gas than a shotgun does of shot, and they expel it at far greater speed too. To achieve that speed, the gas has to be accelerated, which happens inside the rocket (just like the shot is accelerated inside the shotgun). The gas is accelerated toward the exhaust, as that is it's only means of escape, so the rocket is accelerated by a proportional amount in the opposite direction.

Yes, the gas expands rapidly into the vacuum, but it has already done it's work, so that expansion is irrelevant.

If it's a question of retaining the fuel so that it can burn, then all you need to realise is that it takes time for the burnt gasses to expand out of the way, in the meantime they act like a plug, allowing the remaining fuel to burn at a steady rate. When the rocket is not required, internal valves shut off the flow of fuel.
Oh, I get it. No offence to you but you do not get it.

The fuel in your rocket does no work at all until it is expelled from the rockets rear end. On earth, the work is done when it pushes against the atmosphere, "expanding" into it and the atmosphere pushes right back.
In space, you can have a billion ton rocket and it's fuel will expand into space, doing no work, because space will just accept it and beg for more.
The rocket in a vacuum is useless.

Ok, you don't get it. Let me try putting this another way:

Yes, the burning fuel expands into space. Rapidly. But space is only available in one direction: the exhaust. In all other directions, there is the rocket's nozzle. Here's a nice simple diagram of a combustion chamber and nozzle:

(http://upload.wikimedia.org/wikipedia/commons/thumb/5/55/Rocket_thrust.svg/500px-Rocket_thrust.svg.png)

The arrow pointing right represents the escaping gas, the little arrows all around represent the pressure exerted by the gas on the inside of the combustion chamber and nozzle, and the arrow pointing left represents the net resultant force pushing the rocket along.

Actually, I have a question for any actual rocket scientists on here: given that rockets work on a pressure differential, wouldn't that make them more effective in a vacuum?

According to what I read, yes, jet propulsion effectiveness is inveresly proportional to the viscosity of the medium it is working through.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 11:10:01 AM
Anyway, I have no problems with this but  the release from a breach would be the same....no motion of the rocket. It would be a dud.

The release from the breach would be a jet of gas shooting out of the box/rocket, which would behave the same way as it does in air. My point with the pressure difference was basically that from the point of view of the rocket, the exhaust gas is of such high pressure that it makes no difference whether there's air or a vacuum around the rocket; since the difference in pressure is nearly the same, there's only a 15 psi difference, the atmosphere around the rocket is so thin compared to the rocket exhaust that it might as well be a vacuum. Just like for us humans, the pressure up 120,000 feet high, while not zero, might as well not exist and be called a vacuum since it's so thin.
How you can believe that a rockets gases would behave the same on earth as in space is beyond me.

So you think that the law of conservation of momentum, which is a demonstrable fact, applies only on Earth's surface but not above the atmosphere?
When have I said this?

You've just implied that, because you suggest that a rocket should behave differently on Earth and in space. Rockets work by the law of conservation of momentum, which is supposed to be universal. So if you say that they shouldn't work in space then the law would have to be violated in space or for some reason not apply in space.
To gain conservation of momentum in space, you first have to get the rocket to work.

It's the rocket that works by the laws of physics, not the other way round.

Anyway, I'm getting tired of this. You're reverting to the same statements you said three pages ago, and I won't post the same arguments twice, if all you do is ignore them.

I see there's no convincing you until you hop on a rocket yourself. I do hope that will happen within our lifetime.
Title: Re: Space Flight
Post by: Fizzy Logic on June 03, 2013, 11:14:03 AM
http://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation (http://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation) describes pretty well how a rocket works in vacuum.

This makes it work into vacuum.

Please read and work a little bit before stating stupid things.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 11:15:31 AM
Quote
A rocket cannot work against its own fuel, unless that fuel is expended (key word) "against" something.

For the sixth time, that's not how a rocket works. I've said this repeatedly in this thread and even explained why, but you just keep posting the same statement.

Quote
You can't convince me, because I know for a "fact" that rockets cannot work in a vacuum.

Your knowledge of rockets not working in vacuum comes from a misunderstanding of how rockets work in general.
Title: Re: Space Flight
Post by: Shmeggley on June 03, 2013, 11:18:40 AM
Anyway, I have no problems with this but  the release from a breach would be the same....no motion of the rocket. It would be a dud.

The release from the breach would be a jet of gas shooting out of the box/rocket, which would behave the same way as it does in air. My point with the pressure difference was basically that from the point of view of the rocket, the exhaust gas is of such high pressure that it makes no difference whether there's air or a vacuum around the rocket; since the difference in pressure is nearly the same, there's only a 15 psi difference, the atmosphere around the rocket is so thin compared to the rocket exhaust that it might as well be a vacuum. Just like for us humans, the pressure up 120,000 feet high, while not zero, might as well not exist and be called a vacuum since it's so thin.
How you can believe that a rockets gases would behave the same on earth as in space is beyond me.

So you think that the law of conservation of momentum, which is a demonstrable fact, applies only on Earth's surface but not above the atmosphere?
When have I said this?

You've just implied that, because you suggest that a rocket should behave differently on Earth and in space. Rockets work by the law of conservation of momentum, which is supposed to be universal. So if you say that they shouldn't work in space then the law would have to be violated in space or for some reason not apply in space.
To gain conservation of momentum in space, you first have to get the rocket to work.

It's the rocket that works by the laws of physics, not the other way round.

Anyway, I'm getting tired of this. You're reverting to the same statements you said three pages ago, and I won't post the same arguments twice, if all you do is ignore them.

I see there's no convincing you until you hop on a rocket yourself. I do hope that will happen within our lifetime.
You can't convince me, because I know for a "fact" that rockets cannot work in a vacuum.
You and others have been duped by the lies they tell you.

The "fact" that you don't understand how rockets work is not really helping your argument.
Title: Re: Space Flight
Post by: Fizzy Logic on June 03, 2013, 11:19:36 AM
The wiki link is just the tip of the iceberg. I you'd look, you'll find more evidence to support my claims.
Title: Re: Space Flight
Post by: Fizzy Logic on June 03, 2013, 11:21:43 AM
Anyway, I have no problems with this but  the release from a breach would be the same....no motion of the rocket. It would be a dud.

The release from the breach would be a jet of gas shooting out of the box/rocket, which would behave the same way as it does in air. My point with the pressure difference was basically that from the point of view of the rocket, the exhaust gas is of such high pressure that it makes no difference whether there's air or a vacuum around the rocket; since the difference in pressure is nearly the same, there's only a 15 psi difference, the atmosphere around the rocket is so thin compared to the rocket exhaust that it might as well be a vacuum. Just like for us humans, the pressure up 120,000 feet high, while not zero, might as well not exist and be called a vacuum since it's so thin.
How you can believe that a rockets gases would behave the same on earth as in space is beyond me.

So you think that the law of conservation of momentum, which is a demonstrable fact, applies only on Earth's surface but not above the atmosphere?
When have I said this?

You've just implied that, because you suggest that a rocket should behave differently on Earth and in space. Rockets work by the law of conservation of momentum, which is supposed to be universal. So if you say that they shouldn't work in space then the law would have to be violated in space or for some reason not apply in space.
To gain conservation of momentum in space, you first have to get the rocket to work.

It's the rocket that works by the laws of physics, not the other way round.

Anyway, I'm getting tired of this. You're reverting to the same statements you said three pages ago, and I won't post the same arguments twice, if all you do is ignore them.

I see there's no convincing you until you hop on a rocket yourself. I do hope that will happen within our lifetime.
You can't convince me, because I know for a "fact" that rockets cannot work in a vacuum.
You and others have been duped by the lies they tell you.

The "fact" that you don't understand how rockets work is not really helping your argument.
I know exactly how they work and my argument stands 100%. Rockets do not work in a vacuum.

Any data to back this?
Title: Re: Space Flight
Post by: DuckDodgers on June 03, 2013, 11:23:47 AM
If you used even an ounce of common sense you would realize rockets don't require anything for them to push against.   Air is incredibly free flowing and provides very little resistance.   It is a terrible material for something that requires to push on matter to move,  such as a human body.
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 11:32:38 AM
Quote
A rocket cannot work against its own fuel, unless that fuel is expended (key word) "against" something.

For the sixth time, that's not how a rocket works. I've said this repeatedly in this thread and even explained why, but you just keep posting the same statement.

Quote
You can't convince me, because I know for a "fact" that rockets cannot work in a vacuum.

Your knowledge of rockets not working in vacuum comes from a misunderstanding of how rockets work in general.
Your logic is how they work is missing. Sorry to say that but it is.
Don't read the crap, use your common sense.

I did use my common sense while explaining it to you, you may wish to re-read my posts two pages back.
Title: Re: Space Flight
Post by: Fizzy Logic on June 03, 2013, 11:34:18 AM
He has no common sense and he doedńt rely on science! Is there any hope?
Title: Re: Space Flight
Post by: Shmeggley on June 03, 2013, 11:43:27 AM
Quote
A rocket cannot work against its own fuel, unless that fuel is expended (key word) "against" something.

For the sixth time, that's not how a rocket works. I've said this repeatedly in this thread and even explained why, but you just keep posting the same statement.

Quote
You can't convince me, because I know for a "fact" that rockets cannot work in a vacuum.

Your knowledge of rockets not working in vacuum comes from a misunderstanding of how rockets work in general.
Your logic is how they work is missing. Sorry to say that but it is.
Don't read the crap, use your common sense.

I did use my common sense while explaining it to you, you may wish to re-read my posts two pages back.
You are basically saying that a rocket actually pushes itself. Think about what you are saying man.

He's saying that the momentum of the escaping gases is equal and opposite to the momentum of the rocket. If you want to deny Newton's third law, please go ahead.
Title: Re: Space Flight
Post by: Shmeggley on June 03, 2013, 11:54:44 AM
Quote
A rocket cannot work against its own fuel, unless that fuel is expended (key word) "against" something.

For the sixth time, that's not how a rocket works. I've said this repeatedly in this thread and even explained why, but you just keep posting the same statement.

Quote
You can't convince me, because I know for a "fact" that rockets cannot work in a vacuum.

Your knowledge of rockets not working in vacuum comes from a misunderstanding of how rockets work in general.
Your logic is how they work is missing. Sorry to say that but it is.
Don't read the crap, use your common sense.

I did use my common sense while explaining it to you, you may wish to re-read my posts two pages back.
You are basically saying that a rocket actually pushes itself. Think about what you are saying man.

He's saying that the momentum of the escaping gases is equal and opposite to the momentum of the rocket. If you want to deny Newton's third law, please go ahead.
But...but...they don't quite use Newtons 3rd law do they.

But if you take a 400 kg rocket full of 100 kg of fuel, starting from zero momentum, then ignite the fuel and expel it all from the end of the rocket at 100 m/s, then by Newton's 3rd law the rocket has to be going at 25 m/s (if I calculated all that right) in the opposite direction you shot the fuel. Nobody is using Newton's 3rd law, it just describes what must happen in this situation.
Title: Re: Space Flight
Post by: Rama Set on June 03, 2013, 11:57:15 AM
Anyway, I have no problems with this but  the release from a breach would be the same....no motion of the rocket. It would be a dud.

The release from the breach would be a jet of gas shooting out of the box/rocket, which would behave the same way as it does in air. My point with the pressure difference was basically that from the point of view of the rocket, the exhaust gas is of such high pressure that it makes no difference whether there's air or a vacuum around the rocket; since the difference in pressure is nearly the same, there's only a 15 psi difference, the atmosphere around the rocket is so thin compared to the rocket exhaust that it might as well be a vacuum. Just like for us humans, the pressure up 120,000 feet high, while not zero, might as well not exist and be called a vacuum since it's so thin.
How you can believe that a rockets gases would behave the same on earth as in space is beyond me.

So you think that the law of conservation of momentum, which is a demonstrable fact, applies only on Earth's surface but not above the atmosphere?
When have I said this?

You've just implied that, because you suggest that a rocket should behave differently on Earth and in space. Rockets work by the law of conservation of momentum, which is supposed to be universal. So if you say that they shouldn't work in space then the law would have to be violated in space or for some reason not apply in space.
To gain conservation of momentum in space, you first have to get the rocket to work.

It's the rocket that works by the laws of physics, not the other way round.

Anyway, I'm getting tired of this. You're reverting to the same statements you said three pages ago, and I won't post the same arguments twice, if all you do is ignore them.

I see there's no convincing you until you hop on a rocket yourself. I do hope that will happen within our lifetime.
You can't convince me, because I know for a "fact" that rockets cannot work in a vacuum.
You and others have been duped by the lies they tell you.

You either do not know what a fact is, or you are lying, or you have conducted experiments involving rocket technology in a vacuum and do not like to talk about it. 

Which is it?
Title: Re: Space Flight
Post by: Rama Set on June 03, 2013, 12:05:54 PM
Anyway, I have no problems with this but  the release from a breach would be the same....no motion of the rocket. It would be a dud.

The release from the breach would be a jet of gas shooting out of the box/rocket, which would behave the same way as it does in air. My point with the pressure difference was basically that from the point of view of the rocket, the exhaust gas is of such high pressure that it makes no difference whether there's air or a vacuum around the rocket; since the difference in pressure is nearly the same, there's only a 15 psi difference, the atmosphere around the rocket is so thin compared to the rocket exhaust that it might as well be a vacuum. Just like for us humans, the pressure up 120,000 feet high, while not zero, might as well not exist and be called a vacuum since it's so thin.
How you can believe that a rockets gases would behave the same on earth as in space is beyond me.

So you think that the law of conservation of momentum, which is a demonstrable fact, applies only on Earth's surface but not above the atmosphere?
When have I said this?

You've just implied that, because you suggest that a rocket should behave differently on Earth and in space. Rockets work by the law of conservation of momentum, which is supposed to be universal. So if you say that they shouldn't work in space then the law would have to be violated in space or for some reason not apply in space.
To gain conservation of momentum in space, you first have to get the rocket to work.

It's the rocket that works by the laws of physics, not the other way round.

Anyway, I'm getting tired of this. You're reverting to the same statements you said three pages ago, and I won't post the same arguments twice, if all you do is ignore them.

I see there's no convincing you until you hop on a rocket yourself. I do hope that will happen within our lifetime.
You can't convince me, because I know for a "fact" that rockets cannot work in a vacuum.
You and others have been duped by the lies they tell you.

You either do not know what a fact is, or you are lying, or you have conducted experiments involving rocket technology in a vacuum and do not like to talk about it. 

Which is it?
I've conducted rocket tests in a vacuum and I don't like to talk about it. Do you think I'm lying?

Of course I do.  I added on the third choice for completeness only.  Its perfectly obivous from your posting history you do not have a clue about how to go abou that.
Title: Re: Space Flight
Post by: Fizzy Logic on June 03, 2013, 12:08:58 PM
Of course he is lying... But he can still prove us wrong by showing us his data.
Title: Re: Space Flight
Post by: DuckDodgers on June 03, 2013, 12:14:42 PM
Maybe we should tackle this from another angle and start with some basics.   Do you believe that matter is not destroyed when changing states from liquid to gas?
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 12:20:04 PM
Quote
A rocket cannot work against its own fuel, unless that fuel is expended (key word) "against" something.

For the sixth time, that's not how a rocket works. I've said this repeatedly in this thread and even explained why, but you just keep posting the same statement.

Quote
You can't convince me, because I know for a "fact" that rockets cannot work in a vacuum.

Your knowledge of rockets not working in vacuum comes from a misunderstanding of how rockets work in general.
Your logic is how they work is missing. Sorry to say that but it is.
Don't read the crap, use your common sense.

I did use my common sense while explaining it to you, you may wish to re-read my posts two pages back.
You are basically saying that a rocket actually pushes itself. Think about what you are saying man.

No, Scepti, I'm saying that the gas from the burned fuel is what pushes the rocket.
Title: Re: Space Flight
Post by: Fizzy Logic on June 03, 2013, 12:29:31 PM
How about this: http://answers.yahoo.com/question/index?qid=20071110114103AAz61PN (http://answers.yahoo.com/question/index?qid=20071110114103AAz61PN)
Title: Re: Space Flight
Post by: Rama Set on June 03, 2013, 12:29:57 PM
Anyway, I have no problems with this but  the release from a breach would be the same....no motion of the rocket. It would be a dud.

The release from the breach would be a jet of gas shooting out of the box/rocket, which would behave the same way as it does in air. My point with the pressure difference was basically that from the point of view of the rocket, the exhaust gas is of such high pressure that it makes no difference whether there's air or a vacuum around the rocket; since the difference in pressure is nearly the same, there's only a 15 psi difference, the atmosphere around the rocket is so thin compared to the rocket exhaust that it might as well be a vacuum. Just like for us humans, the pressure up 120,000 feet high, while not zero, might as well not exist and be called a vacuum since it's so thin.
How you can believe that a rockets gases would behave the same on earth as in space is beyond me.

So you think that the law of conservation of momentum, which is a demonstrable fact, applies only on Earth's surface but not above the atmosphere?
When have I said this?

You've just implied that, because you suggest that a rocket should behave differently on Earth and in space. Rockets work by the law of conservation of momentum, which is supposed to be universal. So if you say that they shouldn't work in space then the law would have to be violated in space or for some reason not apply in space.
To gain conservation of momentum in space, you first have to get the rocket to work.

It's the rocket that works by the laws of physics, not the other way round.

Anyway, I'm getting tired of this. You're reverting to the same statements you said three pages ago, and I won't post the same arguments twice, if all you do is ignore them.

I see there's no convincing you until you hop on a rocket yourself. I do hope that will happen within our lifetime.
You can't convince me, because I know for a "fact" that rockets cannot work in a vacuum.
You and others have been duped by the lies they tell you.

You either do not know what a fact is, or you are lying, or you have conducted experiments involving rocket technology in a vacuum and do not like to talk about it. 

Which is it?
I've conducted rocket tests in a vacuum and I don't like to talk about it. Do you think I'm lying?

Of course I do.  I added on the third choice for completeness only.  Its perfectly obivous from your posting history you do not have a clue about how to go abou that.
Do you feel better now?

Quite.  Thanks!
Title: Re: Space Flight
Post by: Fizzy Logic on June 03, 2013, 12:39:08 PM
You cannot understand even a simple explanation?
Title: Re: Space Flight
Post by: icanbeanything on June 03, 2013, 12:45:59 PM
Can you just elaborate a little bit here, I think we might be getting somewhere.

I sure hope so, since I already elaborated on this same thing two pages back.

Basically, as the fuel burns, gas is generated inside the rocket's chamber. Savvy? This gas has a huge instantaneous pressure, pushing on the walls of the chamber, except for the exhaust nozzle, since there's no wall there to push against. This causes two things: ONE, the net force of the pressure pushes the rocket forward, since there is no force pushing against the exhaust nozzle of the rocket. TWO, the gas leaves the back of the rocket.

Notice that at no point in this was anything from the outside involved. The "pushing" of the rocket by the gas happens before the gas leaves the nozzle of the rocket, and before it has any chance to encounter air.
Title: Re: Space Flight
Post by: icanbeanything on June 04, 2013, 02:32:58 AM
Can you just elaborate a little bit here, I think we might be getting somewhere.

I sure hope so, since I already elaborated on this same thing two pages back.

Basically, as the fuel burns, gas is generated inside the rocket's chamber. Savvy? This gas has a huge instantaneous pressure, pushing on the walls of the chamber, except for the exhaust nozzle, since there's no wall there to push against. This causes two things: ONE, the net force of the pressure pushes the rocket forward, since there is no force pushing against the exhaust nozzle of the rocket. TWO, the gas leaves the back of the rocket.

Notice that at no point in this was anything from the outside involved. The "pushing" of the rocket by the gas happens before the gas leaves the nozzle of the rocket, and before it has any chance to encounter air.
So basically what you are saying is. It's like someone in an alley way using their hands and feet to hoist themselves up by using the side walls as leverage . Is this what you are basically getting at, because this is how it seems to me.

Truly sorry if that's how it seems to you. I'm telling you it's not like that. But I don't see any other way to explain it. At this point only a live demonstration would work for you. Are there any physics universities nearby where you live? You could ask them if they have the time, to show you a vacuum chamber and allow you to put a balloon in it. See how it flies around in a vacuum.

By the way, as a technicality: the "vacuum" of outer space isn't really a perfect vacuum. It has some particles in it, and its pressure is above zero. Vacuum chambers can create much lower pressures than what is in space.
Title: Re: Space Flight
Post by: icanbeanything on June 04, 2013, 03:19:53 AM
I don't know what space is. I'm going on what they tell us space is, as in a virtual vacuum...so basically I have to make my views based on that.
You won't see a balloon fly around in a vacuum, except when it goes pop..
The reason it will move then is because of the elasticity nothing more.

Your rocket in a vacuum will expend all of it's energy, (fuel) before it has the chance to do any work...which is to move the rocket.
By your reasoning, there is no legitimate reason for a rocket to ignite it's fuel in the vacuum of space..but they appear to do just that...why?

The reason is simple...rockets do not work in space, never have and likely never will.
We are on this earth and we stay on this earth....Nobody gets off and nobody gets on... it's our floor of the sky and anything that gets to live on it...grows on it.

The little tin things we send into the sky can go high and then fall back to earth.
The massive rockets like the Saturn V and the shuttle are all CGI and models.
Anything of that size with the fuel we use...would not leave the ground and would simply blow to smithereens if such a thing were possible to attempt to be made and fired up.

The launches we see in real time are simply ballistic missile launches that expend their fuel in minutes and are spent..to fall back into the sea, where they are picked up out of sight of prying eyes.

There is absolutely nothing man made in space...not even a screw.

You didn't answer my question... are there any universities in your area where you may find a vacuum chamber? I'm sure they'll let you put a balloon in it when the chamber is not in use for experiments. Just say it's for a YouTube experiment video of a balloon in vacuum. They'd most likely be happy to help.

Quote
The little tin things we send into the sky can go high and then fall back to earth.

So where's all the footage and witness accounts of them falling back to Earth right after launch? Again, such a huge rocket falling from the sky would definitely be impossible to cover up by NASA. Once more than 10 people see it, you're bound to have accounts of it. Not to mention if it falls next to a cruise line or, god forbid, over a city.
Title: Re: Space Flight
Post by: icanbeanything on June 04, 2013, 03:32:31 AM
The university?
Title: Re: Space Flight
Post by: Scintific Method on June 04, 2013, 03:51:54 AM
Back to my shotgun analogy: different weight loads recoil different amounts. This has nothing to do with pressure, as they all push on the same amount of air with the same amount of force. It has everything to do with the mass of the projectile(s) being propelled out of the barrel.

Again, this is direct evidence of Newton's 3rd law, which is what rockets operate on, and why they are more effective in a vacuum, not less. And before you say "yes, but rockets don't fire shot", realise that all matter (including gas) has mass, and the mass is what matters. (No pun intended!)

Oh, and going to a university and doing the balloon in a vacuum chamber experiment suggested by icanbeanything would be well worth your time. Just don't blow it up too full to start with.
Title: Re: Space Flight
Post by: icanbeanything on June 04, 2013, 04:30:47 AM
Gas has mass but is not a solid like lead shot or a bowling ball or whatever else.
This is the bullshit that scientists give out to explain why a rocket will work in a vacuum.

Solid, liquid, gas, plasma, it doesn't matter, it's still made of the same particles, and it's those particles that give it mass.

Anyway, no response on the try-it-out-yourself thing? Is there a reason why you don't want to answer that?
Title: Re: Space Flight
Post by: Manarq on June 04, 2013, 04:41:50 AM
I think it might be time for this diagram.

(http://files.abovetopsecret.com/images/member/c3c311648c22.jpg)
Title: Re: Space Flight
Post by: Scintific Method on June 04, 2013, 04:43:54 AM
Gas has mass but is not a solid like lead shot or a bowling ball or whatever else.

Doesn't matter, the mass is the important part.

This is the science that scientists give out to explain why a rocket will work in a vacuum.

Fixed that for you.

Do you realise how much mass you would need to throw away from you to propel yourself on a chair with any meaning on a level floor.

Yes, I do.

Do you realise how much mass you would have to throw below you to make you raise off the floor just one foot.

Yes, I do.

Transfer that your your rocket that simply supposedly just uses mass to propel it upwards, especially something like the shuttle and you will quickly realise that not only would it blow up but it wouldn't even get off the ground...and if it did...it's fuel would be spend before it had time to get a few thousand feet into the sky...let alone anywhere near space.

There's a lot of careful design, which I do understand by the way, that goes into making sure they don't just explode on takeoff. It took a lot of trial and error to learn what was needed too. Oh, and have you seen the size of the fuel tanks these things use? They're freakin huge!

In space if it was ever able to...which is wasn't...it would be a dud.

No, it wouldn't. If you actually took the trouble to understand physics, instead of dismissing it simply because you don't understand it, all this would make a lot more sense.
Title: Re: Space Flight
Post by: icanbeanything on June 04, 2013, 04:57:53 AM
Gas has mass but is not a solid like lead shot or a bowling ball or whatever else.
This is the bullshit that scientists give out to explain why a rocket will work in a vacuum.

Solid, liquid, gas, plasma, it doesn't matter, it's still made of the same particles, and it's those particles that give it mass.

Anyway, no response on the try-it-out-yourself thing? Is there a reason why you don't want to answer that?
I know what would happen but firstly..tell me how to put a blown up , open ended balloon inside a vacuum chamber.

You blow it up a bit (not as much as you would normally), tie a spring-release or a specific pull-to-untie knot on the mouth. They you put it in the chamber, it sucks the air out, and they usually have ways of manipulating objects in the chamber. Of course, it depends on what kind of chamber it is, but it should be doable with a little tinkering in any chamber.

Once the balloon is in, and vacuum is attained, it will grow in size a lot, this is why it shouldn't be very inflated beforehand, or it will pop at this stage. Once there's a vacuum, you just press the spring release or pull the string or whatever you have to do, to open up the balloon. If you can't think of a way to do this, the people there will probably help you out.

That's it! Don't forget to film it with something!
Title: Re: Space Flight
Post by: Manarq on June 04, 2013, 05:04:13 AM

That's akin to blowing your own sail on a boat.
You should know this is absolutely impossible and if not...go and get into your car...don't start it..just sit in the drivers seat and push your car by slamming your face off of the windscreen, see how far you get on a level surface.

Oh, i you want to, you can have a friend in as well and he/she can throw heavy bowling ball out of the back window as you are doing this...see how far this gets you.

If you want to be extreme, then get your friend to get a bazooka and fire it out of the back window....this may get you slightly moving but will probably wreck your car after 1 minutes worth of firing it.

I'm not trying to be funny here by the way...this is what you are telling me that a rocket does.
If someone is throwing heavy balls out of the back of the car then yes it would give it some energy in the opposite direction. Probably not enough to overcome the friction with the ground but it should be measurable.

As for the diagram it's just about as simple a rocket as you can get, imagine a balloon that you have blown up. There is air inside the balloon at a higher pressure than the air outside it. While you hold the end shut the air is pressing on all "sides" of the balloon equally and this is why it is bigger than if it's just open to the air, the pressure inside the balloon  pressing out is stretching it.
Now if you let go of the blown up balloon it doesn't immediately revert to it's original size, rather it shrinks at a rate equal to how fast the air can come out. While the balloon is shrinking there is still pressure being exerted on the sides of the balloon and the pressures all cancel each other out except for the one opposite the nozzle where the air is coming out.

Title: Re: Space Flight
Post by: icanbeanything on June 04, 2013, 05:14:50 AM
I know exactly what would happen with it and one thing it won't do is fly about.

Well, I know exactly that it would fly about. I've done this - well, not with balloons, but with other things that work just like a rocket - and it definitely will fly about. Why don't you try it? This one seriously doesn't require anything else, just a balloon, IF there's a university nearby. I'm sure they'll help you do it, just ask if they have the time and say you want to film it for YouTube.

Do not ask the secretaries or the dean... Just ask where the laboratories are and approach a lab practicant, ask them for the experiment itself.
Title: Re: Space Flight
Post by: Rama Set on June 04, 2013, 05:20:37 AM
I think it might be time for this diagram.

(http://files.abovetopsecret.com/images/member/c3c311648c22.jpg)
That's akin to blowing your own sail on a boat.
You should know this is absolutely impossible and if not...go and get into your car...don't start it..just sit in the drivers seat and push your car by slamming your face off of the windscreen, see how far you get on a level surface.

Oh, if you want to, you can have a friend in as well and he/she can throw heavy bowling ball out of the back window as you are doing this...see how far this gets you.

If you want to be extreme, then get your friend to get a bazooka and fire it out of the back window....this may get you slightly moving but will probably wreck your car after 1 minutes worth of firing it.

I'm not trying to be funny here by the way...this is what you are telling me that a rocket does.

Lol!  Are you saying that throwing a bowling ball or breathing generates as much continuous force as a jet engine?  Analogies are supposed to be good comparisons, not intentionally trivializing of the original situation. Your analogy is basically a lie Pinocchio...
Title: Re: Space Flight
Post by: icanbeanything on June 04, 2013, 05:23:09 AM
I know exactly what would happen with it and one thing it won't do is fly about.

Well, I know exactly that it would fly out. I've done this - well, not with balloons, but with other things that work just like a rocket - and it definitely will fly about. Why don't you try it? This one seriously doesn't require anything else, just a balloon, IF there's a university nearby. I'm sure they'll help you do it, just ask if they have the time and say you want to film it for YouTube.

Do not ask the secretaries or the dean... Just ask where the laboratories are and approach a lab practicant, ask them for the experiment itself.
So what have you experimented with with the things that work just like a rocket?

One example would be measuring the thrust generated by a special laser, testing for laser propulsion. Experiment done in a vacuum. You turn on the laser, the beam comes out one end, and it pushes the device the other way, with a very small force that I had to measure.

Don't mind all this, just try what I suggested. If they're willing to help you, all you need is a balloon, they'll take care of the rest.
Title: Re: Space Flight
Post by: Manarq on June 04, 2013, 05:24:07 AM

That's akin to blowing your own sail on a boat.
You should know this is absolutely impossible and if not...go and get into your car...don't start it..just sit in the drivers seat and push your car by slamming your face off of the windscreen, see how far you get on a level surface.

Oh, i you want to, you can have a friend in as well and he/she can throw heavy bowling ball out of the back window as you are doing this...see how far this gets you.

If you want to be extreme, then get your friend to get a bazooka and fire it out of the back window....this may get you slightly moving but will probably wreck your car after 1 minutes worth of firing it.

I'm not trying to be funny here by the way...this is what you are telling me that a rocket does.
If someone is throwing heavy balls out of the back of the car then yes it would give it some energy in the opposite direction. Probably not enough to overcome the friction with the ground but it should be measurable.

As for the diagram it's just about as simple a rocket as you can get, imagine a balloon that you have blown up. There is air inside the balloon at a higher pressure than the air outside it. While you hold the end shut the air is pressing on all "sides" of the balloon equally and this is why it is bigger than if it's just open to the air, the pressure inside the balloon  pressing out is stretching it.
Now if you let go of the blown up balloon it doesn't immediately revert to it's original size, rather it shrinks at a rate equal to how fast the air can come out. While the balloon is shrinking there is still pressure being exerted on the sides of the balloon and the pressures all cancel each other out except for the one opposite the nozzle where the air is coming out.
This just proves that the balloon is pushing against the air under it by use of the force of the elasticated shell of it forcing it out.
If this is your rocket, then this is proof that your rocket needs an atmosphere.
The only difference here is, the balloon is expelling the air by elasticated means and a rocket does it by pressure of oxygen in a fuel mix.

End result...fine on earth...no good for space.
Please draw me (or reference if you've already done one) one of your famous diagrams to show how the force is being applied to the balloon to push it forwards.
Title: Re: Space Flight
Post by: Scintific Method on June 04, 2013, 05:30:43 AM
The physics you are being taught is Pinocchio physics. I'm not saying you are a liar though, all you have done is what many have done and bought into it.

Unlike you scepti, I have actually done numerous experiments which demonstrate the laws of physics that you deny exist.


This just proves that the balloon is pushing against the air under it by use of the force of the elasticated shell of it forcing it out.

The elasticity of the balloon is actually expelling the air you used to fill the balloon, not pushing on the atmosphere outside it. There doesn't need to be an atmosphere outside the balloon for this to work, as it already contains its propellant.

Just go and do ican's experiment, you might actually learn something. And don't keep saying "I know what will happen", because you haven't seen what will happen, so go do it so you can actually see for yourself!
Title: Re: Space Flight
Post by: icanbeanything on June 04, 2013, 06:09:38 AM
I know exactly what would happen with it and one thing it won't do is fly about.

Well, I know exactly that it would fly out. I've done this - well, not with balloons, but with other things that work just like a rocket - and it definitely will fly about. Why don't you try it? This one seriously doesn't require anything else, just a balloon, IF there's a university nearby. I'm sure they'll help you do it, just ask if they have the time and say you want to film it for YouTube.

Do not ask the secretaries or the dean... Just ask where the laboratories are and approach a lab practicant, ask them for the experiment itself.
So what have you experimented with with the things that work just like a rocket?

One example would be measuring the thrust generated by a special laser, testing for laser propulsion. Experiment done in a vacuum. You turn on the laser, the beam comes out one end, and it pushes the device the other way, with a very small force that I had to measure.

Don't mind all this, just try what I suggested. If they're willing to help you, all you need is a balloon, they'll take care of the rest.
So what's this laser experiment and why does it work and what does it prove about rockets in a vacuum.
Who has these laser fuel rockets?

Nobody uses these for propulsion yet. It's research only for now. But it works just like a classical rocket. Have you ever seen or used a laser pointer? That's basically it. You turn on the laser, and it's pushed the opposite way by the exiting beam. Of course, you can't feel this when using a laser pointer. But you can if you construct an experiment around it.

What happens is, the photons act as the propulsion, just like the exiting gas would in a rocket. The photons carry energy, and thus, momentum with themselves, and as we've said before, that causes the laser to be pushed the opposite way. Exactly like a rocket.

It proves rockets work in a vacuum because it too worked in a vacuum. Can you not draw the parallel yourself?

Anyway, go do the balloon experiment, you won't regret it.
Title: Re: Space Flight
Post by: icanbeanything on June 04, 2013, 06:14:49 AM
I thought Photons don't have any mass.

They don't. But they have energy and momentum.
Title: Re: Space Flight
Post by: icanbeanything on June 04, 2013, 06:21:10 AM
I thought Photons don't have any mass.

They don't. But they have energy and momentum.
Wait a minute...you can't have it both ways...it's either mass that's doing the amazing rocket trick or it's not...which is it?

You have to realize, in physics, things are related. There is an order.

It's momentum doing it. The conservation of momentum is what makes a rocket work.

But since any mass, that isn't at rest, has momentum, it's also true that any mass does the trick. It means the same thing.

In my initial explanation I said mass, because I didn't want to invoke laws like the conservation of momentum, since you have an aversion to those.
Title: Re: Space Flight
Post by: icanbeanything on June 04, 2013, 06:31:29 AM
I thought Photons don't have any mass.

They don't. But they have energy and momentum.
Wait a minute...you can't have it both ways...it's either mass that's doing the amazing rocket trick or it's not...which is it?

You have to realize, in physics, things are related. There is an order.

It's momentum doing it. The conservation of momentum is what makes a rocket work.

But since any mass, that isn't at rest, has momentum, it's also true that any mass does the trick. It means the same thing.

In my initial explanation I said mass, because I didn't want to invoke laws like the conservation of momentum, since you have an aversion to those.
So the bowling ball and wheeled chair is a fabrication for the explanation of how rockets work. Well ok, at least that's one sack of crap out of the way..it's just a case of destroying the rest..which I will.

That's the conclusion you drew? I don't see how. I haven't been bowling for a while, but do bowling balls not have mass now?
Title: Re: Space Flight
Post by: Manarq on June 04, 2013, 06:52:12 AM

Please draw me (or reference if you've already done one) one of your famous diagrams to show how the force is being applied to the balloon to push it forwards.
Air pressure which is higher than the air pressure outside of it, so wants to get out and equalize with it.
The only two ways it can do this is to burst the balloon or come out of the bottom where the higher pressure air tries to push through the air under the balloon and the air under it creates resistance creating a push on push...a push of war rather than a tug of war.


To put it into another context, it's like the Roman army against the Spartans, with Kirk Douglas and Tony Curtis in their mini dresses and snazzy sandals, (copied by millions of females today)...

Ok, what happens is...the Spartans...(balloon air pressure)..attack the Romans...(wider atmosphere) and try to drive right through them but as the Roman front gets breached, the back line crowd in and force themselves against the rampant Spartans and because the Roman army is inexhaustible it keeps pushing the Spartans further back... and as much as the Spartans push against the Romans, the Romans push back more , resulting in the Spartans getting weaker and weaker as they are pushed all the way back up the hill until they finally run out of fight and all tumble back down through the masses of Romans who part their way for the tumbling Spartans.

I'm spartacus.  >o< ;D
The film you're mis-referencing here had nothing to do with the Spartans, for a start Spartacus was Thracian, trained as a gladiator and led a slave uprising.

As for how the balloon moves please draw a diagram showing where the force is acting upon the balloon in order to move it forwards. A force has to be acting upon the balloon to move it, you're saying that the air escaping the balloon meeting the air outside the balloon creates the force but how is this transferred to the balloon?
Title: Re: Space Flight
Post by: Manarq on June 04, 2013, 07:22:43 AM

The film you're mis-referencing here had nothing to do with the Spartans, for a start Spartacus was Thracian, trained as a gladiator and led a slave uprising.

As for how the balloon moves please draw a diagram showing where the force is acting upon the balloon in order to move it forwards. A force has to be acting upon the balloon to move it, you're saying that the air escaping the balloon meeting the air outside the balloon creates the force but how is this transferred to the balloon?
Think of being in a swimming pool with a blown up balloon. Rest it on the water  and it floats right?

Start to drag that balloon under the water  and the balloon wants to release from your grip, right?
The reason it does this, is because the water is denser than it and is squashing it and the balloon doesn't appreciate it, so it struggles free and shoots up.

This only happens because you forced that balloon into this situation but the reality is... the water does not like the balloon and decided to push him out of his space by crowding around it and bullying it, yet you holding that balloon, forced that balloon to struggle against the bullies.

Your force....your hand= fuel against the force of the water pushing back= the atmosphere.
You didn't answer the question, where is the force acting on the balloon? In your very poor example my hand would be in physical contact with the balloon, so where is the "fighting" air pushing on the balloon?
Title: Re: Space Flight
Post by: Manarq on June 04, 2013, 07:36:56 AM

The film you're mis-referencing here had nothing to do with the Spartans, for a start Spartacus was Thracian, trained as a gladiator and led a slave uprising.

As for how the balloon moves please draw a diagram showing where the force is acting upon the balloon in order to move it forwards. A force has to be acting upon the balloon to move it, you're saying that the air escaping the balloon meeting the air outside the balloon creates the force but how is this transferred to the balloon?
Think of being in a swimming pool with a blown up balloon. Rest it on the water  and it floats right?

Start to drag that balloon under the water  and the balloon wants to release from your grip, right?
The reason it does this, is because the water is denser than it and is squashing it and the balloon doesn't appreciate it, so it struggles free and shoots up.

This only happens because you forced that balloon into this situation but the reality is... the water does not like the balloon and decided to push him out of his space by crowding around it and bullying it, yet you holding that balloon, forced that balloon to struggle against the bullies.

Your force....your hand= fuel against the force of the water pushing back= the atmosphere.
You didn't answer the question, where is the force acting on the balloon? In your very poor example my hand would be in physical contact with the balloon, so where is the "fighting" air pushing on the balloon?
The fight is your hand forcing the balloon to fight against the water...once you release your hand, the balloon lays on top of the water just as a spent rocket would after expending all of it's fuel , meaning the pull of your hand.

Look at what I wrote very carefully and you will understand what I'm saying if you convert it to what the balloon is doing.
I've started the picture for you, just draw an arrow on showing me where the force is acting on the balloon.
(http://img822.imageshack.us/img822/3948/balloon1q.jpg) (http://imageshack.us/photo/my-images/822/balloon1q.jpg/)

Uploaded with ImageShack.us (http://imageshack.us)
Title: Re: Space Flight
Post by: icanbeanything on June 04, 2013, 11:27:17 AM
That's cool, but you forgot the air on the inside also pushing on the balloon's wall, opposing the force from outside.

In order for air to be exiting the balloon, inside pressure must be greater than outside pressure. So the inside arrows would be "stronger" than the outside arrows.

(http://img7.imageshack.us/img7/3948/balloon1q.jpg)

Like this.

Now, since the inside pressure is greater, the force pushing from inside is greater. So the blue arrows are "stronger" and if you add the blue arrows to the black arrows, you get the red arrows:
(http://img46.imageshack.us/img46/3341/balloon1q1.jpg)
Title: Re: Space Flight
Post by: icanbeanything on June 04, 2013, 11:36:40 AM
Now if you look at the red arrows, they're everywhere on the balloon except for the back, where the mouth is, since there's no wall to push against there (and consequently, it's where the air inside is leaving.)

The arrows pushing opposite sides of the balloon cancel out, since they're the same strength.
Here, green and green, respectively black and black cancel.
But there's nothing to cancel out the top part where force is pushing, since the opposite side has no wall, thus no arrow.
(http://img849.imageshack.us/img849/1777/bq1.jpg)

That single red arrow left gives you the overall resultant force. That force gives you the direction your balloon will accelerate.

Finally, consider what happens with all this if there's a vacuum outside.

If there's a vacuum outside, it means there are no black arrows to begin with, right? But the blue arrows are still there. So ultimately, the red arrows will just be "stronger", since there's no outside opposition. The reds cancel out just the same way, except for the top one, because there's no arrow on the opposite side.

The final arrow will still be there on the top, and will cause your balloon to accelerate even in a vacuum.
Title: Re: Space Flight
Post by: icanbeanything on June 04, 2013, 11:54:55 AM
The reason a balloon works this way is due to the elasticity acting on the air, so your analogy in the vacuum is wrong.

Okay, look at the image, and now imagine it's not a balloon, it's a steel sphere. What's different about the action of the arrows?

Nothing. The elasticity of the balloon isn't even accounted for in this diagram.
Title: Re: Space Flight
Post by: Rama Set on June 04, 2013, 12:04:46 PM
The reason a balloon works this way is due to the elasticity acting on the air, so your analogy in the vacuum is wrong.

Okay, look at the image, and now imagine it's not a balloon, it's a steel sphere. What's different about the action of the arrows?
I know what you are getting at but that is not how rockets work.
Can you imagine if that was employed in a big fuel tank like that on the fake shuttle.
By your analogy, the fuel coming from that tank would also push that tank upwards but the tank is external from the fake shuttle.
Seriously they have filled you full of crap about how a rocket works, that is why it's not easy to explain it to rational thinking people the way they do...because it simply does not work in how they say it does.

The shuttle is moored to the solid rocket boosters.
Title: Re: Space Flight
Post by: icanbeanything on June 04, 2013, 12:05:07 PM
The reason a balloon works this way is due to the elasticity acting on the air, so your analogy in the vacuum is wrong.

Okay, look at the image, and now imagine it's not a balloon, it's a steel sphere. What's different about the action of the arrows?
I know what you are getting at but that is not how rockets work.
Can you imagine if that was employed in a big fuel tank like that on the fake shuttle.
By your analogy, the fuel coming from that tank would also push that tank upwards but the tank is external from the fake shuttle.
Seriously they have filled you full of crap about how a rocket works, that is why it's not easy to explain it to rational thinking people the way they do...because it simply does not work in how they say it does.

The fuel tank is external, but the diagram is for the engine itself, where the fuel is ignited. That is on the bottom of the rocket/shuttle.

So, with a fuel tank, imagine the same diagram, but with a small feeding nozzle coming from somewhere, constantly replenishing the gas that leaves the bottom (into space).
Title: Re: Space Flight
Post by: icanbeanything on June 04, 2013, 12:21:48 PM
This changes every five minutes.
Now which is it...Is it the fuel in the tank that pushes the rocket... or the fuel at the bottom of the rocket which has nothing to do with the tank.

Be clear here, otherwise we will have to conclude that rockets do not work in space and you have been told lies and believed them for no apparent reason.

Nothing is changing, it's just you seeing it wrong. In case of a simple balloon, the fuel tank, rocket, and engine are the same thing, the balloon itself. This is where your confusion comes from. A modern rocket isn't just a big chamber.

There's a tank to hold the fuel. This is just to hold the fuel, it's not where the propulsion is generated. This fuel is fed into the engine, which has a fuel burning chamber. This chamber is essentially what you see on the diagram. It is in this chamber that the thrust is generated by expanding gas, the same way it is in the diagram. The expanding gas is pushing on the top of the burning chamber's wall. The chamber is attached to the rocket, so all the rocket is pushed therefore.

The fuel tank of a rocket is just to keep the engine chamber constantly fed with more gas to expand. It's like you attached a CO2 tank to the side of the balloon through a valve and nozzle, to keep feeding the balloon more gas as it is constantly being expelled from it.
Title: Re: Space Flight
Post by: icanbeanything on June 04, 2013, 12:52:02 PM
Scepti, what is propelling the rocket is that those expanding gases are pushing the TOP of the inner chamber from where they're coming from. Like in the diagram. Think of the diagram. The gas inside is expanding every way, but there's only one way it can exit, and that's below. There's no wall below, there's the open neck of the chamber, so the force of the expanding gas doesn't cancel out the top component. The top component remains, pushing the rocket.
Title: Re: Space Flight
Post by: Manarq on June 04, 2013, 02:55:26 PM
Thanks for the diagram Scepti, I still can't see where the upward force is being applied as air pressure acts on the balloon equally from all directions.

Anyway maybe if we look at a mechanical application of the forces involved, do you know how the internal combustion engine works?
Title: Re: Space Flight
Post by: hoppy on June 04, 2013, 04:04:30 PM
Scepti, are there any others espousing that rockets do not work in a vacuum? I must say, I somewhat believe you. Although I am not totally convinced. Perhaps another's explanation may help me and others to comprehend the futility of rocket propulsion in space.
Title: Re: Space Flight
Post by: markjo on June 04, 2013, 06:06:48 PM
Here is someone else who seems to have thought the whole "rockets can't work in a vacuum" through a little better than Sceptimatic.  He's still wrong, but at least he tries to give specific reasons.
http://cluesforum.info/viewtopic.php?f=23&t=1632&sid=859ccbe6e2bec4c0fa4419addac7bd92 (http://cluesforum.info/viewtopic.php?f=23&t=1632&sid=859ccbe6e2bec4c0fa4419addac7bd92)
Title: Re: Space Flight
Post by: Manarq on June 05, 2013, 02:27:54 AM
Here is someone else who seems to have thought the whole "rockets can't work in a vacuum" through a little better than Sceptimatic.  He's still wrong, but at least he tries to give specific reasons.
http://cluesforum.info/viewtopic.php?f=23&t=1632&sid=859ccbe6e2bec4c0fa4419addac7bd92 (http://cluesforum.info/viewtopic.php?f=23&t=1632&sid=859ccbe6e2bec4c0fa4419addac7bd92)
Interesting read Markjo, the persons statement of "I'm not going to use equations" is very Sceptimaticy.
Title: Re: Space Flight
Post by: Manarq on June 05, 2013, 03:12:42 AM
A simple explanation is alright up to a certain point. The point of the equations is that they act as a proof for the explanation and provide a predictive element, without them it becomes a game of "my explanation makes more sense to me".
Title: Re: Space Flight
Post by: icanbeanything on June 05, 2013, 03:19:42 AM
I like to keep things simple. I'd rather someone explain a theory is simple terms rather than a thread full of equations for two reasons.

1. It is much more interesting to read simple explanations to theories.
2. People viewing the forum will not feel intimidated if they have a theory but can only explain it in simple terms and they will feel more inclined to join up and get involved, which as we all know can lead to many on here at least evaluating their thought process or even expanding their knowledge.
The more that take part in a topic, for or against or on the fence, it can bring up more questions and potential answers, which at the end of the day we are all trying to find aren't we.

I know that equations are part of science, so I don't need anyone to tell me this.


The problem is, when you read and think up simple explanations, you're using assumptions and philosophy to imagine how something happens, like this:
Quote
If you wanted to jump up, you know you cannot do it unless you produce a downward force to spring you up...so naturally you bend your knees and launch off of?....the floor, right?
The reason you spring up, is because your energy in your legs... (fuel)... meets resistance.. (floor)... and allows you to use that energy to propel you up.
You assume a rocket works similarly. You make assumptions based on your creative mind, and not theories.

This is the problem with simple explanations given without the understanding of the fundamental theories: you can get things wrong.
It may be harder to understand the theory, but without it, you can get things wrong. With the theory, you know you get things right.

This is how I know that my understanding of rocket theory confirms me that they work in space.

I did try explaining the theory as simply as I could, but as you can see, it's not that simple.
Title: Re: Space Flight
Post by: Scintific Method on June 05, 2013, 04:02:09 AM
Your theory is incorrect and I can swear to that 100%.
Rockets cannot work in a vacuum and I'm not 99.9% sure of this, I'm 100% sure of it.
If you are an honest person and a genuine scientific theorist, then you should know this and I'm being serious.

How can you possibly know with 100% certainty that you are correct when you have never even tested your ideas? It's all well and good to think that you're right, but until you actually test your ideas, they aren't worth a pinch of shit.

Just go and do the balloon in a vacuum chamber experiment. At least then you actually will know with 100% certainty.
Title: Re: Space Flight
Post by: Manarq on June 05, 2013, 04:40:57 AM
If you have an explosion in a vacuum do you agree that the particles and energy released by the explosion will expand in all directions?
Title: Re: Space Flight
Post by: DuckDodgers on June 05, 2013, 04:48:45 AM
A simple explanation is alright up to a certain point. The point of the equations is that they act as a proof for the explanation and provide a predictive element, without them it becomes a game of "my explanation makes more sense to me".
The simple explanation is usually the correct one, you know this...but this explanation I give, although simple, is counteracted by bull shit.
Not by you or others I might add...but by those that try to amaze us with their scientific misinformation.

I said that my goal is to smash the round rotating earth theory and this will go a long way into achieving that...because proving rockets do not work in a vacuum, proves that "all" missions and "all" probes/satellites/space stations/Hubble and "all" video and photographs of earth and space are fabricated.

If your goal is to smash the concept of RE, then this is a piss poor job at doing it.  Even your own force diagram of the balloon failed to show an force from the air surrounding the balloon acting upward on it to provide propulsion.
Title: Re: Space Flight
Post by: Scintific Method on June 05, 2013, 04:53:54 AM
Your theory is incorrect and I can swear to that 100%.
Rockets cannot work in a vacuum and I'm not 99.9% sure of this, I'm 100% sure of it.
If you are an honest person and a genuine scientific theorist, then you should know this and I'm being serious.

How can you possibly know with 100% certainty that you are correct when you have never even tested your ideas? It's all well and good to think that you're right, but until you actually test your ideas, they aren't worth a pinch of shit.

Just go and do the balloon in a vacuum chamber experiment. At least then you actually will know with 100% certainty.
The proof is right there for anyone to look at and read what I said.
You are simply duped by adhering to anything told to you by official explanations of it.

I don't trust what you say scepti, just like you don't trust anyone else. The big difference is, I can actually prove I'm right (and have done), whereas you haven't even done a single experiment to test your own ideas. If you had, you'd know you were wrong.

I mean no offense by any of that, I'm just trying to point out the flaws in your reasoning in order to assist you in improving it.
Title: Re: Space Flight
Post by: Manarq on June 05, 2013, 05:06:44 AM
If you have an explosion in a vacuum do you agree that the particles and energy released by the explosion will expand in all directions?
Yes.
Ok so if the particles released from the explosion hit a flat piece of metal nearby will the energy in those particles be transferred to the metal?
Title: Re: Space Flight
Post by: Scintific Method on June 05, 2013, 05:21:17 AM
You have just told lies right there saying you have done the experiment that proves I'm wrong.

No, I haven't lied. I have done experiments which prove the principles of rocket science, therefore I have done experiments that prove you wrong. Go do some experiments yourself, because thinking you know something means nothing until you actually prove it.
Title: Re: Space Flight
Post by: mathsman on June 05, 2013, 05:45:01 AM
You have just told lies right there saying you have done the experiment that proves I'm wrong.

No, I haven't lied. I have done experiments which prove the principles of rocket science, therefore I have done experiments that prove you wrong. Go do some experiments yourself, because thinking you know something means nothing until you actually prove it.
I'm calling you out as a liar, unless you explain to me exactly what you did that proved that rockets work in a vacuum.

The principle behind the movement of a rocket is the same as the principle behind the movement of deflating balloon, a garden hose releasing water under pressure, the 'kick' of a shotgun, the recoil of a cannon, Newton's cradle etc. It's called the conservation of momentum. No atmosphere is needed.
Title: Re: Space Flight
Post by: Manarq on June 05, 2013, 06:06:22 AM
If you have an explosion in a vacuum do you agree that the particles and energy released by the explosion will expand in all directions?
Yes.
Ok so if the particles released from the explosion hit a flat piece of metal nearby will the energy in those particles be transferred to the metal?
Yes.
So what will happen to the metal?
Title: Re: Space Flight
Post by: mathsman on June 05, 2013, 06:10:47 AM
You have just told lies right there saying you have done the experiment that proves I'm wrong.

No, I haven't lied. I have done experiments which prove the principles of rocket science, therefore I have done experiments that prove you wrong. Go do some experiments yourself, because thinking you know something means nothing until you actually prove it.
I'm calling you out as a liar, unless you explain to me exactly what you did that proved that rockets work in a vacuum.

The principle behind the movement of a rocket is the same as the principle behind the movement of deflating balloon, a garden hose releasing water under pressure, the 'kick' of a shotgun, the recoil of a cannon, Newton's cradle etc. It's called the conservation of momentum. No atmosphere is needed.
The principles are the same, it's just the environment that differs and how each separate thing is conducted.
It all boils down to how much force/thrust you use and against what.
The point is, they all need a solid base or a liquid or an atmosphere to all work.

No they don't. Let's use the shotgun example. The mass of the bullet multiplied by its speed will be the same as the mass of the gun multiplied by the speed of its recoil. The shoulder of the shooter is a much firmer base than the air in front of the gun so why does the shooter feel such a kick?

If the gun were to be fired under water the same equation would still hold:
speed of bullet x mass of bullet = speed of recoil x mass of gun. When you change the environment and the same equation holds one can only conclude that the environment has no effect on the principle. 
Title: Re: Space Flight
Post by: Scintific Method on June 05, 2013, 06:11:57 AM
Ok. So the exhaust is nothing, it's the fuel that's pushing the rocket up it's own arse type of thing.

Ok then tell me if this rocket would still fly and if it would, tell me why and if it won't, tell me why.


(http://img189.imageshack.us/img189/2706/blastoff.png) (http://imageshack.us/photo/my-images/189/blastoff.png/)



No, it won't fly, because the two thrust vectors are opposed to each other (one is pushing to the left, one is pushing to the right), thus cancelling each other out.
Title: Re: Space Flight
Post by: mathsman on June 05, 2013, 06:22:28 AM
You have just told lies right there saying you have done the experiment that proves I'm wrong.

No, I haven't lied. I have done experiments which prove the principles of rocket science, therefore I have done experiments that prove you wrong. Go do some experiments yourself, because thinking you know something means nothing until you actually prove it.
I'm calling you out as a liar, unless you explain to me exactly what you did that proved that rockets work in a vacuum.

The principle behind the movement of a rocket is the same as the principle behind the movement of deflating balloon, a garden hose releasing water under pressure, the 'kick' of a shotgun, the recoil of a cannon, Newton's cradle etc. It's called the conservation of momentum. No atmosphere is needed.
The principles are the same, it's just the environment that differs and how each separate thing is conducted.
It all boils down to how much force/thrust you use and against what.
The point is, they all need a solid base or a liquid or an atmosphere to all work.

No they don't. Let's use the shotgun example. The mass of the bullet multiplied by its speed will be the same as the mass of the gun multiplied by the speed of its recoil. The shoulder of the shooter is a much firmer base than the air in front of the gun so why does the shooter feel such a kick?

If the gun were to be fired under water the same equation would still hold:
speed of bullet x mass of bullet = speed of recoil x mass of gun. When you change the environment and the same equation holds one can only conclude that the environment has no effect on the principle.
You seriously and I mean seriously underestimate the strength of the atmosphere at sea level.

I'll buy it. What is the strength of the atmosphere at sea level? And what does that have to do with invalidating my example.
Title: Re: Space Flight
Post by: Manarq on June 05, 2013, 06:23:00 AM
If you have an explosion in a vacuum do you agree that the particles and energy released by the explosion will expand in all directions?
Yes.
Ok so if the particles released from the explosion hit a flat piece of metal nearby will the energy in those particles be transferred to the metal?
Yes.
So what will happen to the metal?
It would probably get pushed away if it was close enough.
And that is basically how a rocket works!
Title: Re: Space Flight
Post by: Scintific Method on June 05, 2013, 06:24:23 AM
Ok. So the exhaust is nothing, it's the fuel that's pushing the rocket up it's own arse type of thing.

Ok then tell me if this rocket would still fly and if it would, tell me why and if it won't, tell me why.


(http://img189.imageshack.us/img189/2706/blastoff.png) (http://imageshack.us/photo/my-images/189/blastoff.png/)



No, it won't fly, because the two thrust vectors are opposed to each other (one is pushing to the left, one is pushing to the right), thus cancelling each other out.
They're just two "exhaust" pipes into the atmosphere, you know, the one that makes no difference to a rockets propulsion.

I never mentioned the atmosphere, because it is not relevant to this diagram, or to the function of a rocket in general. Read my comment again.

Something else: try stepping off a small boat onto a jetty without mooring the boat or holding onto anything. Typically, the boat will be pushed out from under you and you will fall into the water. Why is this? Going by your logic, the water, being denser than air, should provide more resistance to the movement of the boat than the air does to the movement of your body, so the boat should stay put while you step onto the dock. Why doesn't it?
Title: Re: Space Flight
Post by: mathsman on June 05, 2013, 06:26:57 AM
If you have an explosion in a vacuum do you agree that the particles and energy released by the explosion will expand in all directions?
Yes.
Ok so if the particles released from the explosion hit a flat piece of metal nearby will the energy in those particles be transferred to the metal?
Yes.
So what will happen to the metal?
It would probably get pushed away if it was close enough.
And that is basically how a rocket works!

No it's not!
Title: Re: Space Flight
Post by: Manarq on June 05, 2013, 06:33:23 AM
If you have an explosion in a vacuum do you agree that the particles and energy released by the explosion will expand in all directions?
Yes.
Ok so if the particles released from the explosion hit a flat piece of metal nearby will the energy in those particles be transferred to the metal?
Yes.
So what will happen to the metal?
It would probably get pushed away if it was close enough.
And that is basically how a rocket works!

No it's not!
Yes it is, but a rocket engine encloses the explosion except for an exhaust.
Title: Re: Space Flight
Post by: Scintific Method on June 05, 2013, 06:44:16 AM
Ok. So the exhaust is nothing, it's the fuel that's pushing the rocket up it's own arse type of thing.

Ok then tell me if this rocket would still fly and if it would, tell me why and if it won't, tell me why.


(http://img189.imageshack.us/img189/2706/blastoff.png) (http://imageshack.us/photo/my-images/189/blastoff.png/)



No, it won't fly, because the two thrust vectors are opposed to each other (one is pushing to the left, one is pushing to the right), thus cancelling each other out.
They're just two "exhaust" pipes into the atmosphere, you know, the one that makes no difference to a rockets propulsion.

I never mentioned the atmosphere, because it is not relevant to this diagram, or to the function of a rocket in general. Read my comment again.

Something else: try stepping off a small boat onto a jetty without mooring the boat or holding onto anything. Typically, the boat will be pushed out from under you and you will fall into the water. Why is this? Going by your logic, the water, being denser than air, should provide more resistance to the movement of the boat than the air does to the movement of your body, so the boat should stay put while you step onto the dock. Why doesn't it?
stepping off a boat onto a jetty will only push the boat away once you create a force which comes from your imbalance, meaning one foot is on the boat and the other is about to hit the jetty, meaning you are leaning forward so naturally you kick your foot back against the boat, it's just action/reaction, so what.

What's this got to do with rockets working in a vacuum?

Action/reaction, Newton's 3rd law, which is one way to explain how rockets work. Picture the rocket as the boat, and the person stepping off as the exhaust gasses. The person moves one direction, the boat moves the other; the exhaust gasses move one direction, the rocket moves the other. Do you get it yet?
Title: Re: Space Flight
Post by: mathsman on June 05, 2013, 06:44:51 AM
If you have an explosion in a vacuum do you agree that the particles and energy released by the explosion will expand in all directions?
Yes.
Ok so if the particles released from the explosion hit a flat piece of metal nearby will the energy in those particles be transferred to the metal?
Yes.
So what will happen to the metal?
It would probably get pushed away if it was close enough.
And that is basically how a rocket works!

No it's not!
Yes it is, but a rocket engine encloses the explosion except for an exhaust.

No it isn't. Rockets, jet engines and any machine which uses expelled gases for propulsion uses the conservation of momentum. The product of the mass and the speed of the gases
in one direction is matched by the product of the mass of the object and its speed in the opposite direction. That's why the exhaust gases have to be at such high speeds so that the comparatively small mass of the exhausted gas is enough to provide the momentum for the much larger mass of the rocket. They don't push against anything, they don't transfer energy; the whole system of engine, rocket and exhausted gases conserve momentum.

Google 'the rocket equation'.
Title: Re: Space Flight
Post by: mathsman on June 05, 2013, 07:01:22 AM
If you have an explosion in a vacuum do you agree that the particles and energy released by the explosion will expand in all directions?
Yes.
Ok so if the particles released from the explosion hit a flat piece of metal nearby will the energy in those particles be transferred to the metal?
Yes.
So what will happen to the metal?
It would probably get pushed away if it was close enough.
And that is basically how a rocket works!

No it's not!
Yes it is, but a rocket engine encloses the explosion except for an exhaust.

No it isn't. Rockets, jet engines and any machine which uses expelled gases for propulsion uses the conservation of momentum. The product of the mass and the speed of the gases
in one direction is matched by the product of the mass of the object and its speed in the opposite direction. That's why the exhaust gases have to be at such high speeds so that the comparatively small mass of the exhausted gas is enough to provide the momentum for the much larger mass of the rocket. They don't push against anything, they don't transfer energy; the whole system of engine, rocket and exhausted gases conserve momentum.

Google 'the rocket equation'.
The way to get a rocket to lift off, is down to thrust as long as that thrust creates more force than the weight of the rocket and fuel the rocket will fly.
The reason it will fly, is because that thrust, is thrust against the atmosphere, which in turn pushes back to fill the void that the thrust opened up and so on and so on, until the rocket fuel is spent.

Utter bollocks.
Title: Re: Space Flight
Post by: Manarq on June 05, 2013, 07:06:10 AM
If you have an explosion in a vacuum do you agree that the particles and energy released by the explosion will expand in all directions?
Yes.
Ok so if the particles released from the explosion hit a flat piece of metal nearby will the energy in those particles be transferred to the metal?
Yes.
So what will happen to the metal?
It would probably get pushed away if it was close enough.
And that is basically how a rocket works!

No it's not!
Yes it is, but a rocket engine encloses the explosion except for an exhaust.

No it isn't. Rockets, jet engines and any machine which uses expelled gases for propulsion uses the conservation of momentum. The product of the mass and the speed of the gases
in one direction is matched by the product of the mass of the object and its speed in the opposite direction. That's why the exhaust gases have to be at such high speeds so that the comparatively small mass of the exhausted gas is enough to provide the momentum for the much larger mass of the rocket. They don't push against anything, they don't transfer energy; the whole system of engine, rocket and exhausted gases conserve momentum.

Google 'the rocket equation'.
You may also want to read http://en.wikipedia.org/wiki/Rocket_engine (http://en.wikipedia.org/wiki/Rocket_engine)
Title: Re: Space Flight
Post by: Rama Set on June 05, 2013, 07:17:05 AM
The simple way to understand how a rocket works in reality instead of bull shit science is to imagine this:

Think of a person (rocket) skipping slowly on the spot. We will call this, idling.
Ok, how do we get this skipper to lift off?

Firstly you needs lots of paving stones and a person strong enough to slip them under the skippers feet at speed.
We say to the skipper, "oi you... we need you to reach that ceiling in 20 seconds by skipping really fast."
If the skipper tell you to piss off, just tell them it's for an experiment and if he/she does not comply, threaten them with the bloke swinging the paving stones about as if they were polystyrene, will beat him/her up.

Anyway, let's assume that the person is sensible and wants to enjoy more years of skipping without crushed face/legs/arms etc and does comply.  ;D

Ok, so the skipper (rocket) starts to skip and on each skip, the bloke (atmosphere) puts a paving stone( atmospheric barrier) under the skippers (rockets) feet (thrust) as soon as they come off the floor and the faster the skipper (rocket) , skips, the faster the bloke (atmosphere) puts a paving stone(atmospheric barrier) under the feet (thrust), until it's happening so fast, it just looks like a blur and before you know it, the skipper has reached the ceiling before collapsing in a heap due to having no more energy.

And this my friends, is how rockets work in an atmosphere.

There is no bloke or paving stones in space, so poor skipper keeps skipping on the spot, expending all of his/her energy and gaining nothing other than fatigue (spent fuel)

Then why does a rocket work better in the air instead of the water?
Title: Re: Space Flight
Post by: mathsman on June 05, 2013, 07:22:27 AM
If you have an explosion in a vacuum do you agree that the particles and energy released by the explosion will expand in all directions?
Yes.
Ok so if the particles released from the explosion hit a flat piece of metal nearby will the energy in those particles be transferred to the metal?
Yes.
So what will happen to the metal?
It would probably get pushed away if it was close enough.
And that is basically how a rocket works!

No it's not!
Yes it is, but a rocket engine encloses the explosion except for an exhaust.

No it isn't. Rockets, jet engines and any machine which uses expelled gases for propulsion uses the conservation of momentum. The product of the mass and the speed of the gases
in one direction is matched by the product of the mass of the object and its speed in the opposite direction. That's why the exhaust gases have to be at such high speeds so that the comparatively small mass of the exhausted gas is enough to provide the momentum for the much larger mass of the rocket. They don't push against anything, they don't transfer energy; the whole system of engine, rocket and exhausted gases conserve momentum.

Google 'the rocket equation'.
You may also want to read http://en.wikipedia.org/wiki/Rocket_engine (http://en.wikipedia.org/wiki/Rocket_engine)

And you might want to read the opening few sentences fron the wikipedia entry on the Tsiolkovsky rocket equation:

'The Tsiolkovsky rocket equation, or ideal rocket equation, describes the motion of vehicles that follow the basic principle of a rocket: a device that can apply acceleration to itself (a thrust) by expelling part of its mass with high speed and move due to the conservation of momentum. '

My emphasis.

Title: Re: Space Flight
Post by: mathsman on June 05, 2013, 07:25:41 AM
If you have an explosion in a vacuum do you agree that the particles and energy released by the explosion will expand in all directions?
Yes.
Ok so if the particles released from the explosion hit a flat piece of metal nearby will the energy in those particles be transferred to the metal?
Yes.
So what will happen to the metal?
It would probably get pushed away if it was close enough.
And that is basically how a rocket works!

No it's not!
Yes it is, but a rocket engine encloses the explosion except for an exhaust.

No it isn't. Rockets, jet engines and any machine which uses expelled gases for propulsion uses the conservation of momentum. The product of the mass and the speed of the gases
in one direction is matched by the product of the mass of the object and its speed in the opposite direction. That's why the exhaust gases have to be at such high speeds so that the comparatively small mass of the exhausted gas is enough to provide the momentum for the much larger mass of the rocket. They don't push against anything, they don't transfer energy; the whole system of engine, rocket and exhausted gases conserve momentum.

Google 'the rocket equation'.
The way to get a rocket to lift off, is down to thrust as long as that thrust creates more force than the weight of the rocket and fuel the rocket will fly.
The reason it will fly, is because that thrust, is thrust against the atmosphere, which in turn pushes back to fill the void that the thrust opened up and so on and so on, until the rocket fuel is spent.

Utter bollocks.
I'm right and you have been misdirected and blinded by science.

I would much rather be blinded by science than be blinded by my own ignorance and prejudices. When I'm blinded by science I still have the capacity to reject the science. Your prejudices will blind you for the rest of your life.
Title: Re: Space Flight
Post by: Rama Set on June 05, 2013, 07:30:58 AM
If you have an explosion in a vacuum do you agree that the particles and energy released by the explosion will expand in all directions?
Yes.
Ok so if the particles released from the explosion hit a flat piece of metal nearby will the energy in those particles be transferred to the metal?
Yes.
So what will happen to the metal?
It would probably get pushed away if it was close enough.
And that is basically how a rocket works!

No it's not!
Yes it is, but a rocket engine encloses the explosion except for an exhaust.

No it isn't. Rockets, jet engines and any machine which uses expelled gases for propulsion uses the conservation of momentum. The product of the mass and the speed of the gases
in one direction is matched by the product of the mass of the object and its speed in the opposite direction. That's why the exhaust gases have to be at such high speeds so that the comparatively small mass of the exhausted gas is enough to provide the momentum for the much larger mass of the rocket. They don't push against anything, they don't transfer energy; the whole system of engine, rocket and exhausted gases conserve momentum.

Google 'the rocket equation'.
The way to get a rocket to lift off, is down to thrust as long as that thrust creates more force than the weight of the rocket and fuel the rocket will fly.
The reason it will fly, is because that thrust, is thrust against the atmosphere, which in turn pushes back to fill the void that the thrust opened up and so on and so on, until the rocket fuel is spent.

Utter bollocks.
I'm right and you have been misdirected and blinded by science.

I would much rather be blinded by science than be blinded by my own ignorance and prejudices. When I'm blinded by science I still have the capacity to reject the science. Your prejudices will blind you for the rest of your life.
At least I know I'm correct on this, so it tells you all you need to know about the space program.

You don't know this. That is a lie. You believe this. C'mon man. 
Title: Re: Space Flight
Post by: mathsman on June 05, 2013, 07:35:36 AM
If you have an explosion in a vacuum do you agree that the particles and energy released by the explosion will expand in all directions?
Yes.
Ok so if the particles released from the explosion hit a flat piece of metal nearby will the energy in those particles be transferred to the metal?
Yes.
So what will happen to the metal?
It would probably get pushed away if it was close enough.
And that is basically how a rocket works!

No it's not!
Yes it is, but a rocket engine encloses the explosion except for an exhaust.

No it isn't. Rockets, jet engines and any machine which uses expelled gases for propulsion uses the conservation of momentum. The product of the mass and the speed of the gases
in one direction is matched by the product of the mass of the object and its speed in the opposite direction. That's why the exhaust gases have to be at such high speeds so that the comparatively small mass of the exhausted gas is enough to provide the momentum for the much larger mass of the rocket. They don't push against anything, they don't transfer energy; the whole system of engine, rocket and exhausted gases conserve momentum.

Google 'the rocket equation'.
The way to get a rocket to lift off, is down to thrust as long as that thrust creates more force than the weight of the rocket and fuel the rocket will fly.
The reason it will fly, is because that thrust, is thrust against the atmosphere, which in turn pushes back to fill the void that the thrust opened up and so on and so on, until the rocket fuel is spent.

Utter bollocks.
I'm right and you have been misdirected and blinded by science.

I would much rather be blinded by science than be blinded by my own ignorance and prejudices. When I'm blinded by science I still have the capacity to reject the science. Your prejudices will blind you for the rest of your life.
At least I know I'm correct on this, so it tells you all you need to know about the space program.

No, it tells me all I need to know about you.
Title: Re: Space Flight
Post by: icanbeanything on June 05, 2013, 08:12:50 AM
Your theory is incorrect and I can swear to that 100%.
Rockets cannot work in a vacuum and I'm not 99.9% sure of this, I'm 100% sure of it.
If you are an honest person and a genuine scientific theorist, then you should know this and I'm being serious.

I am a genuine physicist.

You are 100% sure that a rocket doesn't work in a vacuum, because you don't want it to work in a vacuum.

If you fail to understand the physics behind it, at least trust me on it, ok? They work.
Title: Re: Space Flight
Post by: Manarq on June 05, 2013, 08:36:27 AM

You may also want to read http://en.wikipedia.org/wiki/Rocket_engine (http://en.wikipedia.org/wiki/Rocket_engine)

And you might want to read the opening few sentences fron the wikipedia entry on the Tsiolkovsky rocket equation:

'The Tsiolkovsky rocket equation, or ideal rocket equation, describes the motion of vehicles that follow the basic principle of a rocket: a device that can apply acceleration to itself (a thrust) by expelling part of its mass with high speed and move due to the conservation of momentum. '

My emphasis.

1: I had just about got Sceptimatic to accept that expanding gases in a vacuum can create motion, thanks for derailing that.
2: By all means why don't you explain how gases coming out of the back of a rocket can create motion in the opposite direction without exerting any force on the rocket.
Title: Re: Space Flight
Post by: icanbeanything on June 05, 2013, 08:38:40 AM
Your theory is incorrect and I can swear to that 100%.
Rockets cannot work in a vacuum and I'm not 99.9% sure of this, I'm 100% sure of it.
If you are an honest person and a genuine scientific theorist, then you should know this and I'm being serious.

I am a genuine physicist.

You are 100% sure that a rocket doesn't work in a vacuum, because you don't want it to work in a vacuum.

If you fail to understand the physics behind it, at least trust me on it, ok? They work.
No offence but I don't care if you are god himself. I'm telling you that rockets do not and never will work in a vacuum, unless they come up with some way to overcome propulsion in a void.

You are under the impression that we are more intelligent than we are as a race.
We can solve many of our earth problems but we know jack shit about space in terms of going into it with anything but an eye piece from earth, as in, a telescope and even then we can only just see a tiny portion of it, not the bloody Christmas tree light effect of a so called cosmos.

I promise you and I stand by this. I promise you that rockets do not work in a vacuum.

Relax, like I said before in my laser experiment post, I've done experiments myself with rocket propulsion in a vacuum.
I really hope I can take you on a rocket ride some day. Oh my, I just made a music reference... gosh.
Title: Re: Space Flight
Post by: icanbeanything on June 05, 2013, 08:42:06 AM
icanbeanything:
If you do manage to take me on a rocket ride, it certainly won't be into space.

Pity, 'cause that's what I meant.
Title: Re: Space Flight
Post by: Fizzy Logic on June 05, 2013, 08:53:32 AM
Still haven't done any research?
Title: Re: Space Flight
Post by: icanbeanything on June 05, 2013, 09:07:58 AM
icanbeanything:
If you do manage to take me on a rocket ride, it certainly won't be into space.

Pity, 'cause that's what I meant.
Well, forget your dream of going into space. I'll save you the heartache of finding out that you never will.
On that understanding, it may be wise for you not to actually go into any rocket, because once it's fuel is spent so many miles up, you will be coming back down extremely fast, still stuck inside it and you know what the end result of that is.

I probably never will, but not because it isn't possible.
And from my experience, the end result of anything like that is a parachute. I know a lot about those too, I've even done some skydiving.

Quote
Don't expend too much energy guessing what I do, concentrate on helping you fellow roundies out, which means, try and put a case forward for rocket propulsion in space.
Nobody can do it yet, maybe you can stump me.

We've all done that already. I even said I performed experiments that confirmed to my eyes that rockets work in a vacuum. But you'll never believe me on that, unless you do it yourself. And I know why you don't want to do it... Because you don't want to have even the slightest chance of finding out you were wrong.
Title: Re: Space Flight
Post by: markjo on June 05, 2013, 09:10:02 AM
I know that I'll probably regret this, but here goes.

Sceptimatic, I think understand your objection to rockets working in a vacuum.  You claim that the vacuum of space will suck out all of the rocket's exhaust gasses before they can do any work.  Well, that's true, up to a point.  Here is a simple experiment that you can try at home. 

Let's look at a typical kitchen funnel.  It has a wide end where stuff goes in and a skinny end where stuff comes out, right?  Well, let us take that funnel to the kitchen sink and start pouring water into the funnel.  If we start the water slowly, you will notice that it drains out of the skinny end just as fast as it pours into the big end.  This is just like the vacuum of space sucking the exhaust gasses out of a rocket engine that is only burning a little bit of fuel and oxidizer at a time. 

Now let us turn up the water at the sink. You will notice that after a certain point, the water going into the big end faster than the water can come out of the skinny end.  In the same way, if you burn enough fuel and oxidizer fast enough, the exhaust gasses build up in the rocket's combustion chamber faster than the vacuum of space can suck them out of the little hole in the combustion chamber. 

Basically, it all comes down to pressure.  In the same way that pressure can build up in a funnel or a water hose with a nozzle, gas pressure can build up in a rocket engine's combustion chamber. 

I realize that this is probably a waste of time, but I am an eternal optimist and hold out some faint hope that this funnel analogy will help you understand rockets a little better.
Title: Re: Space Flight
Post by: icanbeanything on June 05, 2013, 09:14:31 AM
I wrote a lot about pressure differential to him a few pages back, but I never got a response regarding it. I assume he just disregarded it, if he even read it. You just can't trust a scientist...
Title: Re: Space Flight
Post by: icanbeanything on June 05, 2013, 09:34:48 AM
I wrote a lot about pressure differential to him a few pages back, but I never got a response regarding it. I assume he just disregarded it, if he even read it. You just can't trust a scientist...
Oh, scientists can be trusted , just not trusted to always tell it how it should be, which may or may not be their fault, as my placebo post illustrates.

You see, it's not only students than can be duped...those that teach them were once students who were taught what they, themselves were taught and so on  and so on.

How is it duping when I'm doing my own experiment with propulsion in a vacuum? It's right in front of me, I'm doing everything. And you can, too:

Quote
1. I'm never going to see a rocket go into space.
2. Rockets do not work in a vacuum.

1. You've seen rockets go into space, you just consider them fake.
2. Now this is something you can see yourself much easier, since a vacuum is achievable right here. Which is why I suggested the balloon experiment. You could, actually, see for yourself how a rocket works in a vacuum, right in front of you.


Title: Re: Space Flight
Post by: icanbeanything on June 05, 2013, 09:56:28 AM
A bigger vacuum chamber, which you can find plenty of, can have a volume of around a cubic meter. The gas in a pocket-sized, uninflated balloon is no more than 50 mL. That gas, if it comes out of the balloon and fills the chamber, will still leave it in a near-vacuum state (I won't post calculations). But nevertheless, you'll be seeing the balloon fly first, before its gas left it.

And what I did, I have said already in a post but I guess you didn't consider it much, was laser propulsion. High powered laser in a vacuum, attempt to measure the thrust it produces. Not unile a rocket. If a laser rocket works in a vacuum, you can be sure a liquid fuel rocket works too.

As a sidenote, again, I already said that outer space doesn't have zero pressure. There is some, though not much. We can create much, much more perfect vacuum in a vacuum chamber.
Title: Re: Space Flight
Post by: Rama Set on June 05, 2013, 09:57:04 AM
How is it duping when I'm doing my own experiment with propulsion in a vacuum? It's right in front of me, I'm doing everything. And you can, too:
Quote from: sceptimatic
So what are you doing exactly that proves rockets work in a vacuum. Just explain it to me.

This.

One example would be measuring the thrust generated by a special laser, testing for laser propulsion. Experiment done in a vacuum. You turn on the laser, the beam comes out one end, and it pushes the device the other way, with a very small force that I had to measure.
Title: Re: Space Flight
Post by: markjo on June 05, 2013, 10:14:18 AM
I know that I'll probably regret this, but here goes.

Sceptimatic, I think understand your objection to rockets working in a vacuum.  You claim that the vacuum of space will suck out all of the rocket's exhaust gasses before they can do any work.  Well, that's true, up to a point.  Here is a simple experiment that you can try at home. 

Let's look at a typical kitchen funnel.  It has a wide end where stuff goes in and a skinny end where stuff comes out, right?  Well, let us take that funnel to the kitchen sink and start pouring water into the funnel.  If we start the water slowly, you will notice that it drains out of the skinny end just as fast as it pours into the big end.  This is just like the vacuum of space sucking the exhaust gasses out of a rocket engine that is only burning a little bit of fuel and oxidizer at a time. 

Now let us turn up the water at the sink. You will notice that after a certain point, the water going into the big end faster than the water can come out of the skinny end.  In the same way, if you burn enough fuel and oxidizer fast enough, the exhaust gasses build up in the rocket's combustion chamber faster than the vacuum of space can suck them out of the little hole in the combustion chamber. 

Basically, it all comes down to pressure.  In the same way that pressure can build up in a funnel or a water hose with a nozzle, gas pressure can build up in a rocket engine's combustion chamber. 

I realize that this is probably a waste of time, but I am an eternal optimist and hold out some faint hope that this funnel analogy will help you understand rockets a little better.
With all due respect Marko, you have your fuel backside first...can you see what I mean?
No, I don't.  Please explain.  Also, please understand that there is a difference between fuel and exhaust gasses.  The fuel doesn't do the work, the expanding gasses created when the fuel burns does the work.

Quote
Also, ponder this.
The fuel in the combustion chamber has no time to expand, because for it to combust, it must have an outlet.... you know, just like a car engine, where fuel is sprayed into the piston area and ignites, pushing the piston down, aided by air coming into it, which is a key point here, because the minute...or should I say the millisecond that fuel and air exposes itself to the vacuum, that's it, game over.
Okay, so you don't understand how internal combustion engines work either.  Got it.

In a 4 stroke internal combustion engine, both the intake and exhaust valves are closed when the spark plug ignites the fuel/air mix in the combustion chamber (does the term "compression ratio" mean anything to you?).  There is no air coming in to aid in pushing the piston down.  In fact, the spark plug typically fires just before the piston hits top dead center because it take some time for the fuel/air mix to burn and generate the exhaust gasses to push the piston down.

In the same way, it takes time for the fuel/oxidizer mix in a rocket's combustion chamber to burn and it takes time for the vacuum of space to suck those gasses out.  It's just a matter of being able to burn the fuel/oxidizer mix and generate gas pressure faster than the vacuum of space can suck those gasses out so that those gasses are actually under tremendous pressure as they leave the combustion chamber. 
Title: Re: Space Flight
Post by: icanbeanything on June 05, 2013, 10:18:29 AM
If you don;t mind can you draw me a little diagram of what you actually did with this laser as I am seriously stuck here with this. Basically I cannot picture what you mean.

I won't go into the details because it gets complicated fast, but the basic idea to picture is this:

You take a laser, you turn it on, and you have a device that measures how hard the laser's pushing the opposite way while it's on. It doesn't really need to be in a vacuum, but I had to put in in one because the amount of force generated is so minuscule that any air movement would throw off the measurement. Perfectly still air is impossible to do even in a lab. A vacuum is easy.

So the basic picture is a laser turned on, and put on a scale that measures how hard it is pushing on it. Like a very weak rocket, get it?

Quote
the minute...or should I say the millisecond that fuel and air exposes itself to the vacuum, that's it, game over.

A millisecond is an eternity in engineering applications. I just had a visit today to check out a pulse laser that works in 100 femtosecond pulses with a 60 MHz frequency. So, each pulse lasted 100 femtoseconds and was separated by 12 nanoseconds from the previous pulse.

Imagine that pulse lasted one second. In that case, the time between the pulses would've been a whole year. Yet, 60 million of those pulses were happening every second. And it's all done by electronics that synchronize everything.

So really, a millisecond is an eternity in such applications. Fuel is much slower than light, it's really not hard to ignite even when the outlet is a vacuum.
Title: Re: Space Flight
Post by: Shmeggley on June 05, 2013, 10:25:13 AM
Pardon me if this has been brought up before, I tried to go back and check but this thread is getting longer by the minute.

Anyway, Sceptimatic, there's a problem I see with how your rocket theory works. You are claiming that the rocket exhaust needs air or something to push against, correct?

If this is true, how is force transferred to the rocket at all? The particles have already exited the rocket nozzle, they hit the air, or the ground, etc, then what? How does a particle that's no longer in contact with the rocket in any way somehow push the rocket along?
Title: Re: Space Flight
Post by: DuckDodgers on June 05, 2013, 10:32:24 AM
(http://)

There you go,  rocket engine in a vacuum.
Title: Re: Space Flight
Post by: icanbeanything on June 05, 2013, 10:57:39 AM
(http://)

There you go,  rocket engine in a vacuum.

Posted just that a few pages back... he didn't believe there was a vacuum there.
Title: Re: Space Flight
Post by: DuckDodgers on June 05, 2013, 11:00:17 AM
(http://)

There you go,  rocket engine in a vacuum.

Posted just that a few pages back... he didn't believe there was a vacuum there.

Oh well,  worth a shot to do his inane drivel.
Title: Re: Space Flight
Post by: Rama Set on June 05, 2013, 11:02:01 AM
(http://)

There you go,  rocket engine in a vacuum.

Posted just that a few pages back... he didn't believe there was a vacuum there.

Of course not, that would be a disaster for him.  Notice how anyone who explains that they have first hand experience countermanding what he describes is either a liar, or he forgets that they have spoken. Its astounding.
Title: Re: Space Flight
Post by: icanbeanything on June 05, 2013, 11:06:26 AM
(http://)

There you go,  rocket engine in a vacuum.

Posted just that a few pages back... he didn't believe there was a vacuum there.

Of course not, that would be a disaster for him.  Notice how anyone who explains that they have first hand experience countermanding what he describes is either a liar, or he forgets that they have spoken. Its astounding.

No, it's not. I kind of understand it. He simply doesn't want to risk even the slightest possibility of somehow finding out he's wrong.

You see, you would think it would be pretty cool for Scepti to re-convert, but I don't think it'd feel good for him.
Title: Re: Space Flight
Post by: icanbeanything on June 05, 2013, 12:00:09 PM
Scepti, it's just a laser. You turn on the laser, and because light is coming out one end, it's pushing the laser the other end. This happens in every laser, it's just that it's a very very very weak effect.

I used a pretty powerful laser in a vacuum chamber so I could measure the force it pushed with.
Title: Re: Space Flight
Post by: icanbeanything on June 05, 2013, 12:04:57 PM
I can't re-convert to a pack of lies, can I.
Flat earth is the way forward and it's you and others that need to re-evaluate to be fair.

I didn't say I expected you to, nor did I say that you want to. I simply said that if it happened, it probably wouldn't be a fun experience to you.
Title: Re: Space Flight
Post by: icanbeanything on June 05, 2013, 12:06:03 PM
Scepti, it's just a laser. You turn on the laser, and because light is coming out one end, it's pushing the laser the other end. This happens in every laser, it's just that it's a very very very weak effect.

I used a pretty powerful laser in a vacuum chamber so I could measure the force it pushed with.
My eye rolling was for your feeble attempt at trying to prove a rocket works in a vacuum with a bloody laser man.lol

The laser works like a rocket. Something is coming out one end, and it's pushing the object the other way. For the laser it's light. I did the experiment, in a vacuum.

You know, for someone so opposed to appeals to ridicule, you really like to appeal to ridicule yourself.
Title: Re: Space Flight
Post by: markjo on June 05, 2013, 12:22:16 PM
I know that I'll probably regret this, but here goes.

Sceptimatic, I think understand your objection to rockets working in a vacuum.  You claim that the vacuum of space will suck out all of the rocket's exhaust gasses before they can do any work.  Well, that's true, up to a point.  Here is a simple experiment that you can try at home. 

Let's look at a typical kitchen funnel.  It has a wide end where stuff goes in and a skinny end where stuff comes out, right?  Well, let us take that funnel to the kitchen sink and start pouring water into the funnel.  If we start the water slowly, you will notice that it drains out of the skinny end just as fast as it pours into the big end.  This is just like the vacuum of space sucking the exhaust gasses out of a rocket engine that is only burning a little bit of fuel and oxidizer at a time. 

Now let us turn up the water at the sink. You will notice that after a certain point, the water going into the big end faster than the water can come out of the skinny end.  In the same way, if you burn enough fuel and oxidizer fast enough, the exhaust gasses build up in the rocket's combustion chamber faster than the vacuum of space can suck them out of the little hole in the combustion chamber. 

Basically, it all comes down to pressure.  In the same way that pressure can build up in a funnel or a water hose with a nozzle, gas pressure can build up in a rocket engine's combustion chamber. 

I realize that this is probably a waste of time, but I am an eternal optimist and hold out some faint hope that this funnel analogy will help you understand rockets a little better.
With all due respect Marko, you have your fuel backside first...can you see what I mean?
No, I don't.  Please explain.  Also, please understand that there is a difference between fuel and exhaust gasses.  The fuel doesn't do the work, the expanding gasses created when the fuel burns does the work.
Yes. They expand into the atmosphere.
The atmosphere is considered to extend several thousand miles into space.  So what's the difference between the 1000 psi gasses expanding into 14 psi atmosphere near sea level or 1000 psi gasses expanding into a .0000001 psi near vacuum 100 miles up?

Quote
Quote
Quote
Also, ponder this.
The fuel in the combustion chamber has no time to expand, because for it to combust, it must have an outlet.... you know, just like a car engine, where fuel is sprayed into the piston area and ignites, pushing the piston down, aided by air coming into it, which is a key point here, because the minute...or should I say the millisecond that fuel and air exposes itself to the vacuum, that's it, game over.
Okay, so you don't understand how internal combustion engines work either.  Got it.
Misconstruing what I said, I see. I know it's a closed unit on combustion but it takes "air" and "fuel" into it , is what I meant.
I'm not psychic.  Say what you mean and mean what you say.

Rocket engines take in air and fuel just like internal combustion engines.  The main difference is that rockets burn the fuel/air mix continuously rather than in a 4 stage cycle.
Title: Re: Space Flight
Post by: mathsman on June 05, 2013, 12:47:04 PM

You may also want to read http://en.wikipedia.org/wiki/Rocket_engine (http://en.wikipedia.org/wiki/Rocket_engine)

And you might want to read the opening few sentences fron the wikipedia entry on the Tsiolkovsky rocket equation:

'The Tsiolkovsky rocket equation, or ideal rocket equation, describes the motion of vehicles that follow the basic principle of a rocket: a device that can apply acceleration to itself (a thrust) by expelling part of its mass with high speed and move due to the conservation of momentum. '

My emphasis.

1: I had just about got Sceptimatic to accept that expanding gases in a vacuum can create motion, thanks for derailing that.
2: By all means why don't you explain how gases coming out of the back of a rocket can create motion in the opposite direction without exerting any force on the rocket.

How difficult is it to understand conservation of momentum? The gases expelled have a certain mass and are expelled at high speed. This means they have a momentum. The rocket and its remaining fuel also have a mass and must move at a speed in the opposite direction so that they have a momentum equal in magnitude but opposite in direction and therefore opposite in sign to the momentum of the gases. This maintains the total momentum of the system.
Mass of gases x speed of gases = mass of rocket x speed of rocket. This is how rockets work in a vacuum.
By all means don't bother to learn about conservation of momentum.
Title: Re: Space Flight
Post by: Manarq on June 05, 2013, 02:49:09 PM

You may also want to read http://en.wikipedia.org/wiki/Rocket_engine (http://en.wikipedia.org/wiki/Rocket_engine)

And you might want to read the opening few sentences fron the wikipedia entry on the Tsiolkovsky rocket equation:

'The Tsiolkovsky rocket equation, or ideal rocket equation, describes the motion of vehicles that follow the basic principle of a rocket: a device that can apply acceleration to itself (a thrust) by expelling part of its mass with high speed and move due to the conservation of momentum. '

My emphasis.

1: I had just about got Sceptimatic to accept that expanding gases in a vacuum can create motion, thanks for derailing that.
2: By all means why don't you explain how gases coming out of the back of a rocket can create motion in the opposite direction without exerting any force on the rocket.

How difficult is it to understand conservation of momentum? The gases expelled have a certain mass and are expelled at high speed. This means they have a momentum. The rocket and its remaining fuel also have a mass and must move at a speed in the opposite direction so that they have a momentum equal in magnitude but opposite in direction and therefore opposite in sign to the momentum of the gases. This maintains the total momentum of the system.
Mass of gases x speed of gases = mass of rocket x speed of rocket. This is how rockets work in a vacuum.
By all means don't bother to learn about conservation of momentum.
How does a rocket force the gases out at high speed?

http://exploration.grc.nasa.gov/education/rocket/TRCRocket/rocket_principles.html (http://exploration.grc.nasa.gov/education/rocket/TRCRocket/rocket_principles.html)
Title: Re: Space Flight
Post by: Fizzy Logic on June 05, 2013, 03:43:55 PM
Do you sometimes read the links you are given or are you too dumb?

Your basic understanding of basic physics is close to nil. Please read, study, think!
Title: Re: Space Flight
Post by: Scintific Method on June 05, 2013, 05:26:50 PM
Something else: try stepping off a small boat onto a jetty without mooring the boat or holding onto anything. Typically, the boat will be pushed out from under you and you will fall into the water. Why is this? Going by your logic, the water, being denser than air, should provide more resistance to the movement of the boat than the air does to the movement of your body, so the boat should stay put while you step onto the dock. Why doesn't it?
stepping off a boat onto a jetty will only push the boat away once you create a force which comes from your imbalance, meaning one foot is on the boat and the other is about to hit the jetty, meaning you are leaning forward so naturally you kick your foot back against the boat, it's just action/reaction, so what.

What's this got to do with rockets working in a vacuum?

Action/reaction, Newton's 3rd law, which is one way to explain how rockets work. Picture the rocket as the boat, and the person stepping off as the exhaust gasses. The person moves one direction, the boat moves the other; the exhaust gasses move one direction, the rocket moves the other. Do you get it yet?
Wait just one cotton picking minute here.

You are explaining, now, how rockets actually do work...why have you changed your mind?

As the person steps off the boat, their foot pushes back on the boat. This does two things: it pushes the person forward toward the jetty, and it pushes the boat back away from the jetty. As you said, action/reaction. As a scientist would say, Newton's 3rd law (or conservation of momentum, since the two are very closely related).

A rocket follows the same principle. In order for the exhaust gasses to move away from the rocket, they must first push on the rocket, just like the person has to push on the boat with their foot in order to move toward the jetty. The direction of this push is determined by the exhaust nozzle, as the nozzle determines which way the gasses go when they leave.

To put this back in the context of the person on the boat, when they step off forward, the boat doesn't go left (or right), it goes straight back. Your rocket diagram would be like two people stepping off opposite sides of the boat at exactly the same time.

Please take note: at no point here have I said that the person (or the exhaust gasses) are pushing on anything else other than the boat (or rocket).

Does this help you at all?
Title: Re: Space Flight
Post by: markjo on June 05, 2013, 06:55:06 PM
A rocket burns it's fuel...that's all it does and that burned fuel is pushed against the atmosphere, expanded into it and the atmosphere fights back. It's as simple as that.
Actually, there is a little more to it than that.  A rocket burns fuel inside a combustion chamber.  When that fuel burns, it creates gasses that expand quite vigorously.  As those gasses expand, they are looking for some place to go.  Those gasses find a small hole in the combustion chamber where they find a vacuum on the other side that wants to suck out those gasses.  But the hole is so small and the rocket is burning so much fuel so fast that the gasses expand so fast the vacuum can't suck the gasses out fast enough.  So, what do you think happens?  That's right, since gasses are expanding faster than the vacuum of space can suck them out, pressure builds up within the combustion chamber.  This pressure inside the combustion chamber is the key element to making rocket engines work in a vacuum.  If you can't accept this simple principle, then there is no use in continuing this discussion.
Title: Re: Space Flight
Post by: hoppy on June 05, 2013, 07:36:56 PM
Here is someone else who seems to have thought the whole "rockets can't work in a vacuum" through a little better than Sceptimatic.  He's still wrong, but at least he tries to give specific reasons.
http://cluesforum.info/viewtopic.php?f=23&t=1632&sid=859ccbe6e2bec4c0fa4419addac7bd92 (http://cluesforum.info/viewtopic.php?f=23&t=1632&sid=859ccbe6e2bec4c0fa4419addac7bd92)
Excellent post markjo. I tried looking for info about rockets not working in space and found nothing. This is very interesting reading.



At this point we have a rocket with high-pressure gas generated from liquid fuel that can release the gas into a vacuum but has no way to produce a force while doing so. As soon as the nozzle is opened the gasses escape without doing any work. Therefore the 3rd Law is rendered useless.

As it turns out NASA does not fall into the 3rd Law trap (nor does it go around correcting all the sites who do) instead claiming that thrust of a space rocket is generated using what I call The Wrong Formula, an egregious farce of Newton's 2nd law which I will address in a later next post.

To recap: Newton’s 3rd Law, the number one response on the Internet to how a rocket generates thrust in space, is invalid in this context. NASA itself avoids using Newton’s 3rd Law as the reason why their rockets work so well in space choosing to use Newton’s 2nd Law instead. I will show in a later post why NASA’s use the 2nd Law is equally invalid and in fact a hideous misrepresentation of the laws of the laws of physics that would give a freshman college student a failing grade yet earns NASA an "A" thanks to its pretty pictures, dramatic story lines, and gutsy champions, the astronauts.
Title: Re: Space Flight
Post by: mathsman on June 06, 2013, 12:09:47 AM

You may also want to read http://en.wikipedia.org/wiki/Rocket_engine (http://en.wikipedia.org/wiki/Rocket_engine)

And you might want to read the opening few sentences fron the wikipedia entry on the Tsiolkovsky rocket equation:

'The Tsiolkovsky rocket equation, or ideal rocket equation, describes the motion of vehicles that follow the basic principle of a rocket: a device that can apply acceleration to itself (a thrust) by expelling part of its mass with high speed and move due to the conservation of momentum. '

My emphasis.

1: I had just about got Sceptimatic to accept that expanding gases in a vacuum can create motion, thanks for derailing that.
2: By all means why don't you explain how gases coming out of the back of a rocket can create motion in the opposite direction without exerting any force on the rocket.

How difficult is it to understand conservation of momentum? The gases expelled have a certain mass and are expelled at high speed. This means they have a momentum. The rocket and its remaining fuel also have a mass and must move at a speed in the opposite direction so that they have a momentum equal in magnitude but opposite in direction and therefore opposite in sign to the momentum of the gases. This maintains the total momentum of the system.
Mass of gases x speed of gases = mass of rocket x speed of rocket. This is how rockets work in a vacuum.
By all means don't bother to learn about conservation of momentum.
How does a rocket force the gases out at high speed?

http://exploration.grc.nasa.gov/education/rocket/TRCRocket/rocket_principles.html (http://exploration.grc.nasa.gov/education/rocket/TRCRocket/rocket_principles.html)

Sceptimatic made the claim that rockets can't work in a vacuum because they have nothing to push against. I patiently explained that rockets don't need anything to push against. The means by which the gases are expelled does not change the principle of the conservation of momentum. It's a bit like arguing that the laws of physics change because one car is powered by petrol and another is powered by diesel. You are looking at the engineering I'm looking at the physics.
Title: Re: Space Flight
Post by: mathsman on June 06, 2013, 03:34:14 AM
Now because a rocket burns fuel with massive force that creates huge thrust..this is where the wide rocket nozzle comes in to move it's mass...because that rocket nozzle allows the burning gases to expand into a wide atmospheric area, meaning the atmosphere must create an equal force to push back against it, so basically your rocket is pushed up by the gases fighting against each other.

So now you know why rockets need atmosphere, you should have no problem understanding that rockets in space is an impossibility.

That's not how rockets work. They do not need an atmosphere. The rocket and its expelled fuel is a conservative system which maintains its momentum.

Don't worry this is the last time I will nag you on this. I wouldn't mind asking a favour though: Do you know of any properly qualified engineer who agrees with you and point me in his direction?
Title: Re: Space Flight
Post by: Scintific Method on June 06, 2013, 04:25:33 AM
Next time you're in your garden with the garden hose , you will be watering the garden and seeing a stream of water just coming out of the end of the hose.
No problem right?
Well that water coming out of the hose, is your rocket and fuel. The hose is your rocket and the water is the fuel coming out of your rocket.
We need to make that hose move though, so what can we do?
Well because the water is only coming out in a steady stream, it has little thrust so we need to create a barrier to make that hose move.

Whoa buddy, hang on there! You go on to say that putting your hand in front of the hose will increase the force pushing it back, but have you actually tried this? I know that turning up the flow will definitely increase the thrust, but I have never experienced an increase in thrust by putting my hand in front of the nozzle.

This would be worth setting up as an experiment, arranging the hose so that thrust with and without a hand in the way of the flow of water could be compared. Seeing as you brought it up, how would you like to do the experiment and let us know what you find?
Title: Re: Space Flight
Post by: icanbeanything on June 06, 2013, 04:38:19 AM
This would be worth setting up as an experiment, arranging the hose so that thrust with and without a hand in the way of the flow of water could be compared. Seeing as you brought it up, how would you like to do the experiment and let us know what you find?

It's easy enough, but you're asking Scepti to do an experiment...
Title: Re: Space Flight
Post by: icanbeanything on June 06, 2013, 04:47:07 AM
This would be worth setting up as an experiment, arranging the hose so that thrust with and without a hand in the way of the flow of water could be compared. Seeing as you brought it up, how would you like to do the experiment and let us know what you find?

It's easy enough, but you're asking Scepti to do an experiment...
I've done it and so have you and most others, so what's difficult about it.

You've actually checked that putting your hand in the jet of the hose actually pushes the hose more than if your hand wasn't there?
Title: Re: Space Flight
Post by: icanbeanything on June 06, 2013, 04:48:09 AM
Think of riot police shooting a water cannon at a person.
The water cannon is the rocket and the water is the fuel and the rioter is the atmosphere.
The water gets aimed at the rioter but he won't back down and tries to stay upright and push against the water coming from the cannon right?

Now imagine that the police say, ok lads we need more thrust to knock this man back, so they turn up the water pressure...but as they do so, they are now met with the rioters accomplice, who stands behind him, so they turn up the pressure again, only to see another accomplice behind the second man and so on and so on and it becomes a fight until someone gives up, which would be the police as they run out of water.

Can you see how the atmosphere works against the rockets gases now?

That's all fine, except the presence of rioters does not push the water cannon the other way. So there's no rocket action there.
Title: Re: Space Flight
Post by: Scintific Method on June 06, 2013, 04:49:22 AM
Next time you're in your garden with the garden hose , you will be watering the garden and seeing a stream of water just coming out of the end of the hose.
No problem right?
Well that water coming out of the hose, is your rocket and fuel. The hose is your rocket and the water is the fuel coming out of your rocket.
We need to make that hose move though, so what can we do?
Well because the water is only coming out in a steady stream, it has little thrust so we need to create a barrier to make that hose move.
[/quote

Whoa buddy, hang on there! You go on to say that putting your hand in front of the hose will increase the force pushing it back, but have you actually tried this?
Quote
I would imagine everyone who's used a hose has tried this but it will have had no meaning to just about all of them.
I know that turning up the flow will definitely increase the thrust, but I have never experienced an increase in thrust by putting my hand in front of the nozzle.
Quote
I never implied you were. I stated that your hand is a barrier and the closer you put your hand to the hose water coming out of the hose, then at some stage, the closer your hand gets, it will create a more stronger barrier against the water coming out and eventually creating a force against that water, so it creates a small force on your hand and also on the water, in which case, the hose is forced back the closer your hand gets. go and try it...I have.

This would be worth setting up as an experiment, arranging the hose so that thrust with and without a hand in the way of the flow of water could be compared. Seeing as you brought it up, how would you like to do the experiment and let us know what you find?

Yeah, I still get a far more noticeable increase in thrust by turning up the pressure. To feel an increase by putting my hand in the way, I have to almost block the hose off with that hand to feel any difference.
Title: Re: Space Flight
Post by: icanbeanything on June 06, 2013, 04:54:32 AM
Think of riot police shooting a water cannon at a person.
The water cannon is the rocket and the water is the fuel and the rioter is the atmosphere.
The water gets aimed at the rioter but he won't back down and tries to stay upright and push against the water coming from the cannon right?

Now imagine that the police say, ok lads we need more thrust to knock this man back, so they turn up the water pressure...but as they do so, they are now met with the rioters accomplice, who stands behind him, so they turn up the pressure again, only to see another accomplice behind the second man and so on and so on and it becomes a fight until someone gives up, which would be the police as they run out of water.

Can you see how the atmosphere works against the rockets gases now?

That's all fine, except the presence of rioters does not push the water cannon the other way. So there's no rocket action there.
Of course there's isn't, because there's not enough pressure to overturn the riot vehicle with the water cannon but if there was enough pressure and they kept turning it up and each time they did, it was met with an equally opposite mass of people, then eventually that pressure would, indeed over turn the vehicle.

Aha. So it's the pressure of the water that is pushing the water cannon the other way, isn't it? So, whether the rioters are there or aren't, it doesn't matter, because if you turn the pressure high enough even without any rioters present, the vehicle will turn over.

So, you only need big enough pressure, you don't need the presence of an atmosphere.
Title: Re: Space Flight
Post by: icanbeanything on June 06, 2013, 05:02:42 AM
I've "grasped" rocket science well enough four years ago. We can exchange allegories all day, but philosophy is not what makes the world work.
Title: Re: Space Flight
Post by: Scintific Method on June 06, 2013, 05:08:01 AM
Next time you're in your garden with the garden hose , you will be watering the garden and seeing a stream of water just coming out of the end of the hose.
No problem right?
Well that water coming out of the hose, is your rocket and fuel. The hose is your rocket and the water is the fuel coming out of your rocket.
We need to make that hose move though, so what can we do?
Well because the water is only coming out in a steady stream, it has little thrust so we need to create a barrier to make that hose move.
[/quote

Whoa buddy, hang on there! You go on to say that putting your hand in front of the hose will increase the force pushing it back, but have you actually tried this?
Quote
I would imagine everyone who's used a hose has tried this but it will have had no meaning to just about all of them.
I know that turning up the flow will definitely increase the thrust, but I have never experienced an increase in thrust by putting my hand in front of the nozzle.
Quote
I never implied you were. I stated that your hand is a barrier and the closer you put your hand to the hose water coming out of the hose, then at some stage, the closer your hand gets, it will create a more stronger barrier against the water coming out and eventually creating a force against that water, so it creates a small force on your hand and also on the water, in which case, the hose is forced back the closer your hand gets. go and try it...I have.

This would be worth setting up as an experiment, arranging the hose so that thrust with and without a hand in the way of the flow of water could be compared. Seeing as you brought it up, how would you like to do the experiment and let us know what you find?

Yeah, I still get a far more noticeable increase in thrust by turning up the pressure. To feel an increase by putting my hand in the way, I have to almost block the hose off with that hand to feel any difference.
Of course you do, because your water flow is small. now go and turn the water pressure up and do it again and notice the difference.

Tap wide open, water coming out in a seriously high-pressure jet, and still no noticeable back-thrust until the blocking hand is almost right against the end of the hose.
Title: Re: Space Flight
Post by: icanbeanything on June 06, 2013, 05:08:26 AM
I've "grasped" rocket science well enough four years ago. We can exchange allegories all day, but philosophy is not what makes the world work.
Never mind the philosophy. Rockets do not work in how they have told you they work and that's why they are not only useless in a vacuum, they would be rendered as weak as piss in a thin atmosphere unless they could increase thrust to godzilla proportions.

You are using philosophy to draw that conclusion.
Title: Re: Space Flight
Post by: icanbeanything on June 06, 2013, 05:19:25 AM
I've "grasped" rocket science well enough four years ago. We can exchange allegories all day, but philosophy is not what makes the world work.
Never mind the philosophy. Rockets do not work in how they have told you they work and that's why they are not only useless in a vacuum, they would be rendered as weak as piss in a thin atmosphere unless they could increase thrust to godzilla proportions.

You are using philosophy to draw that conclusion.
Is this all you have left to give?

Well, after 12 pages of rocket physics discussion, I guess so.

Look, philosophy is when you come up with (meaning imagine) a way that something works. You use imagination, and then reasoning based on that, to explain why something happens the way it does.

Physics is not like this. Physics is exact. It tells you exactly how something works. Most of the process is similar, except for the first step: in physics, you don't just come up with some idea out of nothing, for it to be built upon afterwards.
Title: Re: Space Flight
Post by: icanbeanything on June 06, 2013, 05:21:53 AM
For instance, your whole theory on rockets is based on the initial assumption that they work by pushing themselves on the atmosphere (or otherwise, medium) they're placed in. The rest of your reasoning following that is fine.

It's just that, your initial assumption is just out of nowhere. And if it's wrong, the rest of your reasoning has nothing to be based upon, and that's why it can't be considered absolutely correct.
Title: Re: Space Flight
Post by: icanbeanything on June 06, 2013, 05:26:37 AM
Physics, just like mathematics, is exact. Nothing related to physics can be twisted.

It is hard to understand how this is possible with anything, unless you study some math. Then, you'll understand that there's no place for twisting in it.
Title: Re: Space Flight
Post by: Scintific Method on June 06, 2013, 05:27:37 AM
Tap wide open, water coming out in a seriously high-pressure jet, and still no noticeable back-thrust until the blocking hand is almost right against the end of the hose.
Did your hose push back as your hand moved closer?

Not until my hand was nearly blocking the flow. With my hand more than an inch or so away from the end of the hose, there is no noticeable difference in thrust unless I actually vary the rate of flow by turning the tap.

If I can set up a rig, I'll do some measurements and post some data, but you should really do that yourself, since you did suggest this experiment.
Title: Re: Space Flight
Post by: icanbeanything on June 06, 2013, 05:28:01 AM
But it is absolutely correct.
Search your logical mind and have a serious think about it, as I know you are intelligent...so use that intelligence with logic instead of just going into debunk mode without reason.

I am not in debunk mode. I'm doing exactly what you suggest me to do. I've been doing that my whole life.

You consider your initial assumption to be correct, but there's possibility it isn't. You just don't want to look at it that way.
Title: Re: Space Flight
Post by: icanbeanything on June 06, 2013, 05:41:36 AM
If I can be proved wrong, I'll accept that. I just know that I am 100% correct on this.
Rockets need atmosphere to work and will not work inside a vacuum.

Trying the inflated balloon in a vacuum would, for instance, show that it's possible.
Title: Re: Space Flight
Post by: icanbeanything on June 06, 2013, 06:02:33 AM
If I can be proved wrong, I'll accept that. I just know that I am 100% correct on this.
Rockets need atmosphere to work and will not work inside a vacuum.

Trying the inflated balloon in a vacuum would, for instance, show that it's possible.
I agree. I know it wouldn't work though but we need a big enough vacuum to prove it would simply expend it's air and lay there on the bottom of the vacuum chamber where it was originally.

A standard large vacuum chamber would be big enough. If you want, I can calculate how low the air pressure would end up after the balloon expended all of its contents.
Title: Re: Space Flight
Post by: icanbeanything on June 06, 2013, 06:10:28 AM
There's no need to. If a big enough chamber could be got and the balloon placed inside it...it would be clearly evident immediately upon breaching it, as to what will and won't work and I can state right now that the balloon would no go flying about and it should be obvious to anyone else too. Seriously.

Like I said, by my laser experiment, I'm already convinced with my own eyes that rockets work in a vacuum. I suggest you try the balloon thing. Film it for us, so we can see how wrong we were.
Title: Re: Space Flight
Post by: icanbeanything on June 06, 2013, 06:22:59 AM
There's no need to. If a big enough chamber could be got and the balloon placed inside it...it would be clearly evident immediately upon breaching it, as to what will and won't work and I can state right now that the balloon would no go flying about and it should be obvious to anyone else too. Seriously.

Like I said, by my laser experiment, I'm already convinced with my own eyes that rockets work in a vacuum. I suggest you try the balloon thing. Film it for us, so we can see how wrong we were.
If I had a big enough vacuum chamber, I'd be delighted to show you...but I haven't.
Your laser experiment makes no sense at all with what we are talking about to be fair.

You remember me suggesting that you go ask at a nearby university?

And if the laser is unrelated, can you tell me your idea of how that works? The laser being pushed the other way while it's turned on?
Title: Re: Space Flight
Post by: icanbeanything on June 06, 2013, 06:41:30 AM
1. You don't go to a professor, you ask where the lab is and talk to a lab practicant. Practicants are usually doing their master's, they have a bit more free time and may be more interested.
2. Don't tell them what you want to prove (since you probably won't even trust them), just tell them you want to put an inflated balloon in a vacuum, and let it go.

Try to look confident, say it's for a YouTube experiment channel (worry later about putting it there), and ask if they're willing to help you set it up and film it. My bet is, they'll give permission for a practicant to help you out when the chamber is not otherwise in use.
Title: Re: Space Flight
Post by: Shmeggley on June 06, 2013, 07:36:23 AM
1. You don't go to a professor, you ask where the lab is and talk to a lab practicant. Practicants are usually doing their master's, they have a bit more free time and may be more interested.
2. Don't tell them what you want to prove (since you probably won't even trust them), just tell them you want to put an inflated balloon in a vacuum, and let it go.

Try to look confident, say it's for a YouTube experiment channel (worry later about putting it there), and ask if they're willing to help you set it up and film it. My bet is, they'll give permission for a practicant to help you out when the chamber is not otherwise in use.
You are a university professor aren't you...why can't you perform and film this experiment?

Sceptimatic, you've got two beautiful, simple experiments to do. Both could prove either side wrong. You even came up with the hose one on your own, I'm impressed! If you are really interested in the truth you should try at least one. The hose one should be easy to set up. I would try to find some way to measure the force on the hose. Good luck!
Title: Re: Space Flight
Post by: Fizzy Logic on June 06, 2013, 09:21:06 AM
Why don't you join arocketry club an learn something?
Title: Re: Space Flight
Post by: Rama Set on June 06, 2013, 09:46:17 AM
Do you realise how much mass you would need to throw away from you to propel yourself on a chair with any meaning on a level.

(http://)
Well done. You've just proved that it's air against air.

You are just suffering from confirmation bias. You really need to learn for yourself don't you.
Title: Re: Space Flight
Post by: Fizzy Logic on June 06, 2013, 09:52:12 AM
Why don't you join arocketry club an learn something?
It would be pretty pointless if they are all relying on bogus science wouldn't it.
It would be ok just to go and watch them fly rockets though, even though they are misinformed as to how they really work.

You could see their experimentation, your could see if their calculations are accurate, you could have some information, you could confront your ideas...
Title: Re: Space Flight
Post by: Rama Set on June 06, 2013, 09:55:32 AM
Do you realise how much mass you would need to throw away from you to propel yourself on a chair with any meaning on a level.

(http://)
Well done. You've just proved that it's air against air.

You are just suffering from confirmation bias. You really need to learn for yourself don't you.
I'm suffering from nothing, except telling the truth. You are suffering from bias by simply rejecting what should be pretty clear to you to at least question what you have been told.

You are not questioning anything. You watched the video and decided it proved your point.
Title: Re: Space Flight
Post by: Fizzy Logic on June 06, 2013, 09:57:31 AM
Why don't you join arocketry club an learn something?
It would be pretty pointless if they are all relying on bogus science wouldn't it.
It would be ok just to go and watch them fly rockets though, even though they are misinformed as to how they really work.

You could see their experimentation, your could see if their calculations are accurate, you could have some information, you could confront your ideas...
What experimentation is that?

Sending rockets high in the atmosphere? May be into space?
Title: Re: Space Flight
Post by: Rama Set on June 06, 2013, 12:52:48 PM
Do you realise how much mass you would need to throw away from you to propel yourself on a chair with any meaning on a level.

(http://)
Well done. You've just proved that it's air against air.

Actually it doesn't prove that it is "air against air" or the force of the expelled gas acting upon the bottle. The demonstration is useless as proof of either of those hypotheses. All that demonstration proves is that your assertion that it takes a great deal of energy to propel yourself is incorrect.

It's the laws of motion that prove that the bottle is propelled by the equal and opposite force that the gas generates.

You realize that if a scientist was able to prove the laws of motion wrong they would instantly get a nobel prize and become the most famous person on earth, right? If they were going to be disproved they would have been disproved by now.

They could be disproved still, but the chances of if happening on the scale of interactions we experience in everyday life might as well be nil. It would be on the quantum or on the cosmological scale that we would see this.
Title: Re: Space Flight
Post by: icanbeanything on June 07, 2013, 08:38:30 AM
People like the above picture are the puppets of mainstream science, just like Hawking and Cox, etc.

You don't even know what you're talking about. Einstein's theories completely disregarded those of classical physics. He was a nonconformist and a rebel in the scientific sense and not at all a follower of the mainstream acceptance of absolute time.

And guess what? He's the most famous scientist in the history of science and regarded as having made some of the greatest scientific discoveries in history.

Go read a history book. Your ignorance is shocking.

He's right, Scepti. Einstein wasn't known for his "hugely popular" theories at first. He did become part of the mainstream pretty quick though, since everyone saw he was right.

And once he was "mainstream", he also rejected the work of other "fringe" scientists who later proved they were right, like Scrödinger.
Title: Re: Space Flight
Post by: Rama Set on June 07, 2013, 09:44:38 AM
People like the above picture are the puppets of mainstream science, just like Hawking and Cox, etc.

You don't even know what you're talking about. Einstein's theories completely disregarded those of classical physics. He was a nonconformist and a rebel in the scientific sense and not at all a follower of the mainstream acceptance of absolute time.

And guess what? He's the most famous scientist in the history of science and regarded as having made some of the greatest scientific discoveries in history.

Go read a history book. Your ignorance is shocking.
I could say that your naivety is shocking but I've come to expect it from round earth indocs.

But then it appears you are arguing from ignorance, so it's all a wash anyway.
Title: Re: Space Flight
Post by: Rama Set on June 07, 2013, 09:50:22 AM
People like the above picture are the puppets of mainstream science, just like Hawking and Cox, etc.

You don't even know what you're talking about. Einstein's theories completely disregarded those of classical physics. He was a nonconformist and a rebel in the scientific sense and not at all a follower of the mainstream acceptance of absolute time.

And guess what? He's the most famous scientist in the history of science and regarded as having made some of the greatest scientific discoveries in history.

Go read a history book. Your ignorance is shocking.
I could say that your naivety is shocking but I've come to expect it from round earth indocs.

But then it appears you are arguing from ignorance, so it's all a wash anyway.
We could sit and tit for tat all day long as to who the ignorant one is but it's not going to achieve anything , is it.

Does that mean you will stop?
Title: Re: Space Flight
Post by: icanbeanything on June 07, 2013, 09:57:09 AM
People like the above picture are the puppets of mainstream science, just like Hawking and Cox, etc.

You don't even know what you're talking about. Einstein's theories completely disregarded those of classical physics. He was a nonconformist and a rebel in the scientific sense and not at all a follower of the mainstream acceptance of absolute time.

And guess what? He's the most famous scientist in the history of science and regarded as having made some of the greatest scientific discoveries in history.

Go read a history book. Your ignorance is shocking.

He's right, Scepti. Einstein wasn't known for his "hugely popular" theories at first. He did become part of the mainstream pretty quick though, since everyone saw he was right.

And once he was "mainstream", he also rejected the work of other "fringe" scientists who later proved they were right, like Scrödinger.
Read what you wrote and piece the jigsaw together.
He didn't just become mainstream. he was chosen as the face of it, because they needed a puppet who people could connect with, so they invent the genius is Einstein who was basically just an ordinary man.
When their theories were faltering, they had to invent something magical to cater for it and to sell it, they used the supposed genius that was Einstein to put his mad professor face to it all.

"Oh, yes, we did make some miscalculations and we wondered why things didn't fit but Mr Einstein solved it thankfully by theorising "special relativity."

They pull the same stuff with Hawking...used simply as their puppet and have us believe that his mind can communicate with a speak and spell, yet most of the sheep believe Hawking the so called genius would love to keep his old speak and spell voice, because....wellll...everyone knows that voice.

Wake up man, it's all there in your face and they aren't just taunting us all with it...they are slapping it , bang smack into our faces.

You feel like they're slapping it into your face because you don't understand it. I do.

It's you who should wake up and see that things aren't like you imagine them. There's a wonderful order to our universe, and it's not stitched together from random parts. The truth doesn't care what you believe, but still it would be so much better for you to see it for what it really is.
Title: Re: Space Flight
Post by: Shmeggley on June 07, 2013, 10:13:43 AM
People like the above picture are the puppets of mainstream science, just like Hawking and Cox, etc.

You don't even know what you're talking about. Einstein's theories completely disregarded those of classical physics. He was a nonconformist and a rebel in the scientific sense and not at all a follower of the mainstream acceptance of absolute time.

And guess what? He's the most famous scientist in the history of science and regarded as having made some of the greatest scientific discoveries in history.

Go read a history book. Your ignorance is shocking.

He's right, Scepti. Einstein wasn't known for his "hugely popular" theories at first. He did become part of the mainstream pretty quick though, since everyone saw he was right.

And once he was "mainstream", he also rejected the work of other "fringe" scientists who later proved they were right, like Scrödinger.
Read what you wrote and piece the jigsaw together.
He didn't just become mainstream. he was chosen as the face of it, because they needed a puppet who people could connect with, so they invent the genius is Einstein who was basically just an ordinary man.
When their theories were faltering, they had to invent something magical to cater for it and to sell it, they used the supposed genius that was Einstein to put his mad professor face to it all.

"Oh, yes, we did make some miscalculations and we wondered why things didn't fit but Mr Einstein solved it thankfully by theorising "special relativity."

They pull the same stuff with Hawking...used simply as their puppet and have us believe that his mind can communicate with a speak and spell, yet most of the sheep believe Hawking the so called genius would love to keep his old speak and spell voice, because....wellll...everyone knows that voice.

Wake up man, it's all there in your face and they aren't just taunting us all with it...they are slapping it , bang smack into our faces.

It would be nice if for once you would show some evidence that this actually happened rather than just making up stories.
Title: Re: Space Flight
Post by: icanbeanything on June 07, 2013, 10:14:36 AM
That's the thing though. I don't have to have my head filled full of shitty equations to see what's around me and what's in the sky.

But, like you said yourself, our eyesight isn't perfect, it can easily deceive us. Equations don't lie.
Title: Re: Space Flight
Post by: Rama Set on June 07, 2013, 12:32:59 PM
I explained to you before that Hawkings does not have ALS but a related and less deadly disease. He has lived longer than the average, but its not as crazy as you want it to be.
Title: Re: Space Flight
Post by: DuckDodgers on June 07, 2013, 12:51:38 PM
I explained to you before that Hawkings does not have ALS but a related and less deadly disease. He has lived longer than the average, but its not as crazy as you want it to be.
Less deadly? Of course it's less deadly, he's in his 70's and living longer than most healthy people manage.
Why don't you look up what life span he was given when he found out he had it and then come back and tell me it's not crazy.

People with terminal illnesses can and do live well past their life expectancies.   Look it up,  it happens.   And someone like him would likely have access to some very good medical care,  much better than you average person.
Title: Re: Space Flight
Post by: DuckDodgers on June 07, 2013, 01:18:41 PM
Just giving you possible reasons he has been able to live as long as he has that don't include a conspiracy.   Take it for what you want,  I already knew before posting you would brush it off as nonsense.
Title: Re: Space Flight
Post by: hoppy on June 07, 2013, 01:36:23 PM
This is what awaits anyone who goes into space, if it's the vacuum we are told.

Vakuum im Kesselwagen / Implodiert (http://#)
Why Scepti, surely you must know that the light weight shuttles and lunar landers are stronger than that steel tank.
Title: Re: Space Flight
Post by: DuckDodgers on June 07, 2013, 01:40:12 PM
Thank God for scepti the life saver.   That's actually the opposite of what could happen in the vacuum of space,  but nice try.   Vacuum chambers don't implode so we obviously can make objects to withstand the pressure differentials.
Title: Re: Space Flight
Post by: markjo on June 07, 2013, 01:45:47 PM
Why Scepti, surely you must know that the light weight shuttles and lunar landers are stronger than that steel tank.
Just as an FYI, the atmospheric pressure inside the lunar module was maintained at 5 psi while in space.  That's about 1/3 the pressure at sea level on earth.
Title: Re: Space Flight
Post by: DuckDodgers on June 07, 2013, 02:12:27 PM
All of you analogies have greater pressure outside than inside thus causing implosion.   If the air is trying to rush out,  it is going to find any weakness and use it causing a larger and larger while until the structure stabilizes.   The result would be a gaping hole but not a crushed vehicle.  See what happens when you put some water and the powder found in an mre inside a sealed 2 liter.  This is an example of higher internal pressure than external. 
Title: Re: Space Flight
Post by: Shmeggley on June 07, 2013, 02:13:28 PM
Why Scepti, surely you must know that the light weight shuttles and lunar landers are stronger than that steel tank.
Just as an FYI, the atmospheric pressure inside the lunar module was maintained at 5 psi while in space.  That's about 1/3 the pressure at sea level on earth.
Look Marko. It doesn't matter what they say the pressure was...the vacuum of space is the vacuum of space..it does not have prejudice...it awaits the ever willing 5/10/15 or 10 million psi...all the air wants to do, is fill the vacuum and it will expand and breach the container or rocket to do that.

Since you're so sure that it's impossible to contain a pressure of 5 psi, I'll make sure to explain to the flight crew when I fly on Monday that under no circumstances must they pressurize the cabin! I'm sure they and all the passengers on board will thank me for saving their lives!
Title: Re: Space Flight
Post by: DuckDodgers on June 07, 2013, 02:22:38 PM
All of you analogies have greater pressure outside than inside thus causing implosion.   If the air is trying to rush out,  it is going to find any weakness and use it causing a larger and larger while until the structure stabilizes.   The result would be a gaping hole but not a crushed vehicle.  See what happens when you put some water and the powder found in an mre inside a sealed 2 liter.  This is an example of higher internal pressure than external.
Do you know what an actual implosion is and how it happens. If not I'll be glad to explain it to you and as to why you are wrong in what you said.

Please explain it to me.
Title: Re: Space Flight
Post by: Shmeggley on June 07, 2013, 02:45:53 PM
Why Scepti, surely you must know that the light weight shuttles and lunar landers are stronger than that steel tank.
Just as an FYI, the atmospheric pressure inside the lunar module was maintained at 5 psi while in space.  That's about 1/3 the pressure at sea level on earth.
Look Marko. It doesn't matter what they say the pressure was...the vacuum of space is the vacuum of space..it does not have prejudice...it awaits the ever willing 5/10/15 or 10 million psi...all the air wants to do, is fill the vacuum and it will expand and breach the container or rocket to do that.

Since you're so sure that it's impossible to contain a pressure of 5 psi, I'll make sure to explain to the flight crew when I fly on Monday that under no circumstances must they pressurize the cabin! I'm sure they and all the passengers on board will thank me for saving their lives!
And why do you think planes are pressurised high up and not below a certain height?

Have a good think about it and then you can have a word with the cabin crew.

I'm not sure what you mean. At 35000 feet the air pressure inside the cabin is about 11.3 psi, and the pressure outside is 3.5 psi, the difference is 7.8 psi. You said that you can't even contain 5 psi. Somehow every flight I have ever been on the cabin has not exploded. So I'd say you must be wrong.
Title: Re: Space Flight
Post by: markjo on June 07, 2013, 03:00:12 PM
Look Marko. It doesn't matter what they say the pressure was...the vacuum of space is the vacuum of space..it does not have prejudice...it awaits the ever willing 5/10/15 or 10 million psi...all the air wants to do, is fill the vacuum and it will expand and breach the container or rocket to do that.
Do you know what a barometer is?  Do you understand how it works?
(http://24.media.tumblr.com/tumblr_l552gciyJH1qbtjkwo1_500.png)
Why does the atmosphere crush the top of the glass tube where there is a vacuum.  Why does air not force its way through the mercury to fill the void? 
Title: Re: Space Flight
Post by: Scintific Method on June 07, 2013, 03:04:25 PM
I fear differential pressure and partial pressure are concepts that may be beyond scepti, but I'll explain them as best I can anyway.

Differential pressure: the difference in pressure between the inside of a pressurised vessel and the outside. For your average commercial airliner, traveling at 35,000ft, Shmeggly has already provided the numbers: 11.3psi inside, 3.5psi outside, for a differential of 7.8psi. The planes I used to work on went to a differential of 7psi, but they weren't built to fly as high, so didn't need the extra 0.8. Space-going vehicles operate at an atmosphere of 3-5psi, and space is approximately 0psi, for a differential of 3-5psi, less than commercial airliners, and not at all hard to achieve.

Partial pressure: you may be wondering how crews could survive with an air pressure as low as 3psi in something like the shuttle or Apollo modules? Our atmosphere is at 14.7psi at sea level, and consists of almost 21% oxygen, 78% nitrogen, and the remainder is various other gasses. The partial pressure of oxygen at sea level is 21% of 14.7, or about 3.1psi. Since all we need is the oxygen, we can therefore survive in an atmosphere of 100% oxygen at 3psi, which I believe is what they used in the Apollo modules.

Hopefully those were clear enough!
Title: Re: Space Flight
Post by: Shmeggley on June 07, 2013, 03:06:12 PM
Why Scepti, surely you must know that the light weight shuttles and lunar landers are stronger than that steel tank.
Just as an FYI, the atmospheric pressure inside the lunar module was maintained at 5 psi while in space.  That's about 1/3 the pressure at sea level on earth.
Look Marko. It doesn't matter what they say the pressure was...the vacuum of space is the vacuum of space..it does not have prejudice...it awaits the ever willing 5/10/15 or 10 million psi...all the air wants to do, is fill the vacuum and it will expand and breach the container or rocket to do that.

Since you're so sure that it's impossible to contain a pressure of 5 psi, I'll make sure to explain to the flight crew when I fly on Monday that under no circumstances must they pressurize the cabin! I'm sure they and all the passengers on board will thank me for saving their lives!
And why do you think planes are pressurised high up and not below a certain height?

Have a good think about it and then you can have a word with the cabin crew.

I'm not sure what you mean. At 35000 feet the air pressure inside the cabin is about 11.3 psi, and the pressure outside is 3.5 psi, the difference is 7.8 psi. You said that you can't even contain 5 psi. Somehow every flight I have ever been on the cabin has not exploded. So I'd say you must be wrong.
I said it cannot be contained in a vacuum. Why do you want to twist things. Wouldn't you like to get to the truth, or does the truth scare you?

Your plane equalizes the pressure stress on it's fuselage . Don't forget that the plane if travelling at 500 mph .

An example.
If you were in a plane and a big hand (somehow) grabbed hold of the fuselage and started to exert pressure onto it in a squeeze motion, what would you do to counteract it?

Of course, you would up the pressure and push it back until the stresses were evened out right?
See what I'm saying.

I see what you're saying but of course it has no bearing on reality. A 5 psi pressure differential is a 5 psi pressure differential whether in a vacuum or not. The pressure inside an airplane cabin is not there to equalize pressure with the outside, it's to keep people inside from passing out and dying due to lack of oxygen.
Title: Re: Space Flight
Post by: markjo on June 07, 2013, 03:11:54 PM
Look Marko. It doesn't matter what they say the pressure was...the vacuum of space is the vacuum of space..it does not have prejudice...it awaits the ever willing 5/10/15 or 10 million psi...all the air wants to do, is fill the vacuum and it will expand and breach the container or rocket to do that.
Do you know what a barometer is?  Do you understand how it works?
(http://24.media.tumblr.com/tumblr_l552gciyJH1qbtjkwo1_500.png)
Why does the atmosphere crush the top of the glass tube where there is a vacuum.  Why does air not force its way through the mercury to fill the void?
It doesn't crush the top of the glass.
Why not?  There is no air at the top and you said that "all the air wants to do, is fill the vacuum and it will expand and breach the container or rocket to do that."  So why doesn't the atmosphere breach the glass tube and fill the vacuum?
Title: Re: Space Flight
Post by: markjo on June 07, 2013, 03:16:10 PM
Space-going vehicles operate at an atmosphere of 3-5psi, and space is approximately 0psi, for a differential of 3-5psi, less than commercial airliners, and not at all hard to achieve.

For the Apollo missions, this is true.  However, the ISS maintains a 14.7 psi oxygen/nitrogen environment.  A pure oxygen environment would be too dangerous for such a long term mission.
https://en.wikipedia.org/wiki/International_Space_Station#Life_support (https://en.wikipedia.org/wiki/International_Space_Station#Life_support)
Title: Re: Space Flight
Post by: Shmeggley on June 07, 2013, 03:20:13 PM
I fear differential pressure and partial pressure are concepts that may be beyond scepti, but I'll explain them as best I can anyway.

Differential pressure: the difference in pressure between the inside of a pressurised vessel and the outside. For your average commercial airliner, traveling at 35,000ft, Shmeggly has already provided the numbers: 11.3psi inside, 3.5psi outside, for a differential of 7.8psi. The planes I used to work on went to a differential of 7psi, but they weren't built to fly as high, so didn't need the extra 0.8. Space-going vehicles operate at an atmosphere of 3-5psi, and space is approximately 0psi, for a differential of 3-5psi, less than commercial airliners, and not at all hard to achieve.

Partial pressure: you may be wondering how crews could survive with an air pressure as low as 3psi in something like the shuttle or Apollo modules? Our atmosphere is at 14.7psi at sea level, and consists of almost 21% oxygen, 78% nitrogen, and the remainder is various other gasses. The partial pressure of oxygen at sea level is 21% of 14.7, or about 3.1psi. Since all we need is the oxygen, we can therefore survive in an atmosphere of 100% oxygen at 3psi, which I believe is what they used in the Apollo modules.

Hopefully those were clear enough!
Great. I won't argue with that but you are still missing the point.
Air, or pure oxygen or whatever you want, wants to fill the vacuum. That's it's goal and it will not stop...EVER.... until John Connor is terminated.. or until it fills that vacuum.

PSI difference in planes are for passenger comfort and to keep the plane structurally stable, which is fine but it's a side step away from what we are talking about with a vacuum, so let's not use it.

Cabin pressure has NOTHING to do with structural stability.

And if air absolutely will not stop unless it fills a vacuum, how does any air stay on Earth's surface?
Title: Re: Space Flight
Post by: markjo on June 07, 2013, 03:23:27 PM
But it's just a small vacuum and the air cannot get in until it gains enough pressure of which there isn't enough to allow it to breach the small tube with a tiny vacuum.
Size has nothing to do with pressure.  A vacuum is 0 psi whether it's deep space or in a barometer.  The whole of the earth's 14.7 psi can not breach the thin glass of a barometer.  Why should the eternal vacuum of space have any better luck breaching a properly constructed space craft?
Title: Re: Space Flight
Post by: Scintific Method on June 07, 2013, 03:35:48 PM
Space-going vehicles operate at an atmosphere of 3-5psi, and space is approximately 0psi, for a differential of 3-5psi, less than commercial airliners, and not at all hard to achieve.

For the Apollo missions, this is true.  However, the ISS maintains a 14.7 psi oxygen/nitrogen environment.  A pure oxygen environment would be too dangerous for such a long term mission.
https://en.wikipedia.org/wiki/International_Space_Station#Life_support (https://en.wikipedia.org/wiki/International_Space_Station#Life_support)

Well there ya go, I learned something! Thanks markjo!

Air, or pure oxygen or whatever you want, wants to fill the vacuum. That's it's goal and it will not stop...EVER.... until John Connor is terminated.. or until it fills that vacuum.

PSI difference in planes are for passenger comfort and to keep the plane structurally stable, which is fine but it's a side step away from what we are talking about with a vacuum, so let's not use it.

It is the same principle though, so it is relevant. From my post: "Space-going vehicles operate at an atmosphere of 3-5psi, and space is approximately 0psi, for a differential of 3-5psi, less than commercial airliners, and not at all hard to achieve."

To put this another way, let's say both the airliner and the space vehicle (whatever it may be) have a window with an area of 1 square foot. In the airliner, the force on this window is 7.8psi x 144 square inches = 1123.2 pounds. In the space vehicle, the force is (let's go the high side) 5psi x 144 square inches = 720 pounds. Now, 720 is less than 1123.4, so it actually takes less structural strength to hold that window in place in the space vehicle. Even on the ISS, the force on the same window would be 14.7 x 144 = 2116.8, which is pretty big, but not impossible to engineer for. To show how strong we can make things when we want to, the Trieste (a bathyscaphe) was built to withstand pressures of nearly 18,000psi! And it just had perspex windows! (Yes, they were very thick, but they didn't burst)
Title: Re: Space Flight
Post by: markjo on June 07, 2013, 03:40:11 PM
But it's just a small vacuum and the air cannot get in until it gains enough pressure of which there isn't enough to allow it to breach the small tube with a tiny vacuum.
Size has nothing to do with pressure.  A vacuum is 0 psi whether it's deep space or in a barometer.  The whole of the earth's 14.7 psi can not breach the thin glass of a barometer.  Why should the eternal vacuum of space have any better luck breaching a properly constructed space craft?
Here's a clue. psi.
The vacuum of space is 0 psi.  The vacuum in a barometer is 0 psi.  What's the difference between 0 psi in space and 0 psi in a barometer?
Title: Re: Space Flight
Post by: Scintific Method on June 07, 2013, 04:05:07 PM
Space-going vehicles operate at an atmosphere of 3-5psi, and space is approximately 0psi, for a differential of 3-5psi, less than commercial airliners, and not at all hard to achieve.

For the Apollo missions, this is true.  However, the ISS maintains a 14.7 psi oxygen/nitrogen environment.  A pure oxygen environment would be too dangerous for such a long term mission.
https://en.wikipedia.org/wiki/International_Space_Station#Life_support (https://en.wikipedia.org/wiki/International_Space_Station#Life_support)

Well there ya go, I learned something! Thanks markjo!

Air, or pure oxygen or whatever you want, wants to fill the vacuum. That's it's goal and it will not stop...EVER.... until John Connor is terminated.. or until it fills that vacuum.

PSI difference in planes are for passenger comfort and to keep the plane structurally stable, which is fine but it's a side step away from what we are talking about with a vacuum, so let's not use it.

It is the same principle though, so it is relevant. From my post: "Space-going vehicles operate at an atmosphere of 3-5psi, and space is approximately 0psi, for a differential of 3-5psi, less than commercial airliners, and not at all hard to achieve."

To put this another way, let's say both the airliner and the space vehicle (whatever it may be) have a window with an area of 1 square foot. In the airliner, the force on this window is 7.8psi x 144 square inches = 1123.2 pounds. In the space vehicle, the force is (let's go the high side) 5psi x 144 square inches = 720 pounds. Now, 720 is less than 1123.4, so it actually takes less structural strength to hold that window in place in the space vehicle. Even on the ISS, the force on the same window would be 14.7 x 144 = 2116.8, which is pretty big, but not impossible to engineer for. To show how strong we can make things when we want to, the Trieste (a bathyscaphe) was built to withstand pressures of nearly 18,000psi! And it just had perspex windows! (Yes, they were very thick, but they didn't burst)
Ok let's see if I can explain in my simple terms.

You know your vacuum pump on earth right?
Ok and you know that when the air is "sucked" out of it for a short while by a reasonably strong suction pump, the vacuum tube doesn't break right...because it's made of strong stuff and can withstand a reasonably strong suction.
The thing is...if you put a stronger pump on it and left it to suck, it would eventually implode, as in the air pressure will find it's way in, unless that container was so strong that it could withstand a full on full force of the max psi available around it.

If you make that vacuum chamber bigger, it has to be made, equally super strong.because obviously there is more psi acting on a larger surface.
I'm sure you know all this.

Ok , let's transfer this to the vacuum that we are told space is.
Space is an immediate vacuum, meaning, there is no pump sucking anything out...it's just a huge seemingly never ending vacuum, so we are led to believe.

Ok, so now you are putting a rocket into that and we know that the rocket is not made of super thick solid iron ...now tell me what's going to happen when you think of the psi inside of the rocket busting a gut to get out.

That's a common misconception, but when you get right down to the nuts and bolts of it (so to speak), all that really matters is the difference in pressure, and as has been pointed out, that's really not very much, especially when compared to diving down an oceanic trench.

If it was a matter of the ratio of pressure, you would have a point, but it isn't, it's the difference.
Title: Re: Space Flight
Post by: Scintific Method on June 07, 2013, 04:23:41 PM
Scintific Method:

You are seriously underestimating what air pressure at psi can do.

No, I know exactly what it is capable of, I've made great use of it in the past.
Title: Re: Space Flight
Post by: Scintific Method on June 07, 2013, 04:34:38 PM
Scintific Method:

You are seriously underestimating what air pressure at psi can do.

No, I know exactly what it is capable of, I've made great use of it in the past.
Are you interested in finding out the truth? I mean honestly.
If you are, I will show you why rockets could not even get into space, if it was the vacuum we are told .

Scepti, we've been down that road already. I know how these things work, I have played with them for years, I don't even need a scientist to tell me how they work because I worked it out for myself! It just so happens that what the scientists say matches what I worked out through my own observations. What you say has little to no relation to what I have seen for myself, so if you'll excuse me, I won't be putting much value on what you have to say. I will listen, but don't expect me to take it seriously.
Title: Re: Space Flight
Post by: DuckDodgers on June 07, 2013, 04:34:57 PM
All of you analogies have greater pressure outside than inside thus causing implosion.   If the air is trying to rush out,  it is going to find any weakness and use it causing a larger and larger while until the structure stabilizes.   The result would be a gaping hole but not a crushed vehicle.  See what happens when you put some water and the powder found in an mre inside a sealed 2 liter.  This is an example of higher internal pressure than external.
Do you know what an actual implosion is and how it happens. If not I'll be glad to explain it to you and as to why you are wrong in what you said.

Please explain it to me.
Your implosion happens in an atmosphere against a vacuum, not in space. Implosion means a forced in force.
On earth, a vacuum chamber is waiting for air to be forced "into" it....now, if that vacuum chamber was made of ,say...weak aluminium, the more vacuum that's created , the more the air wants in but the air becomes so overpowering, it crushes the aluminium, or in the case of that train container until it equalizes.

In space, it's an explosion in terms of, the air forces itself out but as it does it collapses the container, simply because the air needs to fill that vacuum in super quick time.
In simple terms, imagine blowing up a crisp packet and releasing all of it's air in on go, what do you do?
You smash the bag against your other hand and bang, all the air is gone, leaving you with a flat crisp bag, devoid of air.

I don't doubt your intelligence but you have been swayed by a good explanation of bull shit in this science.
I'm correct.

You are not correct in this assumption.  There is zero pressure in the vacuum of space, meaning that there is no material physically applying a force from outside on the container.  The only force being applies is from the air pressing on this container, and the container's design allows this force to be spread over the container so that it does not rupture.  In the even of a rupture, the air rushes out, but since there is no force being applied to the outside of the container, there is no reason the container would collapse on itself.

High pressure inside, low pressure outside = explosion
High pressure outside, low pressure inside = implosion

Space is low pressure outside, container is high pressure inside = thus is an explosion.

I don't doubt your extreme distaste for very commonsensical physics, but you have been swayed by a massive amount of bullshit.
Title: Re: Space Flight
Post by: DuckDodgers on June 07, 2013, 04:52:22 PM
You just disagreed with the fact that a container that ruptures in space will just blow out and not crumble, and then in the same breath agreed that it would just blow out and not crumble.  You seem to understand the concept of high pressure vs low pressure, I'm not real sure what you issue is with how a rupture in space would occur, other than you obviously don't think space is an empty vacuum.

The air is trying to get out of the container in space because there is 0 pressure in the vacuum of space, high pressure flows to low pressure to try to balance out.  It's the same concept as wind on Earth and your drinking straw.
Title: Re: Space Flight
Post by: DuckDodgers on June 07, 2013, 05:06:07 PM
You just disagreed with the fact that a container that ruptures in space will just blow out and not crumble,
Quote
No I didn't.
and then in the same breath agreed that it would just blow out and not crumble.
Quote
No I didn't.
You seem to understand the concept of high pressure vs low pressure, I'm not real sure what you issue is with how a rupture in space would occur, other than you obviously don't think space is an empty vacuum.
Quote
To argue space, I have to go on what they tell us, in order to argue it, which is why I'm using the vacuum they say.

The air is trying to get out of the container in space because there is 0 pressure in the vacuum of space, high pressure flows to low pressure to try to balance out.  It's the same concept as wind on Earth and your drinking straw.
Quote
With this statement, you honestly don;t realise how close you are to the real truth. I'm being totally serious here.

Okay, so explain a few things to me

1.  Why did that container with the air getting sucked out implode in that video?  Please don't personify the air in the explanation, make it plain and simple.

2.  Why does a submarine crumple in deep water if there is a catastrophic rupture?

3.  What happens if you continually pump air into a sealed container and this container ruptures?

4.  Is there any pressure in space?

5.  Is there pressure in an air filled container in space?

6.  If a vacuum chamber were put into space, what would happen?

7.  If an air filled container ruptures in a vacuum chamber/space, what would cause it to crumple?
Title: Re: Space Flight
Post by: DuckDodgers on June 07, 2013, 06:04:07 PM
Okay, I just wanted to make sure that the effects of pressure in a vacuum were understood.  Glad we could clear that up.
Title: Re: Space Flight
Post by: markjo on June 07, 2013, 06:38:33 PM
No psi in space?
How many psi do you think there are in space?   ???

Quote
You have a rocket with gases at psi and huge in that massive vacuum against a piddly barometer with a tiny vacuum with a tiny area around that vacuum for the air pressure to act upon.
I'd say there is a massive......no, a humongous difference, wouldn't you.
No, I wouldn't.  The principle is exactly the same. 
Title: Re: Space Flight
Post by: markjo on June 07, 2013, 07:37:46 PM
No psi in space?
Quote
No psi in space?
You have a rocket with gases at psi and huge in that massive vacuum against a piddly barometer with a tiny vacuum with a tiny area around that vacuum for the air pressure to act upon.
I'd say there is a massive......no, a humongous difference, wouldn't you. Make sure you quote all of what I said. Instead of making it look like I was wondering if there was no psi in space or not.
How many psi do you think there are in space?   ???
Quote
As they tell us, none...so do not twist things.

Quote
You have a rocket with gases at psi and huge in that massive vacuum against a piddly barometer with a tiny vacuum with a tiny area around that vacuum for the air pressure to act upon.
I'd say there is a massive......no, a humongous difference, wouldn't you.
No, I wouldn't.  The principle is exactly the same.
Quote
Only if the barometer was a complete vacuum, which it isn't.
>o< FOR CRYING OUT LOUD, LEARN HOW TO NEST REPLIES TO QUOTES PROPERLY.  IT MAKES REPLYING TO INDIVIDUAL POINTS A LOT EASIER.

*sigh*  The empty space at the top of a barometer is a complete vacuum.
Title: Re: Space Flight
Post by: markjo on June 07, 2013, 07:46:27 PM
Incorrect Marko.
Trust me, proper nesting of quotes makes keeping track of multiple replies within a post a lot easier.
Title: Re: Space Flight
Post by: markjo on June 07, 2013, 07:58:20 PM
Incorrect Marko.
Trust me, proper nesting of quotes makes keeping track of multiple replies within a post a lot easier.
I'm talking about your barometer vacuum.
Then please explain why I'm incorrect.
Title: Re: Space Flight
Post by: markjo on June 07, 2013, 08:22:36 PM
Because you said it's a complete vacuum and it isn't.
Why is it not a complete vacuum?
Title: Re: Space Flight
Post by: markjo on June 07, 2013, 08:31:29 PM
Because you said it's a complete vacuum and it isn't.
Why is it not a complete vacuum?
Because if it was, it would not still be a barometer.
Why not?  The vacuum is what makes a barometer work.
Title: Re: Space Flight
Post by: markjo on June 07, 2013, 08:48:04 PM
Because you said it's a complete vacuum and it isn't.
Why is it not a complete vacuum?
Because if it was, it would not still be a barometer.
Why not?  The vacuum is what makes a barometer work.
Yes. But that's the point....If it were a perfect vacuum there would be no barometer as the glass tube wouldn't be intact.
If there is no vacuum in the glass tube, then what is supporting the 29 or so inches of mercury in the tube?
Title: Re: Space Flight
Post by: Scintific Method on June 08, 2013, 12:05:11 AM
Scepti, we've been down that road already. I know how these things work, I have played with them for years, I don't even need a scientist to tell me how they work because I worked it out for myself! It just so happens that what the scientists say matches what I worked out through my own observations. What you say has little to no relation to what I have seen for myself, so if you'll excuse me, I won't be putting much value on what you have to say. I will listen, but don't expect me to take it seriously.
Ok, it's up to you,.

I know you like calculations, so here's an easy one for you.

Calculate the overall psi on a vacuum chamber at 0psi.

The chamber is 2 feet square.

I need a bit more to go on, otherwise I'll have to make some assumptions.

What is the outside pressure? I'll assume atmospheric for now, so 14.7psi

What part of the chamber is 2 feet square, and what area do the other sides have? Did you mean 2 feet cubed? as in 2ft wide x 2ft high x 2ft long? I'll assume that's what you meant so that I can actually do a calculation.

Okay, so now we have a chamber in the shape of a cube, with all sides being 2ft x 2ft. that's 4 square feet of area on each of 6 sides, so 24 square feet of area in total. There are 144 square inches in a square foot, so that's 24 x 144 = 3,456 square inches. With an outside pressure of 14.7psi, and an inside pressure of 0psi, the difference in pressure is 14.7psi. So the total pressure on the outside of the vacuum chamber is 14.7 x 3,456 = 50,803.2 pounds.

I realise that sounds like a lot, but it is not an insurmountable challenge for a competent engineer. Not that they would build a vacuum chamber in the shape of a cube, more likely a cylinder, which has a greater inherent strength in it's shape.

Of course, you actually asked for the overall psi on the chamber, which is just 14.7psi. I calculated the overall force on the outsides of the chamber.

Because you said it's a complete vacuum and it isn't.
Why is it not a complete vacuum?
Because if it was, it would not still be a barometer.
Why not?  The vacuum is what makes a barometer work.
Yes. But that's the point....If it were a perfect vacuum there would be no barometer as the glass tube wouldn't be intact.
If there is no vacuum in the glass tube, then what is supporting the 29 or so inches of mercury in the tube?
You need to pay attention.
I said, if the barometer had a "complete" vacuum it would implode the barometer top.

Wait up, the barometer only contains mercury, so what's that empty space at the top? It sure isn't mercury! And it isn't any kind of gas, because the only thing in the tube is mercury. So what is it?
Title: Re: Space Flight
Post by: spaceman spiff on June 08, 2013, 05:59:24 AM
Quote
You people carry on thinking rockets can work in a vacuum, it's no skin off my nose. I'll tell you one thing though...your study on this stuff is built on a lot of fabricated bullshit mixed in with  truths.
The problem is, some or most of you cannot see past your own naive noses.

I sit back laughing when I challenge things with no response...then all of a sudden the same people start to appear with a full on knowledge of the subject and trying to show how I'm wrong.
All these people do is scour about on google or whatever for the answers and try and quickly grasp concepts as they go along, then come out with bullshit that they're all scientists.  ;D

I keep things simple for a reason...something some of you refuse to do, because you are scared to be proven wrong by people who believe anything other than your indoctrinated minds.
Said the one who won't get up the chair and do simple experiments but believe he is right anyway. Also
Quote
Wait up, the barometer only contains mercury, so what's that empty space at the top? It sure isn't mercury! And it isn't any kind of gas, because the only thing in the tube is mercury. So what is it?
Title: Re: Space Flight
Post by: Puttah on June 08, 2013, 08:13:43 AM
You people carry on thinking rockets can work in a vacuum, it's no skin off my nose. I'll tell you one thing though...your study on this stuff is built on a lot of fabricated bullshit mixed in with  truths.
The problem is, some or most of you cannot see past your own naive noses.
Which parts are fabricated and which parts are truth exactly?
Do you believe that momentum is conserved in space?

I sit back laughing when I challenge things with no response...then all of a sudden the same people start to appear with a full on knowledge of the subject and trying to show how I'm wrong.
All these people do is scour about on google or whatever for the answers and try and quickly grasp concepts as they go along, then come out with bullshit that they're all scientists.  ;D
Nope, I knew about this stuff before you even knew you had a problem with RET.


I keep things simple for a reason...something some of you refuse to do, because you are scared to be proven wrong by people who believe anything other than your indoctrinated minds.
I'm not scared to be proven wrong. I've been proven wrong many times in many subjects and simultaneously have proven others wrong. It's how you learn collectively.
You haven't proven us wrong though, you've just made a claim without a basis.
Title: Re: Space Flight
Post by: DuckDodgers on June 08, 2013, 08:41:27 AM
You people carry on thinking rockets can work in a vacuum, it's no skin off my nose. I'll tell you one thing though...your study on this stuff is built on a lot of fabricated bullshit mixed in with  truths.
The problem is, some or most of you cannot see past your own naive noses.
Which parts are fabricated and which parts are truth exactly?
Do you believe that momentum is conserved in space?

I sit back laughing when I challenge things with no response...then all of a sudden the same people start to appear with a full on knowledge of the subject and trying to show how I'm wrong.
All these people do is scour about on google or whatever for the answers and try and quickly grasp concepts as they go along, then come out with bullshit that they're all scientists.  ;D
Nope, I knew about this stuff before you even knew you had a problem with RET.


I keep things simple for a reason...something some of you refuse to do, because you are scared to be proven wrong by people who believe anything other than your indoctrinated minds.
I'm not scared to be proven wrong. I've been proven wrong many times in many subjects and simultaneously have proven others wrong. It's how you learn collectively.
You haven't proven us wrong though, you've just made a claim without a basis.
The very fact that you think a rocket would work in a vacuum, proves you are either unwilling to think for yourself and simply accept what you have read and are told, because of your trust in how scientists say they work, which is 100% clearly wrong.

Have you even considered that you could be wrong about how rockets work?  I know you say you know with 100% certainty that they won't work, but have you seen a rocket engine attempt to fire in a vacuum and it not work?
Title: Re: Space Flight
Post by: DuckDodgers on June 08, 2013, 09:04:56 AM
You people carry on thinking rockets can work in a vacuum, it's no skin off my nose. I'll tell you one thing though...your study on this stuff is built on a lot of fabricated bullshit mixed in with  truths.
The problem is, some or most of you cannot see past your own naive noses.
Which parts are fabricated and which parts are truth exactly?
Do you believe that momentum is conserved in space?

I sit back laughing when I challenge things with no response...then all of a sudden the same people start to appear with a full on knowledge of the subject and trying to show how I'm wrong.
All these people do is scour about on google or whatever for the answers and try and quickly grasp concepts as they go along, then come out with bullshit that they're all scientists.  ;D
Nope, I knew about this stuff before you even knew you had a problem with RET.


I keep things simple for a reason...something some of you refuse to do, because you are scared to be proven wrong by people who believe anything other than your indoctrinated minds.
I'm not scared to be proven wrong. I've been proven wrong many times in many subjects and simultaneously have proven others wrong. It's how you learn collectively.
You haven't proven us wrong though, you've just made a claim without a basis.
The very fact that you think a rocket would work in a vacuum, proves you are either unwilling to think for yourself and simply accept what you have read and are told, because of your trust in how scientists say they work, which is 100% clearly wrong.

Have you even considered that you could be wrong about how rockets work?  I know you say you know with 100% certainty that they won't work, but have you seen a rocket engine attempt to fire in a vacuum and it not work?
You will never in your life, see a rocket work in a vacuum. EVER.

You may see one work in a partial vacuum for nano second if you're lucky.

Have you ever seen a rocket engine attempting to fire in a vacuum?  Just answer this simple question.
Title: Re: Space Flight
Post by: markjo on June 08, 2013, 09:14:25 AM
You will never in your life, see a rocket work in a vacuum. EVER.

You may see one work in a partial vacuum for nano second if you're lucky.
Does this look familiar?
Apollo stage separation (http://#ws)
Title: Re: Space Flight
Post by: Puttah on June 08, 2013, 09:28:56 AM
You people carry on thinking rockets can work in a vacuum, it's no skin off my nose. I'll tell you one thing though...your study on this stuff is built on a lot of fabricated bullshit mixed in with  truths.
The problem is, some or most of you cannot see past your own naive noses.
Which parts are fabricated and which parts are truth exactly?
Do you believe that momentum is conserved in space?

I sit back laughing when I challenge things with no response...then all of a sudden the same people start to appear with a full on knowledge of the subject and trying to show how I'm wrong.
All these people do is scour about on google or whatever for the answers and try and quickly grasp concepts as they go along, then come out with bullshit that they're all scientists.  ;D
Nope, I knew about this stuff before you even knew you had a problem with RET.


I keep things simple for a reason...something some of you refuse to do, because you are scared to be proven wrong by people who believe anything other than your indoctrinated minds.
I'm not scared to be proven wrong. I've been proven wrong many times in many subjects and simultaneously have proven others wrong. It's how you learn collectively.
You haven't proven us wrong though, you've just made a claim without a basis.
The very fact that you think a rocket would work in a vacuum, proves you are either unwilling to think for yourself and simply accept what you have read and are told, because of your trust in how scientists say they work, which is 100% clearly wrong.

Why do you always skip my questions just to repeat the same babble that I've heard so many times from you already?

You think I'm illogical.
You think I'm indoctrinated.
You think that I can't think for myself.

And I don't care.

So now that we have that out of the way, let's skip to the Q and A.

Which parts are fabricated and which parts are truth exactly? Do you believe that momentum is conserved in space?
Title: Re: Space Flight
Post by: markjo on June 08, 2013, 01:12:26 PM
You will never in your life, see a rocket work in a vacuum. EVER.

You may see one work in a partial vacuum for nano second if you're lucky.
Does this look familiar?
Apollo stage separation (http://#ws)
Are you winding me up or what?
It's not very hard to wind you up, is it?

Quote
If you believe this crap, then it's no wonder you won't accept anything other than what N.A.S.A says.
I believe lots of things that lots of different people say.  But that dosen't mean that I believe everything that everyone says.

Quote
I'm shocked at you...unless you are just kidding about mind...which is it?
Here's your chance to show me that you can learn how to properly respond to different parts of my post.  What you want to do is use a close quote tag ("/quote" in brackets instead of quote marks) to separate what I said from the response that you want to type.  You can then open a new quote right before the next block of text that you want to respond to.  Remember, open quote and close quote tags must be used in pairs in order to work properly.

I get the feeling that if you can't even learn how to use quote tags, then there is little chance that you will ever learn any useful physics.
Title: Re: Space Flight
Post by: markjo on June 08, 2013, 01:20:23 PM
From another thread:
I do not believe there is a vacuum in space like we are told.
I believe space is basically a gaseous ocean consisting of different layers of gas, all the way up.
Does this mean that you have changed your mind and now believe that rockets can work in space?
Title: Re: Space Flight
Post by: markjo on June 08, 2013, 08:42:15 PM
From another thread:
I do not believe there is a vacuum in space like we are told.
I believe space is basically a gaseous ocean consisting of different layers of gas, all the way up.
Does this mean that you have changed your mind and now believe that rockets can work in space?
They couldn't reach space, so no.
Why couldn't a rocket reach space?
Title: Re: Space Flight
Post by: Puttah on June 08, 2013, 08:55:37 PM
Not by a rocket, no.

Don't jump the gun scepti. Do you believe that if you were in a vacuum (protected by a suit of course) and you threw a hammer in one direction, then you'd get pushed back in the other? Conservation of momentum, do you believe it works in a vacuum too?

Now, once you answer that question in its entirety without adding your own little tidbit about a rocket's relation to it, do you then believe that momentum will be conserved if you spray an aerosol can?
Title: Re: Space Flight
Post by: Puttah on June 09, 2013, 03:08:53 AM
So near perfect vacuums aren't possible?
Title: Re: Space Flight
Post by: Puttah on June 09, 2013, 05:22:26 AM
So near perfect vacuums aren't possible?
Of course they're possible. Just not a "perfect" one.

That's fine, space isn't a perfect vacuum, so I guess it can work then.
Title: Re: Space Flight
Post by: RyanTG on June 09, 2013, 05:51:10 AM
Ok, so you say space isn't a perfect vacuum. So how close is it to a perfect vacuum then and how did you come to this conclusion.

Either you see what you're buying into and just go with it even though you know it's fabricated bullshit, or you are utterly naive. Which one is it?

How on earth does the light from distant stars reach our planet if space isn't a vacuum? You can't see the sun on a foggy day, why do you believe we can see stars through light years of space if in fact space is not a vacuum and simply layers of this mystical gas?

Light is scattered and absorbed by matter, if there is matter in the way between a star and us, we CANNOT see it. We may be able to detect x-rays, gamma-rays, infrared radiation etc. But as I alluded to in another post, that requires space telescopes.
Title: Re: Space Flight
Post by: RyanTG on June 09, 2013, 06:03:20 AM
Light from stars reaches our earth because they are in earth's outer atmosphere, not in any vacuum or light years away. Your head has been scrambled by indoctrinated Pinocchio science.

Do you just make this up as you go along?
Title: Re: Space Flight
Post by: Puttah on June 09, 2013, 06:16:56 AM
So near perfect vacuums aren't possible?
Of course they're possible. Just not a "perfect" one.

That's fine, space isn't a perfect vacuum, so I guess it can work then.
Ok, so you say space isn't a perfect vacuum. So how close is it to a perfect vacuum then and how did you come to this conclusion.

Either you see what you're buying into and just go with it even though you know it's fabricated bullshit, or you are utterly naive. Which one is it?

It's very close to a perfect vacuum considering that satellites are succumbed to higher concentrations of gaseous particles at their heights than in deeper outer space and they can orbit for very long periods of time without losing too much height to air resistance. The exact figure though? I don't know, but wikipedia says that it can range from 103 molecules / cm3 in cool dense areas and down to 10-4 ions / cm3 in hot diffused regions.

So I don't know how scientists have arrived at the figures they have, because I haven't studied it, but they wouldn't just say "ok let's just make up an answer so we don't sound dumb" so yeah, maybe we should research it?

By the way, while you're going to dismiss that comment above, would you also care to say how you know that space isn't a vacuum? Oh yeah, you can't because it's fabricated bullshit that popped out of your head but you're here to support FET so you said to yourself "ok I'll just make up an answer so I don't sound dumb".
Title: Re: Space Flight
Post by: Puttah on June 09, 2013, 06:19:26 AM
Light from stars reaches our earth because they are in earth's outer atmosphere, not in any vacuum or light years away. Your head has been scrambled by indoctrinated Pinocchio science.

My head is being scrambled by your scepti science.
Title: Re: Space Flight
Post by: blnjms on June 09, 2013, 07:01:11 AM
Light from stars reaches our earth because they are in earth's outer atmosphere, not in any vacuum or light years away. Your head has been scrambled by indoctrinated Pinocchio science.

My head is being scrambled by your scepti science.
I wouldn't expect it to be any other. If you hang on to bull shit, then the truth is going to be Alien to you, isn't it.

One man's bullshit is another man's truth. There's a good reason that round, rotating and revolving earth is commonly accepted and it isn't mass delusion or conspiracy, as much as you want or think it is.
Title: Re: Space Flight
Post by: blnjms on June 09, 2013, 07:42:35 AM
Light from stars reaches our earth because they are in earth's outer atmosphere, not in any vacuum or light years away. Your head has been scrambled by indoctrinated Pinocchio science.

My head is being scrambled by your scepti science.
I wouldn't expect it to be any other. If you hang on to bull shit, then the truth is going to be Alien to you, isn't it.

One man's bullshit is another man's truth. There's a good reason that round, rotating and revolving earth is commonly accepted and it isn't mass delusion or conspiracy, as much as you want or think it is.
There's an excellent reason that the round, rotating and revolving earth is accepted, you are correct.
It's called "mass" indoctrination or brainwashing.
It's a lie and space space rockets in vacuums.

I just said that it ISN'T mass indoctrination or brainwashing. No FE'er has proven that it is. If it were, it would have been uncovered by now. We can go on like this forever or you can WAKE UP and realize that you could be wrong. I know I'm not because I had trouble with round earth as a child and wouldn't accept it until I accepted gravity, which has been proven. I think that the debate boils down to gravity or not. Why on earth would there be brainwashing, indoctrination, conspiracy or what have you that suppresses anything other than gravity? What is so controversial about gravity, round earth, rotation, revolving, space flight, etc.??? I just don't get it.
Title: Re: Space Flight
Post by: RyanTG on June 09, 2013, 08:05:35 AM
No. It's called using common sense and not being naive.

You seem to be under the false impression all natural phenomenon and their subsequent explanations can be derived through common sense alone. Common sense doesn't tell you stars are in earth's outer atmosphere, that is a conclusion you come to when you need to rationalise observations whilst simultaneously refusing the consensus opinion which is that stars are in fact light years away, something nobody disagrees with.

If everybody had your mindset scepti we'd be stuck in the 6th century for eternity. (At least they knew the earth was spherical in the 6th century.)
Title: Re: Space Flight
Post by: blnjms on June 09, 2013, 08:37:18 AM
Scepti, you have your beliefs, but gravity exists whether you believe it does or not. Can you convince me otherwise? Of course not. And I'm not brainwashed...perhaps you are. You obey the dictates of FET. How is that different from what you're accusing me of doing? In the end, it's one man's belief versus another's and I'm sticking by mine, as you appear to be doing by yours. Oh well.
Title: Re: Space Flight
Post by: blnjms on June 09, 2013, 08:50:14 AM
No. It's called using common sense and not being naive.

You seem to be under the false impression all natural phenomenon and their subsequent explanations can be derived through common sense alone. Common sense doesn't tell you stars are in earth's outer atmosphere, that is a conclusion you come to when you need to rationalise observations whilst simultaneously refusing the consensus opinion which is that stars are in fact light years away, something nobody disagrees with.

If everybody had your mindset scepti we'd be stuck in the 6th century for eternity. (At least they knew the earth was spherical in the 6th century.)
If everyone had free minds, we would be so far advanced from now, that todays technology would appear ancient.
Technological advances are governed and suppressed.

So all the technological strides we've made so far should be thrown out the window? Oh yeah, you don't believe in space flight. How silly of me. I'll stick to the current model and stay in awe of our beautiful globe in the solar system in the galaxy in the universe...and those fantastic Hubble space telescope shots!
Title: Re: Space Flight
Post by: Puttah on June 09, 2013, 10:44:27 AM
When you talk to me...cut this 10 to the power shit out. It's not needed to explain anything, except in your mistaken belief that it impresses me or those watching.
lol? You asked me
Ok, so you say space isn't a perfect vacuum. So how close is it to a perfect vacuum then and how did you come to this conclusion.
How did you want me to answer this? With it's REALLLLLY close with 5 whole L's?

And I'm not trying to impress you or anyone else. Magnitudes are taught in early high school and if you can't comprehend it then all that manages to do is impress everyone with your lack of knowledge. Oh oops... I should replace "lack of knowledge" with "dumbness" because I don't want to look like I'm trying to impress anyone with big words  ::)

I'll help you.....Scientists arrive at those answers, because they are fabricated to explain something they know nothing about....or, they are fabricated to hide the real reasons of what is up there.

So either they don't know anything about it while you in your infinite wisdom do, or they know it's not a vacuum and are coming up with fake science to prove what they know isn't true? Genius!

I could tell you why I know space isn't a vacuum but first of all, you need to use your own head as to how powerful "air" pressure is
So how powerful is it? Is it REALLLY or REALLLLLY powerful?

instead of believing it's simply negligible in it's use for rockets , plus it's effects on a vacuum on earth.

You won't do this, because you can't think for yourself and must rely on Pinocchio science to pull you through.
Submarines deal with a much larger pressure difference, and they're ok. Tell us about how you're an expert on the subject of pressure.
Title: Re: Space Flight
Post by: Puttah on June 09, 2013, 11:09:59 AM
I don't need to explain to you how I'm an expert. I can plainly see that you are not and are all hot air and googlified.

I'm not an expert, I'm still in University and majoring in Mathematics with just a minor in Physics, but you're clearly an expert because you've been able to single handedly shut down the entire scientific community - experts and all - with just a few short sentences.

You should take a long hard look at yourself when even the other FEers don't want to back you up.
Title: Re: Space Flight
Post by: Scintific Method on June 09, 2013, 12:54:58 PM
The great thing about scepti's beliefs is that they have no influence on reality. Of course, reality has no influence on scepti's beliefs, and that is a bit of a shame, it would be nice if he actually did some research instead of telling the people who have done it that they got it wrong.

Scepti, you keep saying you know these things with 100% certainty, but how could you? You've never done a single unbiased experiment in your life, as far as I can tell. So instead of saying you know, how about you just say you believe? That at least would be more honest.
Title: Re: Space Flight
Post by: blnjms on June 09, 2013, 01:07:24 PM
No. It's called using common sense and not being naive.

You seem to be under the false impression all natural phenomenon and their subsequent explanations can be derived through common sense alone. Common sense doesn't tell you stars are in earth's outer atmosphere, that is a conclusion you come to when you need to rationalise observations whilst simultaneously refusing the consensus opinion which is that stars are in fact light years away, something nobody disagrees with.

If everybody had your mindset scepti we'd be stuck in the 6th century for eternity. (At least they knew the earth was spherical in the 6th century.)
If everyone had free minds, we would be so far advanced from now, that todays technology would appear ancient.
Technological advances are governed and suppressed.

So all the technological strides we've made so far should be thrown out the window? Oh yeah, you don't believe in space flight. How silly of me. I'll stick to the current model and stay in awe of our beautiful globe in the solar system in the galaxy in the universe...and those fantastic Hubble space telescope shots!
You can stick to what you want. It's no skin off my nose what you do or think.

Scepti, you're probably a nice person but you're stubborn as a mule...or you're really a RE'er and are just toying with us! Hmmm...
Title: Re: Space Flight
Post by: blnjms on June 09, 2013, 02:56:12 PM
You're not being duped, but I can't prove this just like you can't prove to me that I AM being duped. Based on your logic, religion is false as well since we can't see God and weren't there when Jesus was on earth. So...are you religious? I believe in God and Jesus, but I don't believe that the Bible is always literally true like fundamentalists do, nor do I believe that it is perfect because I don't worship the Bible. I could go on but what I'm saying is that I believe that the earth is round, rotating, and revolving around a 93-million-mile-distant sun because that has been proven sufficiently to me. Not that I've been to space but I've seen enough photographic and video evidence to satisfy myself on RE, space travel, etc. Now, I believe that Jesus rose from the dead because it has been proven sufficiently to reliable people who passed this information down.
Title: Re: Space Flight
Post by: Scintific Method on June 09, 2013, 04:11:42 PM
The great thing about scepti's beliefs is that they have no influence on reality. Of course, reality has no influence on scepti's beliefs, and that is a bit of a shame, it would be nice if he actually did some research instead of telling the people who have done it that they got it wrong.

Scepti, you keep saying you know these things with 100% certainty, but how could you? You've never done a single unbiased experiment in your life, as far as I can tell. So instead of saying you know, how about you just say you believe? That at least would be more honest.
Because I don't divulge experiments, does not mean I don't do them.
All I ever see from you lot is.."Oh I've done this and that."
Type or talk is cheap when things like this is discussed, so take it how you will as I do with comments about me.
I'm right and you and others are wrong on this.
Put your logic head on and you will see. If not, I'm not bothered.

Everything you say contradicts what I have observed for myself. Logic dictates that when a statement does not match the observation it relates to, it must be false. So far, that applies to everything you have said. You believe whatever you want to believe scepti, but I know (and have proven) that you are wrong.
Title: Re: Space Flight
Post by: Puttah on June 09, 2013, 09:40:12 PM
Because I don't divulge experiments, does not mean I don't do them.
Oh really? What experiments would they be?

All I ever see from you lot is.."Oh I've done this and that."
Personally, whatever I claim to do I have done. I have no reason to lie because I don't care about impressing the FES since I'm often made to feel like I'm talking to a bunch of children sometimes (your comment on the powers of 10 struck that idea home), and from what I've already seen, whenever FEers ask for experimental results, it's just them stalling and hopefully calling our bluff that we will ever post the data, because when it is posted, they simply reject it without a second thought.

I'm right and you and others are wrong on this.
That's very convincing.

Put your logic head on and you will see. If not, I'm not bothered.
Did you put your logic head on when you decided that the sun doesn't fall into the horizon? Is it your logic head that still hasn't been able to post a diagram explaining how the sun can move off into the distance without actually looking like it does?
Title: Re: Space Flight
Post by: 29silhouette on June 09, 2013, 09:43:49 PM
I could tell you why I know space isn't a vacuum ....
I admit I am curious.
Title: Re: Space Flight
Post by: Rama Set on June 09, 2013, 10:48:46 PM
The great thing about scepti's beliefs is that they have no influence on reality. Of course, reality has no influence on scepti's beliefs, and that is a bit of a shame, it would be nice if he actually did some research instead of telling the people who have done it that they got it wrong.

Scepti, you keep saying you know these things with 100% certainty, but how could you? You've never done a single unbiased experiment in your life, as far as I can tell. So instead of saying you know, how about you just say you believe? That at least would be more honest.
Because I don't divulge experiments, does not mean I don't do them.
All I ever see from you lot is.."Oh I've done this and that."
Type or talk is cheap when things like this is discussed, so take it how you will as I do with comments about me.
I'm right and you and others are wrong on this.
Put your logic head on and you will see. If not, I'm not bothered.

The irony in this statement is staggering.  Scepti-you sit there and tell others how talk is cheap, and then go on to show time and again, that you are too lazy to even read a link (look over our 9/11 conversation about pancake collapses again if you forget you monumental failure to read a single page of text.)  So really all you do is talk... and talk... and talk... It would be outstanding if you could contribute more to a conversation than being the sideshow people pay a quarter to see. 

You say you can tell us why space is not a vacuum?  Well you should, because if you really want to destroy the current view of the Earth, the one that direct human observation to back it up, you are going to have to get ante up and show that you are more than some misanthrope in their mother's basement.

You say you have done experiments?  Why don't you stop being selfish and enlighten the world?  And to save you the trouble, yes, we will doubt you (you have earned it), yes we will ridicule you (you have earned it), but the fact of the matter is, if your experiments actually work, then we will be the ones with egg on our face.

Until such time (when hell freezes over) please try and hold yourself to the same standard you hold others to.  Thanks 10^3000 times!
Title: Re: Space Flight
Post by: markjo on June 13, 2013, 05:31:29 AM
A hot air balloon should tell you all how a rocket works but some of you are so engrossed in your own scientific world, you cannot comprehend how it relates to a rocket.
So you're saying that rockets work because of buoyancy?  ???
Title: Re: Space Flight
Post by: Scintific Method on June 13, 2013, 05:32:54 AM
Average atmospheric pressure at sea level is 14.7psi. That means that the force the atmosphere applies over 1 square inch of surface area of any object is only 14.7psi.

The diameter of the Saturn V (which hundreds of people have watched lift off in person) is 33 feet. That means the area of it's base would have an area of 123,163in2.

So, the most force the atmosphere could apply to the base of the Saturn V would be almost 1,810,500 pounds. The Saturn V weighed 6,200,000 pounds all up.

So even if there was no atmospheric pressure acting on the upper parts of the rocket, there is no way that the atmosphere could even lift the rocket, let alone accelerate it to speeds approaching 1.5 miles per second.

Edit: For the sake of curiosity, the difference in pressure between what is acting downwards on the Saturn V (from the air on top), and what is acting upwards (from the air underneath) is 22,615 pounds (as best I can figure). What this means, is that if the Saturn V weighed less than 22,615 pounds, it would float!
Title: Re: Space Flight
Post by: DuckDodgers on June 13, 2013, 06:50:08 AM
So the hot air expelled by the rocket causes a pressure differential which creates high pressure behind the rocket which then causes the rocket to rise?   Is that the jist of it?
Title: Re: Space Flight
Post by: DuckDodgers on June 13, 2013, 07:05:06 AM
So the hot air expelled by the rocket causes a pressure differential which creates high pressure behind the rocket which then causes the rocket to rise?   Is that the jist of it?
Yep...you're getting there.
You probably won't accept it, because you , like others, seriously underestimate the atmosphere and how it actually works in it's entirety with the rocket.
No offence but you are finding it hard to grasp, because rocket science has told you different.
I could explain it bit by bit using other analogies...but it would mean you have to go through it with me, piece by piece, so we can agree as we go...instead of me typing it all out for people to say, 'no that's not right.'

I think you may be underestimating the fluidity of the atmosphere and overestimating the effects of pressure on an open system,  but what the hell, I'll bite.  Let's see your take on rockets and pressure.
Title: Re: Space Flight
Post by: markjo on June 13, 2013, 07:09:52 AM
A hot air balloon should tell you all how a rocket works but some of you are so engrossed in your own scientific world, you cannot comprehend how it relates to a rocket.
So you're saying that rockets work because of buoyancy?  ???
Not as in water, but very similar, yes.
To understand it, you have to use your common sense, which you have plenty of, yet would rather simply just dismiss every word I type.
You can carry on doing this of course...but it isn't going to help you understand.
???  What makes you think that rockets work by common sense?  There is a reason that "rocket science" is slang for something very difficult and complex.
Title: Re: Space Flight
Post by: DuckDodgers on June 13, 2013, 07:28:50 AM
An open system allows outside elements in and internal elements out.   When talking about creating pressure differentials,  open systems are incredibly inefficient,  most often to get point of not working.   Think of a puddle of brake fluid versus a brake line.   The first is open and the second is closed.
Title: Re: Space Flight
Post by: DuckDodgers on June 13, 2013, 07:49:35 AM
An open system allows outside elements in and internal elements out.   When talking about creating pressure differentials,  open systems are incredibly inefficient,  most often to get point of not working.   Think of a puddle of brake fluid versus a brake line.   The first is open and the second is closed.
Let's use a water bottle rocket as an example here.
You tell me, how you think it works and I'll tell you why you're wrong in thinking it.

The inside of the bottle is pressurized to the point of non containment.    Once this happens the seal breaks and the pressure starts to equalize with the outside environment. In the process,  the high pressure expels the water,  and the bottle moves in the opposite direction due to the conservation of momentum principle,  zero net momentum prior so there must be zero net momentum after.
Title: Re: Space Flight
Post by: DuckDodgers on June 13, 2013, 08:30:08 AM
I can't do diagrams at the moment but I'll simplify.   High pressure pushes the water out one end and the bottle moves in the other because the force cancelling the upward force is non existent.   The diagram a few pages back of the balloon works well enough.   One force backward and an equal and opposite force forward.
Title: Re: Space Flight
Post by: DuckDodgers on June 13, 2013, 09:58:41 AM
I can't do diagrams at the moment but I'll simplify.   High pressure pushes the water out one end and the bottle moves in the other because the force cancelling the upward force is non existent.   The diagram a few pages back of the balloon works well enough.   One force backward and an equal and opposite force forward.
So what exactly is doing the work?...and by what means is it doing the work against the bottle?

The air inside is acting on the top of the bottle as well as the water,  pushing the bottle up and the water down.  So technically the airinside is doing the work.   The water acts as a pressure rrelease valve of sorts.
Title: Re: Space Flight
Post by: Puttah on June 13, 2013, 10:20:47 AM
It's the water that's being released at high velocity due to the pressure difference between the inside and outside of the bottle that is shooting it up. A pressurized bottle (without releasing any water) won't have a force applied to it because the system is closed and there are no external forces present.

It's basically like a hose. You can turn on the water pressure but have the nozzle shut so no water is released, and the hose sits there. Open up the nozzle so water is released and then suddenly the hose will go flying in the opposite direction.

And finally, rockets work in the same way except that it's gas being propelled outwards instead of liquid. Oh, and in case you hadn't figured it out for yourself, the pressure is created by burning the fuel. If you're curious as to how pressure is created by burning of fuels, just ask.
Title: Re: Space Flight
Post by: DuckDodgers on June 13, 2013, 10:41:40 AM
I can't do diagrams at the moment but I'll simplify.   High pressure pushes the water out one end and the bottle moves in the other because the force cancelling the upward force is non existent.   The diagram a few pages back of the balloon works well enough.   One force backward and an equal and opposite force forward.
So what exactly is doing the work?...and by what means is it doing the work against the bottle?

The air inside is acting on the top of the bottle as well as the water,  pushing the bottle up and the water down.  So technically the airinside is doing the work.   The water acts as a pressure rrelease valve of sorts.
So let's just make this clear.
What you are saying is... the air pressure is pushing the top of the bottle whilst pushing the water and once the water is released from the bottle top, the water is useless and it's simply the air inside the bottle sort of shooting it's way up, if you like?

Is this how you think a bottle rocket works?

The water isn't the actual thing producing the work,  but far from useless as this regulates the pressure release from being a nearly instant burst to a more drawn out one.  Going with a personification of air analogy,  it's like a large guy with 2 kids cramping him,  so he pushed them both away.
Title: Re: Space Flight
Post by: DuckDodgers on June 13, 2013, 12:15:16 PM
Can you explain how the gaseous atmosphere can provide much of a resistive force against the stream of water?  Gases and liquid tend to move out of the way for the most part.   Your diagram appears to work if the bottle were in a closed system with no where for the air to go, but that's not the case in open atmo.
Title: Re: Space Flight
Post by: DuckDodgers on June 13, 2013, 02:08:39 PM
Water is very compression resistant,  which makes it hard to excite it with pressure.   And your analogy is that if a closed system where the air molecules can't escape.   In the open atmo, the air can move in any direction and moves out of the way of more dense objects.   Higher velocities meet resistance,  but high velocities meet any substantial resistance (aka terminal velocity).  Even then it doesn't prevent movement,  just stops acceleration.   Think medicine ball sized balloons that are filling and open pain fairly sparsely then apply your hyper kids.   The balloons will get out of the way and but really apply much resistance in the long run afterwards.

Question,  2 identical bottle rockets,  one on a boat on top of the water horizontal and the other underneath a boat horizontal,  both attached to said different boats,  which would go further?
Title: Re: Space Flight
Post by: sokarul on June 13, 2013, 02:26:47 PM
Can you explain how the gaseous atmosphere can provide much of a resistive force against the stream of water?  Gases and liquid tend to move out of the way for the most part.   Your diagram appears to work if the bottle were in a closed system with no where for the air to go, but that's not the case in open atmo.
Ok, Ill explain as clear as I can.

Water is denser than atmospheric pressure, so if you had a bottle full of water and poured it out, it would simply hit the ground with very little resistance, because the water simply pushes it out of the way in a thin stream of dense mass. The air cannot compress water and the water wants to be on the ground.
It's like letting loose a dense 'slow' locomotive against the air.

If you put that same water under very high pressure and aim it at the atmosphere... the molecules in that water become excited and act like a billion 'rubber kids trying to run from the back of a bus, constantly in a stream... onto a  field full of  stacked up medicine balls...meaning the 'rubber' kids will spread out in a race to see  who can run through the medicine balls to get the furthest in... and finding that they get stopped very quickly...ending up compressing against the medicine balls due to the speed they ran at them...whilst the other kids behind them... run  in to them and compress against those. And so on and so on, until all the kids running off of the bus hit a barrier which forces the bus away from them...and that's your bottle rocket.

Your burning fuel rocket works in a slightly different way...but the principle is exactly the same= outside force on the rockets expelled fuel.
The rocket cannot work against itself and that should be as clear as day to anyone willing to question the bullshit that scientists tell them...
Still using your ignorance as evidence for your arguments I see.
Anyone actually have a water rocket still? I think they were banned. I thought of a easy experiment to shut up sceptic.
Title: Re: Space Flight
Post by: Rama Set on June 13, 2013, 04:02:24 PM
Can you explain how the gaseous atmosphere can provide much of a resistive force against the stream of water?  Gases and liquid tend to move out of the way for the most part.   Your diagram appears to work if the bottle were in a closed system with no where for the air to go, but that's not the case in open atmo.
Ok, Ill explain as clear as I can.

Water is denser than atmospheric pressure, so if you had a bottle full of water and poured it out, it would simply hit the ground with very little resistance, because the water simply pushes it out of the way in a thin stream of dense mass. The air cannot compress water and the water wants to be on the ground.
It's like letting loose a dense 'slow' locomotive against the air.

If you put that same water under very high pressure and aim it at the atmosphere... the molecules in that water become excited and act like a billion 'rubber kids trying to run from the back of a bus, constantly in a stream... onto a  field full of  stacked up medicine balls...meaning the 'rubber' kids will spread out in a race to see  who can run through the medicine balls to get the furthest in... and finding that they get stopped very quickly...ending up compressing against the medicine balls due to the speed they ran at them...whilst the other kids behind them... run  in to them and compress against those. And so on and so on, until all the kids running off of the bus hit a barrier which forces the bus away from them...and that's your bottle rocket.

Your burning fuel rocket works in a slightly different way...but the principle is exactly the same= outside force on the rockets expelled fuel.
The rocket cannot work against itself and that should be as clear as day to anyone willing to question the bullshit that scientists tell them...

In order for the rocket to lift off, it needs kinetic energy working on it. How does the kinetic energy get transferred back up the column of propellant?  The energy is clearly shooting away from the rocket the entire time.
Title: Re: Space Flight
Post by: Shmeggley on June 13, 2013, 07:49:06 PM
I can't do diagrams at the moment but I'll simplify.   High pressure pushes the water out one end and the bottle moves in the other because the force cancelling the upward force is non existent.   The diagram a few pages back of the balloon works well enough.   One force backward and an equal and opposite force forward.
So what exactly is doing the work?...and by what means is it doing the work against the bottle?

The air inside is acting on the top of the bottle as well as the water,  pushing the bottle up and the water down.  So technically the airinside is doing the work.   The water acts as a pressure rrelease valve of sorts.
So let's just make this clear.
What you are saying is... the air pressure is pushing the top of the bottle whilst pushing the water and once the water is released from the bottle top, the water is useless and it's simply the air inside the bottle sort of shooting it's way up, if you like?

Is this how you think a bottle rocket works?

The water isn't the actual thing producing the work,  but far from useless as this regulates the pressure release from being a nearly instant burst to a more drawn out one.  Going with a personification of air analogy,  it's like a large guy with 2 kids cramping him,  so he pushed them both away.
You are wrong.

If the air is pushing down on the water, it's creating an equal force up against the top of the rocket and against the water.
The harder the air pushes against the top...it has to push against the water with equal pressure.
The fact that the top cannot be breached, the air acts on the water, all the way down...'equally.'

the air cannot push the inside of the rocket 'up' because it's acting against an equal weight below, all the time.
The only thing that can push that rocket up, is...the expelling of the water at force against the atmosphere.
The water is at a higher and denser pressure than the atmosphere under it...so the atmosphere under it wants to equalize that pressure and immediately attacks it  and forces its way through is a sort of one winner friction fight, which the atmosphere below the rocket cannot lose, so your rocket gets pushed up.

Here is a diagram showing what I mean.

(http://img153.imageshack.us/img153/9493/bottlepressuresinrocket.png) (http://imageshack.us/photo/my-images/153/bottlepressuresinrocket.png/)

This diagram makes about as much sense as pushing on a rope.
Title: Re: Space Flight
Post by: Scintific Method on June 14, 2013, 01:04:36 AM
I'm correct and you are wrong.

Prove it.
Title: Re: Space Flight
Post by: Scintific Method on June 14, 2013, 02:11:17 AM
I'm correct and you are wrong.

Prove it.
I just have. See diagram.

You mean the one where you say the pressure inside the bottle is the same as the pressure outside? How is the water forced out of the bottle then? If the internal pressure and external pressure were the same, the water would not be forced out in a jet.

Going back a few pages, do you recall the example with the person stepping out of the boat? Why did the boat move back, even though water offers much greater resistance to movement than air? Applying that example to the classic water rocket, the water going one way is the person stepping out, and the bottle is the boat.
Title: Re: Space Flight
Post by: markjo on June 14, 2013, 05:25:34 AM
Quote from: Scintific Method
You mean the one where you say the pressure inside the bottle is the same as the pressure outside? How is the water forced out of the bottle then? If the internal pressure and external pressure were the same, the water would not be forced out in a jet.
Why don't you take note of the diagram and what I said and you might not jump to conclusions.
I said, the pressure 'equalizes' meaning the pressure inside the bottle pushing against the sides, is 'equally counteracted by the air pressure outside. What can't you understand about this?
This is the whole reason the air is under the pressure it is.
Because it's the plastic of the bottle itself holding back the pressure inside, not the air outside.  Yes, the air outside and the air inside want to equalize, but there is a plastic bottle holding them apart.
Title: Re: Space Flight
Post by: Scintific Method on June 14, 2013, 05:27:04 AM
Quote from: Scintific Method
You mean the one where you say the pressure inside the bottle is the same as the pressure outside? How is the water forced out of the bottle then? If the internal pressure and external pressure were the same, the water would not be forced out in a jet.
Why don't you take note of the diagram and what I said and you might not jump to conclusions.
I said, the pressure 'equalizes' meaning the pressure inside the bottle pushing against the sides, is 'equally counteracted by the air pressure outside. What can't you understand about this?
This is the whole reason the air is under the pressure it is.

This may be a poor choice of wording on your part scepti. By saying that the pressure equalises, you are implying that the air inside the bottle is at a pressure equal to the air outside the bottle, ie they are both at 14.7psi. Without a pressure difference, the water will not flow out the neck of the bottle. The only thing that allows the pressure inside the bottle to be higher is the compressibility of air (the air inside the bottle is slightly compressed), and the strength of the bottle (your average soft drink bottle is designed to hold an internal pressure of about 30psi, which is a similar pressure to what car tires run at).

Quote from: Scintific Method
Going back a few pages, do you recall the example with the person stepping out of the boat? Why did the boat move back, even though water offers much greater resistance to movement than air? Applying that example to the classic water rocket, the water going one way is the person stepping out, and the bottle is the boat.

Because the man is going one way and kicking the boat the other way. Why is this relevant to how the rocket works.
If he done this time and time again, it would be like him running on a treadmill. Plenty of energy put in, for basically running on the spot.
How will this move a rocket?

If you had 20 people on the boat, and they stepped off one after another, the boat would end up moving along at a pretty good rate. This is equivalent to what happens with a rocket, the only difference being that the rocket expels exhaust gasses instead of people.
Title: Re: Space Flight
Post by: Scintific Method on June 14, 2013, 06:03:36 AM
It's the air outside that is stopping the pressurised plastic from blowing apart. It does this by EQUALIZING the pressure from outside.
It's a big bully atmosphere, remember.
In space...there would be NOTHING to push back against that pressure inside. Guess what would happen?

So, what you're saying is, the gas cylinder I have outside that's storing gas at something like 10,000psi is being held together by atmospheric pressure of 14.7psi?

Quote from: Scintific Method
If you had 20 people on the boat, and they stepped off one after another, the boat would end up moving along at a pretty good rate. This is equivalent to what happens with a rocket, the only difference being that the rocket expels exhaust gasses instead of people.

Those people still need friction to make the boat move.
The energy is in their knees as they jump AWAY from the boat. The friction of the air acts on them immediately as they push forward.

What about the friction of the water? Have you ever tried running through water? It's a lot harder than running through air.

You say it's the person pushing against the air that pushes the boat the other way, but the boat is pushing against the water just as hard, and water resists movement more than air, so the boat should stay put according to your logic.
Title: Re: Space Flight
Post by: DuckDodgers on June 14, 2013, 06:29:17 AM
Scepti, do you have an actual working knowledge of pressure, because it sounds like you are just scratching the surface of its understanding.   Pressure exerts a specific amount of force over an area.  If you were to take a one foot cube pressurized at 20 psi internally (Let's just assume equal area inside and out for simplicity) the external force would be 12, 700.8 lbs pressing inward and 17, 280 lbs of force pressing outward (assuming all 6 sides are exposed to the atmosphere).  There is a much larger force pressing out than in so the construction of the container must account for this.
Title: Re: Space Flight
Post by: Manarq on June 14, 2013, 06:37:45 AM
Scepti, do you have an actual working knowledge of pressure, because it sounds like you are just scratching the surface of its understanding.   Pressure exerts a specific amount of force over an area.  If you were to take a one foot cube pressurized at 20 psi internally (Let's just assume equal area inside and out for simplicity) the external force would be 12, 700.8 lbs pressing inward and 17, 280 lbs of force pressing outward (assuming all 6 sides are exposed to the atmosphere).  There is a much larger force pressing out than in so the construction of the container must account for this.
Yes I do have knowledge about atmospheric pressure, that's why I can tell you that rockets cannot work without it and neither can anything else.
What do you mean by anything else?
Title: Re: Space Flight
Post by: DuckDodgers on June 14, 2013, 06:44:16 AM
Scepti, do you have an actual working knowledge of pressure, because it sounds like you are just scratching the surface of its understanding.   Pressure exerts a specific amount of force over an area.  If you were to take a one foot cube pressurized at 20 psi internally (Let's just assume equal area inside and out for simplicity) the external force would be 12, 700.8 lbs pressing inward and 17, 280 lbs of force pressing outward (assuming all 6 sides are exposed to the atmosphere).  There is a much larger force pressing out than in so the construction of the container must account for this.
Yes I do have knowledge about atmospheric pressure, that's why I can tell you that rockets cannot work without it and neither can anything else.

Atmospheric pressure isn't this magical fix all that acts like a gas at low speeds and a solid at high speeds like you are making it out to be.  I think the best thing for you to do is the experiment someone else suggested and contact a university near you and see if you can use their vacuum chamber.  You obviously cannot be shown just how incorrect you are in your knowledge of the workings of a rocket,  and we obviously aren't buying your explanation because it just doesn't make sense and violates a very basic law of motion that has withstood the test of time as being true.
Title: Re: Space Flight
Post by: Manarq on June 14, 2013, 06:47:00 AM
Scepti, do you have an actual working knowledge of pressure, because it sounds like you are just scratching the surface of its understanding.   Pressure exerts a specific amount of force over an area.  If you were to take a one foot cube pressurized at 20 psi internally (Let's just assume equal area inside and out for simplicity) the external force would be 12, 700.8 lbs pressing inward and 17, 280 lbs of force pressing outward (assuming all 6 sides are exposed to the atmosphere).  There is a much larger force pressing out than in so the construction of the container must account for this.
Yes I do have knowledge about atmospheric pressure, that's why I can tell you that rockets cannot work without it and neither can anything else.
What do you mean by anything else?
Anything that does work, requires atmospheric pressure.
Do you mind defining work in the above context, just so I can be sure I understand what you mean.
Title: Re: Space Flight
Post by: Rama Set on June 14, 2013, 06:47:48 AM
Can you explain how the gaseous atmosphere can provide much of a resistive force against the stream of water?  Gases and liquid tend to move out of the way for the most part.   Your diagram appears to work if the bottle were in a closed system with no where for the air to go, but that's not the case in open atmo.
Ok, Ill explain as clear as I can.

Water is denser than atmospheric pressure, so if you had a bottle full of water and poured it out, it would simply hit the ground with very little resistance, because the water simply pushes it out of the way in a thin stream of dense mass. The air cannot compress water and the water wants to be on the ground.
It's like letting loose a dense 'slow' locomotive against the air.

If you put that same water under very high pressure and aim it at the atmosphere... the molecules in that water become excited and act like a billion 'rubber kids trying to run from the back of a bus, constantly in a stream... onto a  field full of  stacked up medicine balls...meaning the 'rubber' kids will spread out in a race to see  who can run through the medicine balls to get the furthest in... and finding that they get stopped very quickly...ending up compressing against the medicine balls due to the speed they ran at them...whilst the other kids behind them... run  in to them and compress against those. And so on and so on, until all the kids running off of the bus hit a barrier which forces the bus away from them...and that's your bottle rocket.

Your burning fuel rocket works in a slightly different way...but the principle is exactly the same= outside force on the rockets expelled fuel.
The rocket cannot work against itself and that should be as clear as day to anyone willing to question the bullshit that scientists tell them...

In order for the rocket to lift off, it needs kinetic energy working on it. How does the kinetic energy get transferred back up the column of propellant?  The energy is clearly shooting away from the rocket the entire time.
It has kinetic energy. Translational.

How does the kinetic energy travel from the base of the propellant column to the mass of the rocket when the propellant column is constantly sending kinetic energy away from the rocket's mass? 
Title: Re: Space Flight
Post by: Puttah on June 14, 2013, 06:53:09 AM
Oh scepti, I leave you for the day and you manage to shit all over everything.

There's nothing to see here folks. The scepti science is still a work in progress but I assure you it'll soon revolutionize everything we understand about our world. And the best thing about it is you won't even need to conduct any experiments, and screw numbers (mainly powers of 10) as they're useless indoctrinations too.
Title: Re: Space Flight
Post by: DuckDodgers on June 14, 2013, 06:53:21 AM
The only law it violates, is the law of bull shit science.
It's already been shown to you how your idea violates the law of conservation of motion and by extension the equal and opposite force.   Mass is accelerated out the back of the bottle or rocket, this is a force.   Forces do not exist without their pair.   So since a force is applied out the back,  the same amount of force is applied to the front.  It is literally as simple as that.
Title: Re: Space Flight
Post by: DuckDodgers on June 14, 2013, 07:01:40 AM
Everything didn't require atmospheric pressure to work,  everything works with atmospheric pressure.   There is a major difference in those two statements.  There are plenty of things that work with more and less pressure,  our lungs included.  Oxygen is the key to what just about everything needs to work.
Title: Re: Space Flight
Post by: Manarq on June 14, 2013, 07:03:41 AM
You staying alive. Your lungs have to work against the atmospheric pressure to take a breath.
A vehicle requires air to work.
Anything 'on' earth, requires atmospheric pressure to enable it to work.
Basically, to use energy, we need an atmosphere.
What about an electric motor powered by solar power or a battery?
Title: Re: Space Flight
Post by: DuckDodgers on June 14, 2013, 07:07:23 AM
The only law it violates, is the law of bull shit science.
It's already been shown to you how your idea violates the law of conservation of motion and by extension the equal and opposite force.   Mass is accelerated out the back of the bottle or rocket, this is a force.   Forces do not exist without their pair.   So since a force is applied out the back,  the same amount of force is applied to the front.  It is literally as simple as that.
You know... you sort of grasp it...but you can't quite get there.
This is because you refuse to release your grip of the official 'how rockets work' theory.

You are correct. Forces do not exist 'on earth' without an equal to it. It's just a shame you send your reactionary force inside rockets arse end.
This is the only problem you are having.

The ass end of the rocket is where the mass is being ejected.   It follows suit that the opposite force must be within the rocket as well.   The atmosphere does some work on the expelled matter,  but that cannot travel back up the continuously flowing matter unless it were still attached to the rocket.
Title: Re: Space Flight
Post by: Puttah on June 14, 2013, 07:17:07 AM
In vacuum chambers, do the laws of physics not work the same way they do in a regular atmosphere? If that pressurized water bottle were to be released in the chamber, it wouldn't shoot water out of one end and the bottle fly away in the other? Is this what you're saying?
Title: Re: Space Flight
Post by: DuckDodgers on June 14, 2013, 07:33:29 AM


Quote from: DuckDodgers
The ass end of the rocket is where the mass is being ejected.   It follows suit that the opposite force must be within the rocket as well.   The atmosphere does some work on the expelled matter,  but that cannot travel back up the continuously flowing matter unless it were still attached to the rocket.
Correct, it doesn't travel back up the rockets arse end.
It fights off the mass of hot, severely unbelievably fast hot gases trying to barge their way through it and the dense atmosphere cannot do much against the really hot parts, other than to exert a push against it but cannot penetrate it, so it waits till it slows down, because all it can do , under the hot flame is try and slow it down until it eventually does stop it and then starts to push it back.

This is carried on in nano seconds all the way up, or as long as the rocket has hot thrusting force.

If you have ever tried to push up on a stream of water coming out of a bottle or tried to push on a rope you will see how that explanation makes 0 sense.
Title: Re: Space Flight
Post by: Puttah on June 14, 2013, 07:46:22 AM
In vacuum chambers, do the laws of physics not work the same way they do in a regular atmosphere? If that pressurized water bottle were to be released in the chamber, it wouldn't shoot water out of one end and the bottle fly away in the other? Is this what you're saying?
The air in the bottle would expand and burst the bottle, then the vacuum would turn the water to gas and it will be all sucked out, assuming the vacuum pump was still sucking.

I didn't question your understanding about phase diagrams, nor did I ask where the water in the bottle would end up after shooting out. I asked how the motion of the bottle and water would be affected during pressure release. We're discussing physics here, not chemistry or the mechanics of the vacuum chamber.
Title: Re: Space Flight
Post by: Manarq on June 14, 2013, 07:47:13 AM
You staying alive. Your lungs have to work against the atmospheric pressure to take a breath.
A vehicle requires air to work.
Anything 'on' earth, requires atmospheric pressure to enable it to work.
Basically, to use energy, we need an atmosphere.
What about an electric motor powered by solar power or a battery?
How does it stay cool?
Why would it overheat?
Title: Re: Space Flight
Post by: Puttah on June 14, 2013, 07:56:37 AM
In vacuum chambers, do the laws of physics not work the same way they do in a regular atmosphere? If that pressurized water bottle were to be released in the chamber, it wouldn't shoot water out of one end and the bottle fly away in the other? Is this what you're saying?
The air in the bottle would expand and burst the bottle, then the vacuum would turn the water to gas and it will be all sucked out, assuming the vacuum pump was still sucking.

I didn't question your understanding about phase diagrams, nor did I ask where the water in the bottle would end up after shooting out. I asked how the motion of the bottle and water would be affected during pressure release. We're discussing physics here, not chemistry or the mechanics of the vacuum chamber.
It can't happen.
You can not put a air and water bottle into a vacuum, then open it up, as it would immediately expand and blow open the minute it became a vacuum.

When it expands and blows open due to the larger pressure difference, wouldn't the bottle shoot away from the direction the water is being shot out?
Title: Re: Space Flight
Post by: DuckDodgers on June 14, 2013, 07:58:42 AM
In vacuum chambers, do the laws of physics not work the same way they do in a regular atmosphere? If that pressurized water bottle were to be released in the chamber, it wouldn't shoot water out of one end and the bottle fly away in the other? Is this what you're saying?
The air in the bottle would expand and burst the bottle, then the vacuum would turn the water to gas and it will be all sucked out, assuming the vacuum pump was still sucking.

I didn't question your understanding about phase diagrams, nor did I ask where the water in the bottle would end up after shooting out. I asked how the motion of the bottle and water would be affected during pressure release. We're discussing physics here, not chemistry or the mechanics of the vacuum chamber.
It can't happen.
You can not put a air and water bottle into a vacuum, then open it up, as it would immediately expand and blow open the minute it became a vacuum.
Why would it do that?  Things have been designed to accommodate thousands of psi pressure differentials,  this is just a matter of 20 psi difference at the most?
Title: Re: Space Flight
Post by: DuckDodgers on June 14, 2013, 08:02:38 AM


Quote from: DuckDodgers
The ass end of the rocket is where the mass is being ejected.   It follows suit that the opposite force must be within the rocket as well.   The atmosphere does some work on the expelled matter,  but that cannot travel back up the continuously flowing matter unless it were still attached to the rocket.
Correct, it doesn't travel back up the rockets arse end.
It fights off the mass of hot, severely unbelievably fast hot gases trying to barge their way through it and the dense atmosphere cannot do much against the really hot parts, other than to exert a push against it but cannot penetrate it, so it waits till it slows down, because all it can do , under the hot flame is try and slow it down until it eventually does stop it and then starts to push it back.

This is carried on in nano seconds all the way up, or as long as the rocket has hot thrusting force.

If you have ever tried to push up on a stream of water coming out of a bottle or tried to push on a rope you will see how that explanation makes 0 sense.
Because what you are explaining has no relevance to what I've just said.
You need to think.
I've thought about it and I still fail to see how a constant stream of non-rigid matter can transfer any outside kinetic energy in a direction opposite to its movement, i.e. the gas flowing down and atmosphere applying kinetic energy to the rocket up stream.
Title: Re: Space Flight
Post by: Manarq on June 14, 2013, 08:07:58 AM
You staying alive. Your lungs have to work against the atmospheric pressure to take a breath.
A vehicle requires air to work.
Anything 'on' earth, requires atmospheric pressure to enable it to work.
Basically, to use energy, we need an atmosphere.
What about an electric motor powered by solar power or a battery?
How does it stay cool?
Why would it overheat?
Come on man, are you being serious?
If the battery is doing work...it's creating heat and if air isn't there to cool it, then what do you think would happen?
You really need to build yourself a vacuum chamber.
Title: Re: Space Flight
Post by: DuckDodgers on June 14, 2013, 08:10:53 AM

Quote from: DuckDodgers
I've thought about it and I still fail to see how a constant stream of non-rigid matter can transfer any outside kinetic energy in a direction opposite to its movement, i.e. the gas flowing down and atmosphere applying kinetic energy to the rocket up stream.

Go and get a lighter and turn it upside down and light it and tell me what the flame is doing and why it does this.

The flame is a far cry from the lighter itself.  We aren't concerned with what the expelled matter does once it is no longer acting on the rocket.
Title: Re: Space Flight
Post by: DuckDodgers on June 14, 2013, 08:15:30 AM

Quote from: Manarq
You really need to build yourself a vacuum chamber.
It would be good to have one...but I don't need one to think I know what a vacuum would do to stuff.
That seems more accurate.
Title: Re: Space Flight
Post by: markjo on June 14, 2013, 08:20:07 AM
Basically, to use energy, we need an atmosphere.
A flashlight uses energy.  Does a flashlight need an atmosphere?
Title: Re: Space Flight
Post by: Puttah on June 14, 2013, 08:20:58 AM
Yes...but only because it's blew open and made the vacuum cylinder a non vacuum cylinder, so now it can act against the walls of the cylinder and so, blowing the bottle about,as well as the water.

What do you mean by "now it can act against the walls"? Do you expect some kind of delay in the bottle's motion during the time the chamber is still a vacuum versus when it fills up sufficiently with gas?

It's so cute how you call the entire scientific community indoctrinated, while this scepti science is being spewed out from seemingly nowhere. It seems that you think that whatever makes sense in your head must be the answer and I'm sure there exists a very lovely adjective that would describe this type of personality.
Title: Re: Space Flight
Post by: DuckDodgers on June 14, 2013, 08:24:09 AM

Quote from: Manarq
You really need to build yourself a vacuum chamber.
It would be good to have one...but I don't need one to think I know what a vacuum would do to stuff.
That seems more accurate.
If you want to be a prick, then carry on..but you do it without reply from now on.

I wasn't being a prick.   To know what would happen for certain you need to carry out the experiment.   I haven't so I can only make an educated guess as to what would happen.   I'm fairly sure but I do not know.
Title: Re: Space Flight
Post by: Puttah on June 14, 2013, 08:25:36 AM

Quote from: Manarq
You really need to build yourself a vacuum chamber.
It would be good to have one...but I don't need one to know what a vacuum would do to stuff.

So experimentation has otherwise been a big waste of time for humanity.
Title: Re: Space Flight
Post by: Puttah on June 14, 2013, 08:35:16 AM
Quote from: Puttah
What do you mean by "now it can act against the walls"? Do you expect some kind of delay in the bottle's motion during the time the chamber is still a vacuum versus when it fills up sufficiently with gas?
Once the bottle expands and breaks...the air will 'immediately' fill the vacuum and hitting the walls. What part of this can't you get a grip of?

The 'immediately' part. You just quoted me asking if you expect some kind of delay in the bottle's motion, and obviously by the quotations used, you know the air can't hit the walls in zero time.
If we took an even larger vacuum chamber that has walls much further away, will the bottle delay even longer?
Title: Re: Space Flight
Post by: Puttah on June 14, 2013, 08:50:50 AM
Quote from: Puttah
What do you mean by "now it can act against the walls"? Do you expect some kind of delay in the bottle's motion during the time the chamber is still a vacuum versus when it fills up sufficiently with gas?
Once the bottle expands and breaks...the air will 'immediately' fill the vacuum and hitting the walls. What part of this can't you get a grip of?

The 'immediately' part. You just quoted me asking if you expect some kind of delay in the bottle's motion, and obviously by the quotations used, you know the air can't hit the walls in zero time.
If we took an even larger vacuum chamber that has walls much further away, will the bottle delay even longer?
It's about equalizing the pressure.
The bigger the vacuum, the quicker the bottle will expand and pop. In space it will be immediate, no matter what size container is in it.

And how do you know that? Wait, sorry, stupid question...

The atmospheric pressure at 15 psi versus a vacuum at 0 psi is a difference of 15 psi, which is about the same difference as your car's tyres versus the atmosphere. There are many materials that can withstand such forces, so no, the bottle won't necessarily expand and pop.

Actually, you know what? I think it's a valid question and should be answered. So how do you know what you're saying is true, especially when people that have done the experiments have shown results that differ to your description?
Title: Re: Space Flight
Post by: Rama Set on June 14, 2013, 08:52:33 AM
Quote from: Puttah
What do you mean by "now it can act against the walls"? Do you expect some kind of delay in the bottle's motion during the time the chamber is still a vacuum versus when it fills up sufficiently with gas?
Once the bottle expands and breaks...the air will 'immediately' fill the vacuum and hitting the walls. What part of this can't you get a grip of?

The 'immediately' part. You just quoted me asking if you expect some kind of delay in the bottle's motion, and obviously by the quotations used, you know the air can't hit the walls in zero time.
If we took an even larger vacuum chamber that has walls much further away, will the bottle delay even longer?
It's about equalizing the pressure.
The bigger the vacuum, the quicker the bottle will expand and pop. In space it will be immediate, no matter what size container is in it.

This is not true, because the contents of the bottle do not apply more pressure depending on the size of the vaccuum.  If the contents apply 20 psi, then it is always 20 psi.
Title: Re: Space Flight
Post by: DuckDodgers on June 14, 2013, 09:44:04 AM
If you pressurized a tire in a sealed container at atmo,  what would happen to said tire when taken out of the sealed container?
Title: Re: Space Flight
Post by: Antonio on June 14, 2013, 09:49:46 AM
Quote from: Puttah
What do you mean by "now it can act against the walls"? Do you expect some kind of delay in the bottle's motion during the time the chamber is still a vacuum versus when it fills up sufficiently with gas?
Once the bottle expands and breaks...the air will 'immediately' fill the vacuum and hitting the walls. What part of this can't you get a grip of?

The 'immediately' part. You just quoted me asking if you expect some kind of delay in the bottle's motion, and obviously by the quotations used, you know the air can't hit the walls in zero time.
If we took an even larger vacuum chamber that has walls much further away, will the bottle delay even longer?
It's about equalizing the pressure.
The bigger the vacuum, the quicker the bottle will expand and pop. In space it will be immediate, no matter what size container is in it.

This is not true, because the contents of the bottle do not apply more pressure depending on the size of the vaccuum.  If the contents apply 20 psi, then it is always 20 psi.
No it's not.
The air would expand to equalize the pressure of the vacuum, which is zero psi.

We cannot make a complete vacuum on earth but we can get close to it.
If we try to extract air from a cylinder...no matter how strong it is, then sooner or later (assuming we had a suction pump strong enough), the container would implode.

If space is the vacuum we are told it is, then air or fuel will 'try fill it by expansion and no container we know of would contain that expansion, which would not stop until it breached the container.
Remember: there is nothing pushing back against the container like on earth, so it's going to breach and feed the vacuum.

So you haven't tested it and just say , "they do"...
Ok, I suppose your participation in this thread should be over now as you have it all worked out...see yeah. ;)

Well well well...

Title: Re: Space Flight
Post by: Rama Set on June 14, 2013, 09:51:59 AM
Quote from: Puttah
What do you mean by "now it can act against the walls"? Do you expect some kind of delay in the bottle's motion during the time the chamber is still a vacuum versus when it fills up sufficiently with gas?
Once the bottle expands and breaks...the air will 'immediately' fill the vacuum and hitting the walls. What part of this can't you get a grip of?

The 'immediately' part. You just quoted me asking if you expect some kind of delay in the bottle's motion, and obviously by the quotations used, you know the air can't hit the walls in zero time.
If we took an even larger vacuum chamber that has walls much further away, will the bottle delay even longer?
It's about equalizing the pressure.
The bigger the vacuum, the quicker the bottle will expand and pop. In space it will be immediate, no matter what size container is in it.

This is not true, because the contents of the bottle do not apply more pressure depending on the size of the vaccuum.  If the contents apply 20 psi, then it is always 20 psi.
No it's not.
The air would expand to equalize the pressure of the vacuum, which is zero psi.

The air would try to expand yes, but the  net pressure it applies would not go up simply because you are in a vacuum.
Title: Re: Space Flight
Post by: Scintific Method on June 14, 2013, 10:44:39 AM
A vacuum is a vacuum, whether its a small light bulb or the expanse of space, it's still just 0psi.
Title: Re: Space Flight
Post by: DuckDodgers on June 14, 2013, 10:45:07 AM
If you pressurized a tire in a sealed container at atmo,  what would happen to said tire when taken out of the sealed container?
It would blow the container apart before you got it out. It would just compress the air already inside.
Let me rephrase,  if you were inside a sealed room at atmo, no air in or out , and you filled a tire to the proper pressure; what would happen to the tire when you removed it from the sealed room and exposed it to the atmospheric pressure?
Title: Re: Space Flight
Post by: DuckDodgers on June 14, 2013, 11:08:35 AM
If you pressurized a tire in a sealed container at atmo,  what would happen to said tire when taken out of the sealed container?
It would blow the container apart before you got it out. It would just compress the air already inside.
Let me rephrase,  if you were inside a sealed room at atmo, no air in or out , and you filled a tire to the proper pressure; what would happen to the tire when you removed it from the sealed room and exposed it to the atmospheric pressure?
You couldn't do it.

Why?  It should just drop the pressure inside the room a bit too do it,  as well as add a bit more carbon dioxide and other biproducts of the pump.   What makes it impossible?
Title: Re: Space Flight
Post by: naysayer on June 14, 2013, 01:55:33 PM


Quote from: Rama Set
The air would try to expand yes, but the  net pressure it applies would not go up simply because you are in a vacuum.
You have seen a balloon in a vacuum chamber right?
The more air that gets sucked out...the bigger the balloon expands to fill the vacuum and then it pops.
Just like your space rocket would if space is a vacuum and it could reach space.
That's the most stupid thing I've ever read. Why don't scuba tanks explode? Same concept.
Title: Re: Space Flight
Post by: Rama Set on June 14, 2013, 02:47:45 PM


Quote from: Rama Set
The air would try to expand yes, but the  net pressure it applies would not go up simply because you are in a vacuum.
You have seen a balloon in a vacuum chamber right?
The more air that gets sucked out...the bigger the balloon expands to fill the vacuum and then it pops.
Just like your space rocket would if space is a vacuum and it could reach space.

Space craft are not made from a thin sheet of a highly elastic substance. This makes all the difference in the world.
Title: Re: Space Flight
Post by: Puttah on June 14, 2013, 09:11:06 PM
Quote from: Puttah
What do you mean by "now it can act against the walls"? Do you expect some kind of delay in the bottle's motion during the time the chamber is still a vacuum versus when it fills up sufficiently with gas?
Once the bottle expands and breaks...the air will 'immediately' fill the vacuum and hitting the walls. What part of this can't you get a grip of?

The 'immediately' part. You just quoted me asking if you expect some kind of delay in the bottle's motion, and obviously by the quotations used, you know the air can't hit the walls in zero time.
If we took an even larger vacuum chamber that has walls much further away, will the bottle delay even longer?
It's about equalizing the pressure.
The bigger the vacuum, the quicker the bottle will expand and pop. In space it will be immediate, no matter what size container is in it.

And how do you know that? Wait, sorry, stupid question...

The atmospheric pressure at 15 psi versus a vacuum at 0 psi is a difference of 15 psi, which is about the same difference as your car's tyres versus the atmosphere. There are many materials that can withstand such forces, so no, the bottle won't necessarily expand and pop.

Actually, you know what? I think it's a valid question and should be answered. So how do you know what you're saying is true, especially when people that have done the experiments have shown results that differ to your description?
Give yourself 10 minutes to think this through.

If you have a small glass vacuum chamber, then we can agree that it's not wise to use a heavy duty vacuum pump, right?
The reason is very simple: It will implode the chamber due to atmospheric pressure exerting more of it's pressure at it, 'equally' all over the chamber.

The larger the chamber...the stronger it has to be, because it has an enormous amount of psi inside it and an enormous amount surrounding the outside of it, equalizing it from inside and out.

You keep sucking the air out and the outside pressure pushes in because it 'must' equalize that pressure and only the strength of the chamber is in it's way.
Keep sucking the air out and the air pressure outside will just keep exerting it's force.

If you don't release all of the air inside the chamber, then it may hold up against the atmospheric pressure ...but if the chamber isn't equalized and stays a partial vacuum, then the stresses on it are immense  and over time, it will implode,which could take no more than a touch of your hand on it.

In space...the vacuum, as we are told it is will have to be filled by the gases of the rocket, if the rocket could make it...which it couldn't...due to extremely low air pressure so far up into the sky, which would render the rocket a dead stick.

If by some miracle  the rocket could make it...then the gases would simply expand and expand until they filled that vacuum...or should I say...dispersed into it, as nothing could fill it.

Bolded part is wrong, hence the rest of your post is probably relying on a wrong assumption and hence itself is invalid. Fix it and I'll consider giving the scept science another glance.
Title: Re: Space Flight
Post by: iwanttobelieve on June 15, 2013, 01:15:19 AM
but maybe space is not an absolute vacuum.
why do you believe everything you are told scepti?

what Zetetic experiments have you performed?
Title: Re: Space Flight
Post by: iwanttobelieve on June 15, 2013, 01:34:49 AM
but maybe space is not an absolute vacuum.
why do you believe everything you are told scepti?

what Zetetic experiments have you performed?
I don't believe everything I'm told, so what kind of comment is this?
I said, "if space is the vacuum they tell us it is."
The problem still stands about vacuums though.




but the problem is, yes, you do believe what you are told.
you have been force fed that space is an absolute vacuum.

Please list Zetetic experiments that you have performed that give evidence towards this.
Title: Re: Space Flight
Post by: iwanttobelieve on June 15, 2013, 01:57:06 AM
who force fed you that space is an absolute vacuum?
Title: Re: Space Flight
Post by: Shmeggley on June 15, 2013, 05:05:42 AM
If you pressurized a tire in a sealed container at atmo,  what would happen to said tire when taken out of the sealed container?
It would blow the container apart before you got it out. It would just compress the air already inside.
Let me rephrase,  if you were inside a sealed room at atmo, no air in or out , and you filled a tire to the proper pressure; what would happen to the tire when you removed it from the sealed room and exposed it to the atmospheric pressure?
You couldn't do it.

Why?  It should just drop the pressure inside the room a bit too do it,  as well as add a bit more carbon dioxide and other biproducts of the pump.   What makes it impossible?
You couldn't fill the tyre with the proper pressure...it would explode...that's why I'm saying it's impossible.

So, no matter how little air you put in the tire (you brits and your terrible spelling, learn English already ;)) it must explode? What about one molecule of oxygen? That would have to be one strong molecule?!

Obviously one molecule will not have the energy to burst the tire even in a vacuum, nor two, nor three, etc.... Therefore there must be some amount of air that the tire can contain even in a vacuum.
Title: Re: Space Flight
Post by: Rama Set on June 15, 2013, 05:13:39 AM


Quote from: Rama Set
The air would try to expand yes, but the  net pressure it applies would not go up simply because you are in a vacuum.
You have seen a balloon in a vacuum chamber right?
The more air that gets sucked out...the bigger the balloon expands to fill the vacuum and then it pops.
Just like your space rocket would if space is a vacuum and it could reach space.

Space craft are not made from a thin sheet of a highly elastic substance. This makes all the difference in the world.
It makes no difference at all in space, if it's the vacuum we are told.

Of course it would make a difference. An aluminum sheet remains as strong as ever and oxygen can only apply so much force and it is not always going to be enough to cause metal to explode. Unless you can explain metals sudden inability to withstand the outward pressure?
Title: Re: Space Flight
Post by: Shmeggley on June 15, 2013, 05:16:25 AM
but maybe space is not an absolute vacuum.
why do you believe everything you are told scepti?

what Zetetic experiments have you performed?
I don't believe everything I'm told, so what kind of comment is this?
I said, "if space is the vacuum they tell us it is."
The problem still stands about vacuums though.

So if you think "space" is filled with air or some kind of gas, why can't rockets work in space, fly to the moon etc.?
Title: Re: Space Flight
Post by: Scintific Method on June 15, 2013, 05:46:47 AM
The only way I can do this, is to argue it from the point of claims that space is a vacuum.
If it's not...then we are being lied to.
If it is...we are being lied to.

So either way, we're being lied to.

To clarify, space is not a perfect vacuum. A perfect vacuum is a volume of space that contains absolutely no matter, not even a single sub-atomic particle. Space does contain matter, but in miniscule quantities, meaning that it is not a perfect vacuum, but it's close enough for general discussions on the subject.

On another point, do you understand that "psi" is an acronym for "pounds per square inch"? You seem to be confusing it with volume, which would be in cubic inches, cubic feet, gallons, litres, etc.

The larger the chamber...the stronger it has to be, because it has an enormous amount of psi inside it and an enormous amount surrounding the outside of it, equalizing it from inside and out.


This doesn't make a lot of sense. If the chamber is at 0psi inside, and the atmosphere is at 14.7psi outside, then the pressures are clearly not equalised (0 ≠ 14.7). If what you were trying to say was that there is a lot of nothing inside, and a lot of air outside, that would be more correct.

Simply put, a pressure vessel of any kind does not equalise with the surrounding environment, it actually maintains a difference in pressure  between the inside and outside of the vessel. That is the purpose of a pressure vessel. If it did what you suggest, it would be useless, as it would not retain any pressure.
Title: Re: Space Flight
Post by: iwanttobelieve on June 15, 2013, 07:11:11 AM
but maybe space is not an absolute vacuum.
why do you believe everything you are told scepti?

what Zetetic experiments have you performed?
I don't believe everything I'm told, so what kind of comment is this?
I said, "if space is the vacuum they tell us it is."
The problem still stands about vacuums though.

So if you think "space" is filled with air or some kind of gas, why can't rockets work in space, fly to the moon etc.?
I don't know what space is filled with. I can only guess...but we are 'told' it is a vacuum so I dare say that somewhere high up (however high) it make be devoid of matter.

For now, the point of debate, is about rockets and vacuums, right?
So that's what we are dealing with.


Maybe space is not a vacuum. And space travel is possible.
Scepti why do you believe everything NASA tells you?
Title: Re: Space Flight
Post by: DuckDodgers on June 15, 2013, 07:20:47 AM
If you pressurized a tire in a sealed container at atmo,  what would happen to said tire when taken out of the sealed container?
It would blow the container apart before you got it out. It would just compress the air already inside.
Let me rephrase,  if you were inside a sealed room at atmo, no air in or out , and you filled a tire to the proper pressure; what would happen to the tire when you removed it from the sealed room and exposed it to the atmospheric pressure?
You couldn't do it.

Why?  It should just drop the pressure inside the room a bit too do it,  as well as add a bit more carbon dioxide and other biproducts of the pump.   What makes it impossible?
You couldn't fill the tyre with the proper pressure...it would explode...that's why I'm saying it's impossible.

So, no matter how little air you put in the tire (you brits and your terrible spelling, learn English already ;)) it must explode? What about one molecule of oxygen? That would have to be one strong molecule?!

Obviously one molecule will not have the energy to burst the tire even in a vacuum, nor two, nor three, etc.... Therefore there must be some amount of air that the tire can contain even in a vacuum.
The question was about filling the bike tyre to it's normal atmospheric inflation, which would be something like 120/130 psi and that's why my answer was how it was.

I wasn't referring to filling the tire in a vacuum, but just in a sealed room which is at atmospheric pressure, or 14.7 psi.  And car tires, when properly inflated, are in range of 28 to 32 psi typically.  I see absolutely no reason why this tire would not be able to be inflated.  Even so, lets just say you inflate it as much as you can before it pops, lets say 20 psi, what would happen to the tire when it left the sealed room?
Title: Re: Space Flight
Post by: DuckDodgers on June 15, 2013, 07:46:58 AM

Quote from: DuckDodgers
I wasn't referring to filling the tire in a vacuum, but just in a sealed room which is at atmospheric pressure, or 14.7 psi.  And car tires, when properly inflated, are in range of 28 to 32 psi typically.  I see absolutely no reason why this tire would not be able to be inflated.  Even so, lets just say you inflate it as much as you can before it pops, lets say 20 psi, what would happen to the tire when it left the sealed room?
I never inferred that the tire was in a vacuum but you are creating a small vacuum, the minute you start to put air in that tyre in that 'sealed' room that starts off at atmospheric pressure.
The more you put air into the tyre from that atmosphere in that sealed room, that room ceases to become full atmospheric pressure but it wants to become it's normal state, so the air in the tyre expands itself to get into the room to equalize the pressure.

Your tyre will expand and if you open the door to the room, the full atmospheric pressure will rush in and fill the room back to equalized pressure and compress the tire to now equalize the pressure inside of it.

If you get stuck on what I've said, just tell me which part and I'll gladly simplify it.

You are not creating a small vacuum at all just by filling a tire in a filled room.  And I suppose the situation was flawed for what I was trying to get at.  You seem to be implying that the size of the pressure environment around a pressurized container causes the force applied to the vehicle to change.  If you take an object inflated to 30 psi outside and you move it into a room, 10 ft cubed that is sealed off from the outside environment and is at atmo, the force wouldn't change just because the outside environment shrank.  Atmospheric pressure is the same whether in a small cube, a large room, a building, or outside, 14.7 psi is 14.7 psi.  Similarly, a vacuum is the same whether it is in a small cube, large room, a building, or in space, 0 psi is 0 psi.
Title: Re: Space Flight
Post by: hoppy on June 15, 2013, 08:24:04 AM
who force fed you that space is an absolute vacuum?
NASA.
Title: Re: Space Flight
Post by: iwanttobelieve on June 15, 2013, 08:26:47 AM
but Scepti says he is not force fed.  ???
Title: Re: Space Flight
Post by: Antonio on June 15, 2013, 08:49:15 AM
Sceptimatic, in fact you are saying that vacuum is at an infinite negative pressure, right ?
Title: Re: Space Flight
Post by: DuckDodgers on June 15, 2013, 09:23:45 AM
Quote from: DuckDodgers
If you take an object inflated to 30 psi outside and you move it into a room, 10 ft cubed that is sealed off from the outside environment and is at atmo, the force wouldn't change just because the outside environment shrank.  Atmospheric pressure is the same whether in a small cube, a large room, a building, or outside, 14.7 psi is 14.7 psi.  Similarly, a vacuum is the same whether it is in a small cube, large room, a building, or in space, 0 psi is 0 psi.
You are totally missing the point here.

If you inflated a car tyre ,'outside' of the room and then put it in that room, you have simply put it in exactly the same environment as it was outside and all you have done is shut the door, so the tyre would stay exactly how it was when you put it in.
You are confusing yourself.

So the size of the environment doesn't change anything?  Thank you for clarifying that.  Now why can something be placed in a vacuum chamber on Earth and not explode, but would explode out in space?  The pressures of the environment are the exact same, 0 psi.
Title: Re: Space Flight
Post by: iwanttobelieve on June 15, 2013, 11:08:47 AM
Sceptimatic, in fact you are saying that vacuum is at an infinite negative pressure, right ?
If we go by what we are told, then a vacuum is zero pressure or as close as...as to be negative and infinite.
That's what the scientific world would have us believe and they base all their rocketry, etc, on it, so to argue that, we must go by their version of events.
 
Why do you go by what are you are force fed and not Zetism ?
Title: Re: Space Flight
Post by: Antonio on June 15, 2013, 11:21:58 AM
Sceptimatic, in fact you are saying that vacuum is at an infinite negative pressure, right ?
If we go by what we are told, then a vacuum is zero pressure or as close as...as to be negative and infinite.
That's what the scientific world would have us believe and they base all their rocketry, etc, on it, so to argue that, we must go by their version of events.
It's unclear. What do YOU think ? zero pressure or negative and infinite? that's not the same, is it ?
Title: Re: Space Flight
Post by: DuckDodgers on June 15, 2013, 11:46:48 AM
So are you saying that creating a vacuum on Earth is impossible?  And what can we pressurize containers to thousands of psi but we can't contain a pressure differential of 14.7 psi?  Deep sea submersibles have to deal with pressure differentials much, much greater than the 0 psi to 14.7 psi that would exist between atmo and space pressures.  Every 10 meters of ocean depth increases the pressure by 1 atmo, 14.7 psi. 

http://en.wikipedia.org/wiki/Bathyscaphe_Trieste (http://en.wikipedia.org/wiki/Bathyscaphe_Trieste)

This submersible travelled almost 11 km under the ocean.  That is 16,039.17 psi exerting outside the vehicle.  I couldn't find a reference about the internal pressure, but I'm sure it wouldn't be too much higher than atmo at the most, still substantially less than the 16k psi on the outside.  So obviously the 14.7 psi difference sounds quite insubstantial compared to that.
Title: Re: Space Flight
Post by: Antonio on June 15, 2013, 12:52:04 PM
Sceptimatic, in fact you are saying that vacuum is at an infinite negative pressure, right ?
If we go by what we are told, then a vacuum is zero pressure or as close as...as to be negative and infinite.
That's what the scientific world would have us believe and they base all their rocketry, etc, on it, so to argue that, we must go by their version of events.
It's unclear. What do YOU think ? zero pressure or negative and infinite? that's not the same, is it ?
It depends on how you want to twist it.
Let's just go for what we are debating, which is rockets and vacuum.
Sorry, I don't understand what you mean,  I've asked you twice what is the pressure of vacuum, as you should define it before debating about rockets acting on it. It's quite reasonable.

The question is really simple, no tricks, no trap.
Please give me a plain, simple answer.
Title: Re: Space Flight
Post by: DuckDodgers on June 15, 2013, 02:46:46 PM
Firstly, I have an issue with your assumption that there is no way to safely have a container at atmo within a vacuum.
Title: Re: Space Flight
Post by: DuckDodgers on June 15, 2013, 02:59:53 PM
Firstly, I have an issue with your assumption that there is no way to safely have a container at atmo within a vacuum.
I'm going to answer this question with a question first, just so I know how your mindset is on what we are talking about, so I apologise for doing this.

Actually it's two questions.
1. Can you force too much air into a container and explode it?
2.Can you suck too much air out of a container and implode it?
How you answer these, will determine if you are grasping anything I've put forward.
These are very incomplete questions, but very well.
1.  Yes
2.  Yes
However, the design of the container will dictate whether and when they explode/implode.
Title: Re: Space Flight
Post by: Rama Set on June 15, 2013, 03:15:54 PM
Firstly, I have an issue with your assumption that there is no way to safely have a container at atmo within a vacuum.
I'm going to answer this question with a question first, just so I know how your mindset is on what we are talking about, so I apologise for doing this.

Actually it's two questions.
1. Can you force too much air into a container and explode it?
2.Can you suck too much air out of a container and implode it?
How you answer these, will determine if you are grasping anything I've put forward.
These are very incomplete questions, but very well.
1.  Yes
2.  Yes
However, the design of the container will dictate whether and when they explode/implode.
Great stuff'
At least you are getting there a little bit.
Just to be a bit more clear with you. They could use any design they wanted and any thickness, but if you attempt to suck out more air than it can handle, then it implodes and if you put too much air pressure in, it will explode, do you agree with this before I go on...and if not, tell me why not, in very simple terms.

As long as you understand the difference between a vacuum and negative air pressure.
Title: Re: Space Flight
Post by: Scintific Method on June 15, 2013, 03:37:27 PM
1. Can you force too much air into a container and explode it?
2.Can you suck too much air out of a container and implode it?

If I may, I'll submit my answers as well:

1. Yes, always, the limit depends only on the design of the container
2. Not necessarily. If the container is weak, yes, but if it has been designed to withstand the difference between atmospheric 14.7psi and vacuum 0psi, then no. Btw, designing for this is not hard, as I pointed out earlier, light bulbs often use a near-total vacuum to stop the filament burning up.
Title: Re: Space Flight
Post by: Scintific Method on June 15, 2013, 04:52:30 PM
1. Can you force too much air into a container and explode it?
2.Can you suck too much air out of a container and implode it?

If I may, I'll submit my answers as well:

1. Yes, always, the limit depends only on the design of the container
2. Not necessarily. If the container is weak, yes, but if it has been designed to withstand the difference between atmospheric 14.7psi and vacuum 0psi, then no. Btw, designing for this is not hard, as I pointed out earlier, light bulbs often use a near-total vacuum to stop the filament burning up.
You still fail to understand how atmospheric pressure works.
Oh and light bulbs are filled with an inert gas.

One of us certainly fails to understand pressure, and given that I have done numerous experiments involving pressure differences and vacuums, I think I know who it is...

As for light bulbs, here's a quote from a Wikipedia article on them:

Quote
"The hot filament is protected from oxidation with a glass bulb that is filled with inert gas (or evacuated)."

Evacuated means a vacuum has been created inside the bulb. We are both correct on this, although you imply they are all filled with inert gas, whereas I allow that only some use a vacuum. The ones using a vacuum are the ones that make a loud 'pop' when broken.

Oh, and I don't think you ever answered my question about the mercury barometer. What is in that empty space at the top? It's not air, and it's not mercury, so what is it?
Title: Re: Space Flight
Post by: DuckDodgers on June 15, 2013, 06:10:31 PM
Firstly, I have an issue with your assumption that there is no way to safely have a container at atmo within a vacuum.
I'm going to answer this question with a question first, just so I know how your mindset is on what we are talking about, so I apologise for doing this.

Actually it's two questions.
1. Can you force too much air into a container and explode it?
2.Can you suck too much air out of a container and implode it?
How you answer these, will determine if you are grasping anything I've put forward.
These are very incomplete questions, but very well.
1.  Yes
2.  Yes
However, the design of the container will dictate whether and when they explode/implode.
Great stuff'
At least you are getting there a little bit.
Just to be a bit more clear with you. They could use any design they wanted and any thickness, but if you attempt to suck out more air than it can handle, then it implodes and if you put too much air pressure in, it will explode, do you agree with this before I go on...and if not, tell me why not, in very simple terms.

Any container is only as strong as its design.   Once the design limit is exceeded,  it fails. 
Title: Re: Space Flight
Post by: Scintific Method on June 15, 2013, 09:40:21 PM
Quote from: Scintific Method

Oh, and I don't think you ever answered my question about the mercury barometer. What is in that empty space at the top? It's not air, and it's not mercury, so what is it?
It's a partial vacuum.
I fail to see what you are getting at.

Partial vacuum? So what's in that space that makes it only a partial vacuum?
What I'm getting at is that that space is, essentially, the same level of vacuum as space. It's only a small volume, but it is still a vacuum. What you have been saying, as far as I can tell, is that the top of the tube should collapse violently under atmospheric pressure, and yet it doesn't.

I know you know about air pressures, I'll give you that.
All I'm saying , with all due respect to you...is...you are missing some crucial thinking about it, which is the reason we cannot agree on it.
I'm not trying to be smug here but I also know what I'm talking about...but let's not get into a dick measuring contest and we can get to the bottom of the problem, so we are both clear. Ok?

Would you say that the crucial thinking I'm missing is the volumes involved? I am well aware of the volumes involved, but I am also aware that they do not really make much of a difference. A billion cubic miles of air at 14.7psi applies the same amount of pressure to something as a single cubic inch of air at 14.7psi. Note I said pressure, not force. The force applied depends entirely on the surface area of the object.

I'm not trying to be a smart-arse, I'm just trying to explain things as I understand them.
Title: Re: Space Flight
Post by: DuckDodgers on June 15, 2013, 09:42:58 PM
So now you know that they can all be breached, it's just a matter of pressure from outside or inside a vessel.

So bearing that in mind...and the fact that we are talking about rockets in the vacuum of space as we are constantly reminded that space is...you should now be clear in your mind that any rocket carrying fuel into that vacuum, will be rendered useless in short order, because it will surrender its gases to that vacuum 'unconditionally.'

Except rockets are specifically designed to function in a vacuum.  You are putting far too little faith in human ingenuity.  I can't begin to tell you how a rocket engine actually functions, but I can telling you that like any other engine, fuel flow rate plays a major part in its workings.  I would also imagine that the exhaust area of the rocket would be the most resiliently designed portion of the rocket to counter the fact that it is a designed exit for matter.
Title: Re: Space Flight
Post by: Antonio on June 15, 2013, 10:36:06 PM
Sceptimatic, in fact you are saying that vacuum is at an infinite negative pressure, right ?
If we go by what we are told, then a vacuum is zero pressure or as close as...as to be negative and infinite.
That's what the scientific world would have us believe and they base all their rocketry, etc, on it, so to argue that, we must go by their version of events.
It's unclear. What do YOU think ? zero pressure or negative and infinite? that's not the same, is it ?
It depends on how you want to twist it.
Let's just go for what we are debating, which is rockets and vacuum.
Sorry, I don't understand what you mean,  I've asked you twice what is the pressure of vacuum, as you should define it before debating about rockets acting on it. It's quite reasonable.

The question is really simple, no tricks, no trap.
Please give me a plain, simple answer.
And like I've told you...to make it simple...let's go with 'zero' psi.
You started saying  maybe zero maybe negative. Anyway, why quoting 'zero' ? It's a bit difficult to have some clear answers here.
I insist on this because it's the main point. Should we go now further with your assumption of a real zero pressure vacuum, without quotes, or you think that this zero psi has something special ?
Please keep it plain and simple.
Title: Re: Space Flight
Post by: hoppy on June 16, 2013, 04:41:17 AM

Quote from: Scintific Method
Partial vacuum? So what's in that space that makes it only a partial vacuum?

This is an excellent question...one of which I've been waiting to answer and as to why people underestimate, atmospheric pressure.
The reason it's only a partial vacuum, is, because not all of the air has been taken out....some is left in which expands to equalise the outside pressure, which because the vacuum itself was solely created by the mercury's weight, it's weight is not strong enough to create a full vacuum. If you don't understand this... tell me why and I'll be glad to explain.
What is in the top of the mercury tube if not a vacuum?
Title: Re: Space Flight
Post by: Scintific Method on June 16, 2013, 06:16:29 AM
Quote from: Scintific Method
Partial vacuum? So what's in that space that makes it only a partial vacuum?

This is an excellent question...one of which I've been waiting to answer and as to why people underestimate, atmospheric pressure.
The reason it's only a partial vacuum, is, because not all of the air has been taken out....some is left in which expands to equalise the outside pressure, which because the vacuum itself was solely created by the mercury's weight, it's weight is not strong enough to create a full vacuum. If you don't understand this... tell me why and I'll be glad to explain.

But all the air was driven out when the mercury filled the tube, there can be none left.

Oh, and if you take 1 cubic inch of air at 14.7psi and expand it to fill 10 cubic inches of space (not hard to do, a similar thing can be done with a cheap medical syringe by blocking the end with your finger and pulling the plunger back), it won't stay at 14.7psi unless you add a lot of energy to it! What you will end up with if all you do is expand the air, is 10 cubic inches of air at 1.47psi (please note the decimal point).

Quote from: Scintific Method
What I'm getting at is that that space is, essentially, the same level of vacuum as space. It's only a small volume, but it is still a vacuum. What you have been saying, as far as I can tell, is that the top of the tube should collapse violently under atmospheric pressure, and yet it doesn't.

It will only implode, if more air is taken from it.
Under just the weight of the mercury itself, which created that partial vacuum...the tube is well strong enough to withstand outside air pressure against it.

Say I have a really long tube, and a deep container of mercury. When I lift that tube 30 inches out of the mercury, the mercury stops rising with the tube and stays at 30 inches (well, 29.9 at sea level on an ICAO standard day). If I continue to lift the tube, that empty space gets bigger and bigger, but the tube won't break. Why?

Quote from: Scintific Method
Would you say that the crucial thinking I'm missing is the volumes involved? I am well aware of the volumes involved, but I am also aware that they do not really make much of a difference. A billion cubic miles of air at 14.7psi applies the same amount of pressure to something as a single cubic inch of air at 14.7psi. Note I said pressure, not force. The force applied depends entirely on the surface area of the object.

I'm not trying to be a smart-arse, I'm just trying to explain things as I understand them.
This is where you are going wrong. You see,  we , as humans with our small frames against the amount of air pressure in volume around us, can happily survive in it, because we equalize that pressure fairly easily as long as we stay strong enough to withstand it.
Trust me...air pressure can be complicated for many people to logically get their heads around, because they only think of it in basically irrelevant thoughts...such as, ' oh, it's nothing, we can run in it and breathe it, so it's no big deal.'
Which it isn't, in that context.
It starts to become more difficult to understand when you start to mess with it's natural atmospheric density...this is where people lose track of it.
If you want a one on one explanation, I'd be happy to give you one and I'm not being smug...I really do know what I'm talking about on this.

Pressure is pressure, 14.7psi means there is 14.7 pounds of force being applied to every square inch of a surface exposed to it. Makes no difference how much air is pushing on that surface, it's still only pushing with a force of 14.7psi.

If I am missing something, please do point it out.
Title: Re: Space Flight
Post by: markjo on June 16, 2013, 07:27:05 AM

Quote from: Stabbald
Half of your argument relies on the made up "fact" that anything sent into space will instantly explode due to the vacuum. This is *impossible* unless the pressure of space is vastly negative, which it isn't. It's been demonstrated to you repeatedly that things have already been built that can withstand pressure differentials orders of magnitude higher.
Any rocket sent into a zero psi vacuum will 'expand' all of it's fuel, 'immediately' into that vacuum.Any pressure against zero pressure as in a virtual vacuum, will 'always' attempt to equalize that pressure.
The rocket, will be breached due to expanded gases against no resistance.
Actually, the fuel and oxidizer in most space rockets are stored in a liquid form and pumped into into the rocket engine's combustion chamber where they are converted into gasses and burned.
Title: Re: Space Flight
Post by: Shmeggley on June 16, 2013, 08:41:12 AM

Quote from: Scintific Method
Partial vacuum? So what's in that space that makes it only a partial vacuum?

This is an excellent question...one of which I've been waiting to answer and as to why people underestimate, atmospheric pressure.
The reason it's only a partial vacuum, is, because not all of the air has been taken out....some is left in which expands to equalise the outside pressure, which because the vacuum itself was solely created by the mercury's weight, it's weight is not strong enough to create a full vacuum. If you don't understand this... tell me why and I'll be glad to explain.
What is in the top of the mercury tube if not a vacuum?

Maybe some mercury vapor?
Title: Re: Space Flight
Post by: Antonio on June 16, 2013, 08:58:00 AM

Quote from: Antonio
I insist on this because it's the main point. Should we go now further with your assumption of a real zero pressure vacuum, without quotes, or you think that this zero psi has something special ?
Please keep it plain and simple.
If you want to keep things simple, then stop the twisting. You clearly know I'm talking about a vacuum and it couldn't be any clearer throughout this topic...so to be simple...we are talking about a vacuum, ok?
Well actually you are twisting simple things. I'm just asking you to clearly define vacuum, as it seems that you have a personal definition for it. Nothing more, nothing less. I understand that you are under heavy crossfire and immediately light your defense mode, but you are constantly avoiding the answer.

You often say "be open minded, don't be spoonfed".  I agree, and thence cannot blindly believe your theories just because you say "I'm right" ? So please go forward:
Is you definition of vacuum at a zero pressure state? If no, please explain, if yes, let's go to the following step.

Simple.
Title: Re: Space Flight
Post by: 29silhouette on June 16, 2013, 09:17:57 AM
Any rocket sent into a zero psi vacuum will 'expand' all of it's fuel, 'immediately' into that vacuum.Any pressure against zero pressure as in a virtual vacuum, will 'always' attempt to equalize that pressure.
The rocket, will be breached due to expanded gases against no resistance.
A rocket engine that works or doesn't blow up in a zero pressure/vacuum chamber on Earth will work in a zero pressure/vacuum in space.

Newtons third law is fine , on earth. It won't do jack shit in the vacuum of outer space.

Read this explanation (http://www.straightdope.com/columns/read/1846/how-do-rockets-work-in-the-vacuum-of-space)
This explanation from the dope, is fine on earth...but it still requires friction to happen...something the rocket will have none of in a vacuum.
And once again, pressure against the inside of the combustion chamber and nozzle pushes the rocket.
Title: Re: Space Flight
Post by: spaceman spiff on June 16, 2013, 09:53:48 AM
What is this "partial vacuum"? I think you want to say "almost vacuum", otherwise it makes absolutely no sense at all.
Title: Re: Space Flight
Post by: hoppy on June 16, 2013, 11:36:31 AM
Scepti, how long have you had this knowledge of vacuums and 0 pressure? I can see your theories  are possibly correct, but we are going against rocket scientists and every other wanttobe. The railroad tanker car imploding from vacuum pressure was impressive. Did you develope these theories yourself or have you learned of the power of a vacuum from someone else.
Title: Re: Space Flight
Post by: iwanttobelieve on June 16, 2013, 01:15:59 PM
believe me, hoppy has more faith than any member   here. 

Why Scepti do you believe everything NASA has force fed you?
You really need to learn Zetetic Reasoning.
It will bring you enlightenment.
Title: Re: Space Flight
Post by: hoppy on June 16, 2013, 02:01:32 PM
Scepti, how long have you had this knowledge of vacuums and 0 pressure? I can see your theories  are possibly correct, but we are going against rocket scientists and every other wanttobe. The railroad tanker car imploding from vacuum pressure was impressive. Did you develope these theories yourself or have you learned of the power of a vacuum from someone else.
I've had the knowledge for a long time, Hoppy.

I know how easily people are duped...and it's not because they are unintelligent...in fact, the opposite. Sometimes they are too intelligent, that they have studied so much into the lies...they cannot accept that their work has in some parts, been nothing other than memorised garbage, passed off as reality.
If some could open their minds and see past this...they would stand a much greater chance of realising that they studied the easy route by being blinded by past, 'supposed' geniuses, that were mostly just fantasy thinkers and guess work artists.
Scepti, pay no attention to the idiot iwtb. Can you speak on the bolded part of my last question?
Title: Re: Space Flight
Post by: Scintific Method on June 16, 2013, 04:45:27 PM
Quote from: Scintific Method
But all the air was driven out when the mercury filled the tube, there can be none left.
If all the air was driven out, the barometer would not work.
Here's a clue. What does a barometer measure?

Air pressure. Nice job of twisting that to make you look right, but a more pertinent question would be how does it measure air pressure? It measures it against an absolute reference point. What is the only absolute reference point when it comes to pressure? Yep, 0, a vacuum.

Quote from: Scintific Method
Oh, and if you take 1 cubic inch of air at 14.7psi and expand it to fill 10 cubic inches of space (not hard to do, a similar thing can be done with a cheap medical syringe by blocking the end with your finger and pulling the plunger back), it won't stay at 14.7psi unless you add a lot of energy to it! What you will end up with if all you do is expand the air, is 10 cubic inches of air at 1.47psi (please note the decimal point).
Go and suck the water out of a plastic water bottle...see how much you can suck out before you get tired, then put your tongue over the bottle top and see how long your tongue muscles can hold before the  vacuum wants it inside of it. This will give you an idea of what you are dealing with...If you try this...you will also notice that your pop bottle is crushed.

I wasn't using a plastic bottle as my example though, because they do not withstand compression forces at all. They are, however, very good at containing tension forces caused by the fluid inside being at higher pressure than the outside environment. Try it the way I described, with a syringe. You will need one with a rubber plunger seal though, the ones without seals leak too much.

Quote from: Scintific Method
Say I have a really long tube, and a deep container of mercury. When I lift that tube 30 inches out of the mercury, the mercury stops rising with the tube and stays at 30 inches (well, 29.9 at sea level on an ICAO standard day). If I continue to lift the tube, that empty space gets bigger and bigger, but the tube won't break. Why?
Because the weight of the mercury cannot create a full vacuum, it can only create a partial vacuum in relation to the downward force of its weight. If you want to call it gravity, then go ahead.

So, what you're saying is, if I lift the tube high enough, the low pressure on top will eventually become too much for the mercury and start to lift it? Problem with that is, a mercury column will only ever rise as high as 30 inches at sea level, no matter how tall the tube.

Quote from: Scintific Method
Pressure is pressure, 14.7psi means there is 14.7 pounds of force being applied to every square inch of a surface exposed to it. Makes no difference how much air is pushing on that surface, it's still only pushing with a force of 14.7psi.

If I am missing something, please do point it out.
Yes, you are missing a very important point.
Air has to equalise its pressure when any pressure is lowered or gained, against it.
If the pressure is lowered, as in a vacuum chamber, the outside air pressure will try to equalize that pressure.

Right so far, but the chamber walls create a physical barrier and maintain the differential through the strength of their design.

For instance:
If I take out 6 psi from a chamber, making it a partial vacuum...what I have done, is lowered the air pressure inside of it, so it wants to get out, because the molecules are all agitated.
It's this agitation that is trying to expand the chamber.

I think you got that the wrong way around. If you lower the internal pressure, there is less air inside, and it is actually less agitated than before, so it's not trying to expand the chamber, it's trying to collapse it.

The atmospheric pressure also wants to equalize the pressure so it will exert its full force onto the chamber...but the chamber is built strongly and can hold it back.

Exactly right, and there are chambers built to withstand the full force of atmospheric pressure outside and vacuum inside.

You start to take more air out ...more than the chamber is designed to allow and the remaining air inside it, will expand more to keep trying to equalise the pressure from outside, whilst the pressure from outside, exerts more force to to equalise that...and so on, until the chamber, implodes.

Unless it's designed to cope with a vacuum inside it, which many are.

An example, is to look at a partially filled balloon inside a vacuum chamber and watch it expand and expand, as more air is taken for it.
The balloon will fill up until it bursts, because the air inside of it wants to equalise the air that is getting sucked out.

Unless you don't put too much air in to start with, then it will just expand until the elastic tension of the balloon equalises with the pressure inside it. Much like a tension spring only extends so far when you put a certain amount of weight on it.

Any questions and I'll be glad to help.

If you can give me a convincing reason why all of what I just said is wrong, go for it, but it must be convincing. Experiments that I can do that actually tell me something useful would help.
Title: Re: Space Flight
Post by: Antonio on June 17, 2013, 12:19:01 AM

Quote from: Antonio
I insist on this because it's the main point. Should we go now further with your assumption of a real zero pressure vacuum, without quotes, or you think that this zero psi has something special ?
Please keep it plain and simple.
If you want to keep things simple, then stop the twisting. You clearly know I'm talking about a vacuum and it couldn't be any clearer throughout this topic...so to be simple...we are talking about a vacuum, ok?
Well actually you are twisting simple things. I'm just asking you to clearly define vacuum, as it seems that you have a personal definition for it. Nothing more, nothing less. I understand that you are under heavy crossfire and immediately light your defense mode, but you are constantly avoiding the answer.

You often say "be open minded, don't be spoonfed".  I agree, and thence cannot blindly believe your theories just because you say "I'm right" ? So please go forward:
Is you definition of vacuum at a zero pressure state? If no, please explain, if yes, let's go to the following step.

Simple.
Let's make this really simple for you.
Go and look up what is officially said, space is and you can use that as your yardstick.
So should we agree that vacuum has a pression of 0psi ?
Should we also agree that a pressure is a force divided by a surface ?
Title: Re: Space Flight
Post by: SuperHater7810 on June 17, 2013, 03:29:22 AM
The air inside the can gets hot, expands so the presdure invreases.
It wants to escape to an aria of lower pressure. The lid is blown off as
The gas rsvapes as that is the weakist point.
Its not a vaccum where dealing with here its the opposite of that.
Title: Re: Space Flight
Post by: Scintific Method on June 17, 2013, 05:08:36 AM
Think of high pressure, or dense pressure as a crowd of people in a tube train squashing each other and more people getting on at the next stop, creating an even denser crowd pushing against the train walls.
Well this is your compressed air...which isn't what we are dealing with here but it helps to differentiate.
Now think of low pressure as a lot less people on that train bumping into each other as they all try to find an exit, so they all start running at the walls to get out, yet they can't get out because the walls are too strong..but they keep running at them and banging on them to try to weaken it, whilst a massive dense crowd outside is clamped against it.
Any problems with this and I'll be glad to answer them.

Yes, I have a big problem with this. Pressure is created by molecules of a fluid impacting on a surface. Low pressure is created either by reducing the number of molecules without changing the energy level (temperature), lowering the energy level without removing any molecules, or a combination of both. I'm assuming a fixed volume for the sake of simplicity, although increasing volume without changing any other factors also reduces pressure.

With your crowd example, this means that when some of the people get off the train, the rest just keep moving about at the same speed as they were before, bumping into the walls with the same individual force as before, but since there are now less of them, their total force (the pressure) is reduced. The way you worded your analogy would be the equivalent of removing some of the air, then heating the rest up so that the pressure actually increased. By heating the remaining air, you add energy, so the molecules move more quickly and impact on the walls with more individual force.

Thinking like this, a vacuum is like a train with only one or two people in it, ambling about and only rarely bumping into the walls. This is actually a useful analogy, as even a pretty large crowd pressing on the outside of the train would not be able to collapse it, even if there were no-one inside. Of course, at some point there will be enough people outside to crush the train, and that would be equivalent to sending an evacuated vacuum chamber to the bottom of the ocean.

Quote from: Scintific Method
Unless you don't put too much air in to start with, then it will just expand until the elastic tension of the balloon equalises with the pressure inside it. Much like a tension spring only extends so far when you put a certain amount of weight on it.

The balloon will expand until it explodes or fills the inside walls of the vacuum chamber and if it's elastic enough, it will expand against it, harder and harder until it explodes and releasing its expanded air into the chamber to be nano second immediately forced into the atmosphere whether through the pump or by implosion of that chamber...whichever happens first.
On earth...atmospheric pressure win 'every time' against a complete vacuum.
Any questions and I'll be glad to help.

Have you tried this yet? I think you really should find someone willing to let you put a barely-inflated balloon in a vacuum chamber and see what happens when the chamber is evacuated.

Quote from: Scintific Method
If you can give me a convincing reason why all of what I just said is wrong, go for it, but it must be convincing. Experiments that I can do that actually tell me something useful would help.

Go and put an empty paint can on a fire, with a tight lid on and watch the lid blow off after a few minutes.
Why do you think this happens?

Adding heat energy to the can excites the air molecules inside, causing the pressure to rise in accordance with Gay-Lussac's law, eventually exceeding the pressure required to dislodge the lid of the can, allowing the heated gas to escape explosively. Nothing revolutionary about that, it was worked out 200 years ago. Try again.
Title: Re: Space Flight
Post by: Puttah on June 17, 2013, 07:45:59 AM
]I have to give credit to my uncle for explaining it.

And where did your uncle find out that pressure works differently to how mainstream science claims it does? If the answer turns out to be that he found out from a friend of a friend of his, where did that person get the info? etc. etc.

In the end, it all comes down to experimentation, and you're seriously lacking in that regard.
Title: Re: Space Flight
Post by: Antonio on June 17, 2013, 07:58:48 AM
Quote
Oh...and I didn't answer the other parts, because it was starting to get tedious.
Well, you are depicting your vision of reality, claiming everywhere "truth, truth", but fail to explain it at a very basic level. Fine enough, go with it, but don't expect people to follow you in this path.
Title: Re: Space Flight
Post by: DuckDodgers on June 17, 2013, 08:07:52 AM
Quote
Oh...and I didn't answer the other parts, because it was starting to get tedious.
Well, you are depicting your vision of reality, claiming everywhere "truth, truth", but fail to explain it at a very basic level. Fine enough, go with it, but don't expect people to follow you in this path.
I don't expect anyone to follow it. That's entirely up to them.
As I said earlier. I've explained it enough to give genuine people a chance to have a real good think about how easily Newtons laws can be used to dupe people.
Just going to throw this out,  but you haven't much to show the laws of motion being used to dupe the masses besides simply question their application.   You have yet to show a definitive fact that rockets do not move due to the laws of motion alone,  opposing forces and such. 
Title: Re: Space Flight
Post by: markjo on June 17, 2013, 08:08:06 AM
You keep talking about rockets as though they will explode as soon as they reach a vacuum due to the atmosphere inside of them. The difference in pressure is 14.7 psi.
I wonder if Sceptimatic is interpreting the pressure differential as 14.7 psi atmospheric pressure divided by 0 psi vacuum pressure resulting in an infinite pressure difference.
Title: Re: Space Flight
Post by: SuperHater7810 on June 17, 2013, 08:10:42 AM


 The reason I used this example , if you can see past what I'm about to say, which I won;t hold my breath about...is:
The water molecules, in that dense air, turn to gas and expand inside the tin...but outside the tin, is a raging fire, which is consuming all of the oxygen and creating a partial vacuum around it, meaning there is very little air pushing against the outside of the can, which means that the longer the fire burns...the more that the can expands...blowing off the top, or the weakest point.

Picture the fire around the can...as the vacuum of space...
Note: I know space isn't fire....I'm saying, picture the fire around the can, as the consumption of air, as in a vacuum and you should see why a rocket would not work in a vacuum...but I know you won't.

Oh...and I didn't answer the other parts, because it was starting to get tedious.

Well the fire wouldn't create much of a vacuum. Any gas that it consumed would just be replaced by gasses from other parts of the room. But i can see that that's sort of besides the point.
If we where to weld the lid of the tin in place or find some other way to securely fasten it in place, we could make the tin stand up to the differences in pressure. and the lid would likely stay firmly in place.
Just like how they design space craft to stand up to the differences of pressure in space.
Title: Re: Space Flight
Post by: markjo on June 17, 2013, 08:40:41 AM
You keep talking about rockets as though they will explode as soon as they reach a vacuum due to the atmosphere inside of them. The difference in pressure is 14.7 psi.
I wonder if Sceptimatic is interpreting the pressure differential as 14.7 psi atmospheric pressure divided by 0 psi vacuum pressure resulting in an infinite pressure difference.
Nope.
Then how do you explain the infinite pressure of a vacuum?
Title: Re: Space Flight
Post by: Antonio on June 17, 2013, 08:48:36 AM
Quote
Oh...and I didn't answer the other parts, because it was starting to get tedious.
Well, you are depicting your vision of reality, claiming everywhere "truth, truth", but fail to explain it at a very basic level. Fine enough, go with it, but don't expect people to follow you in this path.
I don't expect anyone to follow it. That's entirely up to them.
As I said earlier. I've explained it enough to give genuine people a chance to have a real good think about how easily Newtons laws can be used to dupe people.
By genuine people you mean people who will accept your theories just because you say they are right? . What difference with "NASA  bullshit" ?
Well, it gives you some guru rank now... ::)
Title: Re: Space Flight
Post by: Puttah on June 17, 2013, 08:56:44 AM
]I have to give credit to my uncle for explaining it.

And where did your uncle find out that pressure works differently to how mainstream science claims it does? If the answer turns out to be that he found out from a friend of a friend of his, where did that person get the info? etc. etc.

In the end, it all comes down to experimentation, and you're seriously lacking in that regard.
If this is all you have to say, then your input is irrelevant to me.
I don't give a rats arse whether you accept what I say or not. I think we both know where your feet are firmly planted.
There is , however...plenty of people looking at this with an open and more scrutinising mind, who can and will, see past the dis-info.

How am I not surprised that you once again dodge my question.

Anyway, I don't care to force an answer out of you that'll fail to help you realize that your theories are baseless, I just wanted to pick fun at your hilarious reference  ;D
Title: Re: Space Flight
Post by: Rama Set on June 17, 2013, 09:01:59 AM
You really do not understand that the inside of the rocket does not exert extra force from the interior pressure once it enters a vacuum?  The pressure exerted on the exterior if the craft will only rise by 14.7 psi, and this will be a gradual, not a dynamic change. This pressure differential although it can never equalize, can easily be engineered for.
Title: Re: Space Flight
Post by: hoppy on June 17, 2013, 09:02:16 AM
You keep talking about rockets as though they will explode as soon as they reach a vacuum due to the atmosphere inside of them. The difference in pressure is 14.7 psi.
I wonder if Sceptimatic is interpreting the pressure differential as 14.7 psi atmospheric pressure divided by 0 psi vacuum pressure resulting in an infinite pressure difference.
Did you see the video of the steel tank railroad car inplode due to 14.7 psi differential?
Title: Re: Space Flight
Post by: Puttah on June 17, 2013, 09:07:19 AM

Quote from: Puttah
How am I not surprised that you once again dodge my question.

Anyway, I don't care to force an answer out of you that'll fail to help you realize that your theories are baseless, I just wanted to pick fun at your hilarious reference  ;D
Keep smiling, kid.
Keep it together grandpa.
Title: Re: Space Flight
Post by: Antonio on June 17, 2013, 09:11:38 AM
Ok, let's go again.
Do you agree that a pressure is a force divided by a surface ?
Title: Re: Space Flight
Post by: Rama Set on June 17, 2013, 09:16:38 AM
You really do not understand that the inside of the rocket does not exert extra force from the interior pressure once it enters a vacuum?  The pressure exerted on the exterior if the craft will only rise by 14.7 psi, and this will be a gradual, not a dynamic change. This pressure differential although it can never equalize, can easily be engineered for.
There is no force on the exterior of the ship...it's in a zero psi environment.
The rockets stress is entirely inside of it, in fuel,life support...and anything holding liquid or air molecules.
All of this will be expanded from that ship UNCONDITIONALLY into that vacuum.
All the vacuum does, is wait for it, because the pressure inside needs to equalise.
And it will attempt to, because it's under no resistant force.

I understand what you are saying, but what I would like to know is why a container cannot withstand the pressure differential?
Title: Re: Space Flight
Post by: markjo on June 17, 2013, 09:49:48 AM
You keep talking about rockets as though they will explode as soon as they reach a vacuum due to the atmosphere inside of them. The difference in pressure is 14.7 psi.
I wonder if Sceptimatic is interpreting the pressure differential as 14.7 psi atmospheric pressure divided by 0 psi vacuum pressure resulting in an infinite pressure difference.
Did you see the video of the steel tank railroad car inplode due to 14.7 psi differential?
Was the steel tank railroad car designed to withstand a 14.7 psi differential?
Title: Re: Space Flight
Post by: DuckDodgers on June 17, 2013, 10:16:53 AM
You keep talking about rockets as though they will explode as soon as they reach a vacuum due to the atmosphere inside of them. The difference in pressure is 14.7 psi.
I wonder if Sceptimatic is interpreting the pressure differential as 14.7 psi atmospheric pressure divided by 0 psi vacuum pressure resulting in an infinite pressure difference.
Did you see the video of the steel tank railroad car inplode due to 14.7 psi differential?
Was the steel tank railroad car designed to withstand a 14.7 psi differential?
It's likely designed for more than that,  but it's designed for higher internal pressure would be my guess.
Title: Re: Space Flight
Post by: DuckDodgers on June 17, 2013, 10:24:31 AM
You really do not understand that the inside of the rocket does not exert extra force from the interior pressure once it enters a vacuum?  The pressure exerted on the exterior if the craft will only rise by 14.7 psi, and this will be a gradual, not a dynamic change. This pressure differential although it can never equalize, can easily be engineered for.
There is no force on the exterior of the ship...it's in a zero psi environment.
The rockets stress is entirely inside of it, in fuel,life support...and anything holding liquid or air molecules.
All of this will be expanded from that ship UNCONDITIONALLY into that vacuum.
All the vacuum does, is wait for it, because the pressure inside needs to equalise.
And it will attempt to, because it's under no resistant force.

I understand what you are saying, but what I would like to know is why a container cannot withstand the pressure differential?
Air pressure has mass right?
It has weight.
On earth, at sea level... air pressure is at 14.7 psi.
If you were to climb mount Everest, you would get so far up and the air would get thinner and your breathing will suffer, because your lungs are designed for the pressure environment you live in and you are getting out of that comfort zone.
To acclimatise, you need to suck in harder by EXPANDING your lungs to get the air you need....yet if you go higher, you will need to oxygenate your blood by using breathing apparatus.

Now this is only at 35,000 feet or so.

Now imagine taking up a balloon that's virtually flat but tied at sea level with a little bit of air inside it.
You take that up the mountain and you'll find that it's inflated slightly due to there being less air and the air inside the balloon will expand to equalise that, no matter what...so every footstep taken above that, if Everest grew as you walked and you were superman who didn't give a shit about air pressure lol...then that balloon will very slowly, keep expanding  all the way up, until the inevitable happens and it goes pop.

So remembering that air , will always expand all the way up to equalise the environment it finds itself in.
Put that inside  a rocket and your rocket would give up it's gases to the vacuum of zero psi as it HAS to equalise the pressure.

Do you even read your posts?  Air pressure has no mass or weight as it is created by the mass of the air itself.   It isn't the air pressure at altitude that is the problem,  but what causes the lower pressure that is the problem,  which is less air and less oxygen because of this.
You're essentially correct in your statement that pressures want to equalize,  however you are incorrect in that containers have been designed to withstand this effect through only their material and design,  some likely use the outside pressure to aid this,  but not all do.
Title: Re: Space Flight
Post by: DuckDodgers on June 17, 2013, 10:49:33 AM

Quote from: DuckDodgers
Do you even read your posts?  Air pressure has no mass or weight as it is created by the mass of the air itself.

So air pressure has no mass or weight. Oh ok then, that's that sorted.
Think about what you are saying.
Does a crowd of people laid on top of each other have mass and weight?

Quote from: DuckDodgers
It isn't the air pressure at altitude that is the problem,  but what causes the lower pressure that is the problem,  which is less air and less oxygen because of this.

You say it isn't the air pressure at altitude that is the problem.
It's called less air pressure, meaning less molecules of air.


Quote from: DuckDodgers
You're essentially correct in your statement that pressures want to equalize,  however you are incorrect in that containers have been designed to withstand this effect through only their material and design,  some likely use the outside pressure to aid this,  but not all do.

It's the outside pressure that vacuum chambers are designed to deflect.
How about you read my statement again.   Pressure is an effect of volume, mass,  and temperature; thus pressure cannot have a distinct weight to it.   Air pressure is literally to weight of the atmosphere pressing down on you,  keywords being weight of the atmosphere.   Less air molecules means less pressure,  but less pressure doesn't mean less air molecules,  it could also be cooler or in a larger volume but have the exact same mass.   Again,  pressure is an effect and not a cause.
Title: Re: Space Flight
Post by: markjo on June 17, 2013, 10:55:34 AM
The atmosphere will crush ANYTHING no matter how strong it is, if more air gets evacuated from any container of any size or thickness.
This is the part where we just can't seem to agree.  The examples that you give of things that implode under a vacuum are things that aren't designed to handle a vacuum.  Sure, it may seem like common sense that nature abhors a vacuum and wants to fill that empty space, but engineers go out of their way to defy common sense and make pressure vessels that can resist the tremendous forces involved when working with vacuums.
Title: Re: Space Flight
Post by: Antonio on June 17, 2013, 11:09:47 AM
Ok, let's go again.
Do you agree that a pressure is a force divided by a surface ?
Carry on and get to the point.
Once again, as you seem to have a different definition, can you just simply and directly answer to a basic, simple question?
The answer IS the point. I can even ask in another way, what "psi" stands for ?
Title: Re: Space Flight
Post by: Antonio on June 17, 2013, 11:47:04 AM
 ;D
no, I said psi not P.S.I.
Title: Re: Space Flight
Post by: Shmeggley on June 17, 2013, 11:48:55 AM

Quote from: markjo
Was the steel tank railroad car designed to withstand a 14.7 psi differential?
The answer is obviously, no.
The reason for this, is because it imploded.
The atmosphere will crush ANYTHING no matter how strong it is, if more air gets evacuated from any container of any size or thickness.

That's just nonsense. If you take a steel sphere 1' diameter, with a hollow space say 1/4" diameter in the centre, and evacuate it completely, you seriously think that will collapse due to 15 psi atmospheric pressure? You seriously have no business telling anyone to use their head and think if you say that it will.

On the other hand, if you increase the pressure inside such a vessel, I similarly can imagine it would easily contain 10 atmospheres (150 psi), if not 100. I'd bet more than 100.

So even without doing any calculations and relying on "common sense" it's obvious you're wrong. The tricky part is figuring out how little material you need to build a strong enough vessel. I've worked with little compressor tanks that hold 100 psi no problem. I'd guess they were maybe 3-4 cubic feet in volume, made of probably no more than 1/8" thick steel. Although I doubt the same tank could hold a vacuum at 1 atmosphere. Remember though that a space craft only has to contain 15psi internal pressure, which is a much simpler design.
Title: Re: Space Flight
Post by: markjo on June 17, 2013, 12:30:03 PM
The atmosphere will crush ANYTHING no matter how strong it is, if more air gets evacuated from any container of any size or thickness.
This is the part where we just can't seem to agree.  The examples that you give of things that implode under a vacuum are things that aren't designed to handle a vacuum.  Sure, it may seem like common sense that nature abhors a vacuum and wants to fill that empty space, but engineers go out of their way to defy common sense and make pressure vessels that can resist the tremendous forces involved when working with vacuums.
Engineers don't design anything to withstand a zero psi vacuum,
They design chambers that can basically act like a vacuum, as in, they can keep designing to get closer to one... but they can never hit a complete vacuum.
But you've already agreed that space is not a perfect vacuum, so why are we still having this discussion?  You do realize that "vacuum" is not an absolute term, don't you?  When we say "the vacuum of space", we say it with the understanding that, even in deep space, there are still a number of atoms of various gasses (mostly hydrogen) per unit of volume present.  This is, by definition, not a perfect vacuum, but it is pretty darned close.

I suppose the burning questions that every one wants the answer to are; how close to a perfect vacuum do you believe space is and how close to a perfect vacuum do you believe can be resisted?
Title: Re: Space Flight
Post by: DuckDodgers on June 17, 2013, 12:32:28 PM
Scepti, let's ignore design and assume in each of these situations the containers remain intact.  Is there a difference between the overall situations in internal versus external pressures of containers with 15/30, 50/65, and 85/100 psi, read internal/external?  What I mean is,  is the strain on the containers essentially the same in each case?   What if it were external/internal?  In not concerned with how they got there,  just what is happening one they are there.
Title: Re: Space Flight
Post by: Shmeggley on June 17, 2013, 01:16:39 PM

Quote from: markjo link
I suppose the burning questions that every one wants the answer to are; how close to a perfect vacuum do you believe space is and how close to a perfect vacuum do you believe can be resisted?
Whatever psi of gas  inside a ship that has more psi than space, then it will equalise that pressure and the only way it can do this is to expand, which will breach the ship.

You're missing the point. We can build structures on Earth that could withstand thousands of psi, to the point where the outside pressure becomes irrelevant.

In a vacuum, or in an atmosphere, the inside pressure of a vessel will only breach the vessel if it's not strong enough. It's already been demonstrated that we can build vessels more than strong enough. I just spent nearly an entire working day in a vessel designed to run continously at 150 psi for months at a time. The measly 15 psi outside is not keeping it from bursting, the 1" thick steel shell is. You really have no idea what you're talking about, at all. I guess I should just be glad you're not an engineer? Or at least not one I have to work with.
Title: Re: Space Flight
Post by: markjo on June 17, 2013, 01:17:29 PM

Quote from: markjo link
I suppose the burning questions that every one wants the answer to are; how close to a perfect vacuum do you believe space is and how close to a perfect vacuum do you believe can be resisted?
Whatever psi of gas  inside a ship that has more psi than space, then it will equalise that pressure and the only way it can do this is to expand, which will breach the ship.
The thing is, though, that the psi outside the ship doesn't really know, or care, what the psi inside the ship is.  Remember that if there is zero pressure outside the ship, then that means that there is zero force acting on the outside of the ship.  The ship (pressure vessel) only needs to act against the pressure of the gas inside the ship (about 15 psi), which we have told you, over and over again, is a very reasonable engineering task.
Title: Re: Space Flight
Post by: Rama Set on June 17, 2013, 01:27:23 PM
In fact it is trivially easy.  Although the interior pressure will continue to press on the walls of the spacecraft, it will never apply more pressure than 14.7 psi, if fact it would probably be more pressure if someone leaned on the wall.  Use some common sense Sceptimatic.
Title: Re: Space Flight
Post by: Scintific Method on June 17, 2013, 03:38:11 PM
Quote from: Scintific Method
Adding heat energy to the can excites the air molecules inside, causing the pressure to rise in accordance with Gay-Lussac's law, eventually exceeding the pressure required to dislodge the lid of the can, allowing the heated gas to escape explosively. Nothing revolutionary about that, it was worked out 200 years ago. Try again.
The reason I used this example , if you can see past what I'm about to say, which I won;t hold my breath about...is:
The water molecules, in that dense air, turn to gas and expand inside the tin...but outside the tin, is a raging fire, which is consuming all of the oxygen and creating a partial vacuum around it, meaning there is very little air pushing against the outside of the can, which means that the longer the fire burns...the more that the can expands...blowing off the top, or the weakest point.

Picture the fire around the can...as the vacuum of space...
Note: I know space isn't fire....I'm saying, picture the fire around the can, as the consumption of air, as in a vacuum and you should see why a rocket would not work in a vacuum...but I know you won't.

Given that the same thing will happen if you use an electric stove (which does not consume or significantly heat the air around it) and dry air (air with no water vapour in it), all this proves is that you have an exceptionally poor understanding of the mechanics of air pressure.

Oh...and I didn't answer the other parts, because I couldn't without either admitting I was wrong, or making an even bigger fool of myself than I already have.

Seems about right.

I would have liked a response to this one though:

Think of high pressure, or dense pressure (SM: density and pressure are two different things, you seem to be confusing them) as a crowd of people in a tube train squashing each other and more people getting on at the next stop, creating an even denser crowd pushing against the train walls.
Well this is your compressed air...which isn't what we are dealing with here but it helps to differentiate.
Now think of low pressure as a lot less people on that train bumping into each other... [this part removed due to being incorrect]

...
...

Thinking like this, a vacuum is like a train with only one or two people in it, ambling about and only rarely bumping into the walls. This is actually a useful analogy, as even a pretty large crowd pressing on the outside of the train would not be able to collapse it, even if there were no-one inside. Of course, at some point there will be enough people outside to crush the train, and that would be equivalent to sending an evacuated vacuum chamber to the bottom of the ocean.

Edit: The train analogy can actually be used the other way around too. Think of a space craft in space as a train full of people parked at an empty platform. Try as they might, those people aren't getting out just by pushing on the walls of the train, even though there's no-one outside to stop them.

Add this to the person stepping off the boat pushing the boat backwards, even though the water provides more resistance to movement than air, and you have explanations for rockets and pressurized space vehicles.
Title: Re: Space Flight
Post by: 29silhouette on June 17, 2013, 08:53:50 PM
A space craft ONLY has to contain 15 psi internal pressure. This would be fine on earth.
In space, it would expand until it tears the craft apart.It basically gets agitated and starts running at the walls like a nutter.
So we have air inside a solid container (not rubber like a balloon) that somehow knows when there is 0 psi outside, and is therefore inclined to become agitated and start "running at the walls"? 

The air molecules just say, "Hey, I don't think there's any pressure on the other side of this solid metal wall, Let's go crazy!"

The atmosphere will crush ANYTHING no matter how strong it is, if more air gets evacuated from any container of any size or thickness.
Wrong.  The design of a container will determine if it's crushed.


The reason I used this example , if you can see past what I'm about to say, which I won;t hold my breath about...is:
The water molecules, in that dense air, turn to gas and expand inside the tin...but outside the tin, is a raging fire, which is consuming all of the oxygen and creating a partial vacuum around it, meaning there is very little air pushing against the outside of the can, which means that the longer the fire burns...the more that the can expands...blowing off the top, or the weakest point.
And what about the other gases (including oxygen) that will rush right in?  Are you saying nothing can handle a 14.7 psi difference (my air compressor holds 90 psi just fine in an environment of 14.7), but mere flames are solid enough to hold back 14.7 psi against a 'partial vaccum' (whatever psi you consider that) which just so happens to be a low enough pressure to cause a can to explode?
Title: Re: Space Flight
Post by: Puttah on June 17, 2013, 09:54:19 PM
So we have air inside a solid container (not rubber like a balloon) that somehow knows when there is 0 psi outside, and is therefore inclined to become agitated and start "running at the walls"? 

The air molecules just say, "Hey, I don't think there's any pressure on the other side of this solid metal wall, Let's go crazy!"

It's possible that the air molecules are a part of the NASA conspiracy.

Scepti, you've taken the stance that no material can contain any volume of air from a perfect vacuum outside (which is wrong but irrelevant) and you've already accepted that space isn't a perfect vacuum since we've had all those talks about satellites slowly losing altitude and no one has ever claimed that space is an absolutely perfect vacuum, so what is the problem here? There are SOME gases in space, albeit a tiny amount, so even though you're wrong about what you think a vacuum would do to a pressurized vessel, it doesn't even matter.
Title: Re: Space Flight
Post by: DuckDodgers on June 18, 2013, 04:50:51 AM
Scepti, let's ignore design and assume in each of these situations the containers remain intact.  Is there a difference between the overall situations in internal versus external pressures of containers with 15/30, 50/65, and 85/100 psi, read internal/external?  What I mean is,  is the strain on the containers essentially the same in each case?   What if it were external/internal?  In not concerned with how they got there,  just what is happening one they are there.
The containers are all getting (for want of a better word) battered.
It's just a case of how much force they take in that battering. (think of metal fatigue).
It's simply about force applied , inside and out and EVERYTHING on earth is governed by action and reaction in equal force.
Look at atmosphere, either inside or outside as 'people.'

You didn't really answer my question of what do you think would happen in those different situations.  Namely, do you think there is any difference in the strain that the containers experience in these situations?
Title: Re: Space Flight
Post by: spaceman spiff on June 18, 2013, 04:57:32 AM
I think there is a misunderstanding here about closed and open systems. If you have a sealed container at atmospheric pressure in a vacuum chamber, the air doesn't know what's the pressure outside, so it cannot try to equalize. The only thing it the air does is applying a pressure of 14.7 psi on the inner walls of the container. If said container was designed to withstand 14.7 psi from the inside out, it will stay there peacefully until something changes. The system is closed. As soon as you poke a hole in the container, the information about the outside pressure comes through and air will seep out because the container is not anymore a closed system.
The same works the other way around, like a container with vacuum inside under atmospheric pressure. Now the pressure is applied to the outer walls of the container.
In short, in a closed system, the pressure is not trying to equalize with anything but just applying a force to the walls.
Title: Re: Space Flight
Post by: Rama Set on June 18, 2013, 05:25:15 AM
So why don't evacuated lightbulbs or vacuum tubes implode?
Title: Re: Space Flight
Post by: Rama Set on June 18, 2013, 05:52:03 AM
So why don't evacuated lightbulbs or vacuum tubes implode?
Because they are only evacuated to a safe pressure...they are not a true vacuum.

There is no air inside a vacuum tube, in any significant quantity.  Air inside a vacuum tube is detrimental to its proper functioning.  They are less than a millionth of sea-level atmospheric pressure.
Title: Re: Space Flight
Post by: Scintific Method on June 18, 2013, 05:54:34 AM
So why don't evacuated lightbulbs or vacuum tubes implode?
Because they are only evacuated to a safe pressure...they are not a true vacuum.

They only work because they are a near-perfect vacuum, any more than a few molecules of air remaining would stop them from working, or severely limit their useful life.

I'll amend that slightly: light bulbs can function when filled with an inert gas, but a vacuum tube must be a near-perfect vacuum to function at all, let alone as well as they do.
Title: Re: Space Flight
Post by: DuckDodgers on June 18, 2013, 05:59:16 AM
Scepti, let's ignore design and assume in each of these situations the containers remain intact.  Is there a difference between the overall situations in internal versus external pressures of containers with 15/30, 50/65, and 85/100 psi, read internal/external?  What I mean is,  is the strain on the containers essentially the same in each case?   What if it were external/internal?  In not concerned with how they got there,  just what is happening one they are there.
The containers are all getting (for want of a better word) battered.
It's just a case of how much force they take in that battering. (think of metal fatigue).
It's simply about force applied , inside and out and EVERYTHING on earth is governed by action and reaction in equal force.
Look at atmosphere, either inside or outside as 'people.'

You didn't really answer my question of what do you think would happen in those different situations.  Namely, do you think there is any difference in the strain that the containers experience in these situations?
I'll try and put it as simple as I can.

If you start to create a vacuum, you are releasing air right?
That air is now outside the container but cannot equalize with the atmospheric pressure so it fights to get back in...call it reinforcements if you want.
The more air taken out..the more stress is on the container, because more psi has went into the atmosphere making the atmosphere squash it back into the container...or try to///and is only held back by the sheer strength of the container holding it back.
You still failed to answer the question.   I'll make it easy on you,  is there any difference between those three pressure situations on the strain felt by the container?   I'll even give you a hint,  the correct answer isn't yes.
Title: Re: Space Flight
Post by: neimoka on June 18, 2013, 06:21:13 AM
Scepti,

what would you consider to be "vacuum"? I'm asking because surely you do realize that vacuum pump systems and chambers that get you to <0.00000000001 or so parts of normal atmospheric pressure are commercially available. That's ridiculously close to perfect vacuum. So at what point does vacuum become vacuum so to speak and utterly annihilate the container regardless of material or how it's built?

Like already said here what could crush a weak container is the pressure differential, and pressure is a measure or force per surface area (like, psi - pounds per square inch) and vacuum by itself does nothing - why would there be more outward force in a container placed in vacuum, than in a container that otherwise holds 30psi in 15psi ambient pressure? Because 15psi pressure differential is 15psi differential no matter what the actual pressure values on either side of the chamber wall happen to be.
Title: Re: Space Flight
Post by: Rama Set on June 18, 2013, 07:20:30 AM
So why don't evacuated lightbulbs or vacuum tubes implode?
Because they are only evacuated to a safe pressure...they are not a true vacuum.

They only work because they are a near-perfect vacuum, any more than a few molecules of air remaining would stop them from working, or severely limit their useful life.

I'll amend that slightly: light bulbs can function when filled with an inert gas, but a vacuum tube must be a near-perfect vacuum to function at all, let alone as well as they do.
Near perfect is not perfect.
Evacuate more air and your light bulb needs hoovering up.

Vacuum tubes do not all have inert gas in them.  They work without inert gas.
Title: Re: Space Flight
Post by: DuckDodgers on June 18, 2013, 07:23:11 AM
Scepti, let's ignore design and assume in each of these situations the containers remain intact.  Is there a difference between the overall situations in internal versus external pressures of containers with 15/30, 50/65, and 85/100 psi, read internal/external?  What I mean is,  is the strain on the containers essentially the same in each case?   What if it were external/internal?  In not concerned with how they got there,  just what is happening one they are there.
The containers are all getting (for want of a better word) battered.
It's just a case of how much force they take in that battering. (think of metal fatigue).
It's simply about force applied , inside and out and EVERYTHING on earth is governed by action and reaction in equal force.
Look at atmosphere, either inside or outside as 'people.'

You didn't really answer my question of what do you think would happen in those different situations.  Namely, do you think there is any difference in the strain that the containers experience in these situations?
I'll try and put it as simple as I can.

If you start to create a vacuum, you are releasing air right?
That air is now outside the container but cannot equalize with the atmospheric pressure so it fights to get back in...call it reinforcements if you want.
The more air taken out..the more stress is on the container, because more psi has went into the atmosphere making the atmosphere squash it back into the container...or try to///and is only held back by the sheer strength of the container holding it back.
You still failed to answer the question.   I'll make it easy on you,  is there any difference between those three pressure situations on the strain felt by the container?   I'll even give you a hint,  the correct answer isn't yes.
I'll make this simple for you.
Air molecules are constantly in motion unless at absolute zero.

Now what do you think would happen to your bed if a little kid kept on jumping up and down on it?
Eventually, the bed would sag and then break...but it would withstand the pressure for a long time.
Throw more kids on it and it will break a lot quicker.

Now let a big fat man onto it and get him to jump up and down,slowly. How long would it last?
Think about it.
You yet again failed to answer the simple question of is there anydifference in the pressure situations I described above.  Net 15 lbs of force per square inch is the same no matter what the environment.   Each situation had this amount of force either being aapplied outward or inward depending on the situation.  Now can you agree that we have containers that can handle this amount of force if there is pressure on both sides?
Title: Re: Space Flight
Post by: SuperHater7810 on June 18, 2013, 07:34:57 AM
Near perfect is not perfect.
Evacuate more air and your light bulb needs hoovering up.

There is no such thing as a perfect vacuum. Not even in outer space.
And also as people here have already have tried to explain. Is there is plenty more situations right here on earth where we get pressures far greater than they have to deal with in the vacuum of space.
THink about it.  If you have 15 PSI inside your space craft and 0 outside, that means there is only a difference of 15 psi.
But if you take a large truck tire that holds up to 100 psi and you have an atmospheric pressure pressure of 14.7 that gives you a pressure difference of  85.3 psi.
So there is much greater load on the wall of the truck tire than on the hull of your space craft.
Title: Re: Space Flight
Post by: Rama Set on June 18, 2013, 07:40:08 AM
So why don't evacuated lightbulbs or vacuum tubes implode?
Because they are only evacuated to a safe pressure...they are not a true vacuum.

They only work because they are a near-perfect vacuum, any more than a few molecules of air remaining would stop them from working, or severely limit their useful life.

I'll amend that slightly: light bulbs can function when filled with an inert gas, but a vacuum tube must be a near-perfect vacuum to function at all, let alone as well as they do.
Near perfect is not perfect.
Evacuate more air and your light bulb needs hoovering up.

You are obviously not making a distinction between a vacuum state, an absence of material, and vacuuming, the act of creating a pressure differeintial to move matter.  A vacuum state does not have different properties than something that has a millionth of an atmosphere of pressure.

Title: Re: Space Flight
Post by: DuckDodgers on June 18, 2013, 07:41:25 AM
Quote from: DuckDodgers
You yet again failed to answer the simple question of is there anydifference in the pressure situations I described above.  Net 15 lbs of force per square inch is the same no matter what the environment.   Each situation had this amount of force either being aapplied outward or inward depending on the situation.  Now can you agree that we have containers that can handle this amount of force if there is pressure on both sides?

You need to get your scientific head off and use some basic logic, because basic logic is a powerful tool, seriously.

the only time an equal force is applied to a container, is when that container is at atmospheric pressure, both inside and out, as in 'open.'

Once you evacuate a small amount of air, you have stolen some of that psi from inside of that container, as long as it seals as you take it out.

Now here's the key.
That air that you took from that container, is now a part of the atmospheric pressure but it's now added to that pressure, which means...the outside pressure is now a bit greater than the inside pressure of the container.
Keep taking the air out of that container and that air becomes part of the outside air pressure...creating more pressure as it squashes into it.
Can you understand now?
Do you even realize how insignificant the pressure increase would be from evacuating a small container?  It would not even register.   Now how about you put on your supposed common sense cap and think about this pressure deal.   We can build stuff to contain far more than 15 psi pressure differentials,  yet a 15 psi differential well destroy anything?  Is that common logic?
Title: Re: Space Flight
Post by: SuperHater7810 on June 18, 2013, 07:53:11 AM
Ok...deep breaths scepti.   :)

Let's take your large truck and 100 psi.
What you have done, is took 85.3 psi from the atmosphere and pumped it into the trucks tyre.
The atmosphere has to fill that gap from the top,Which immediately evens up the pressure against the tyre and stops it getting blown out.
Only the tyre wall itself if handling the stresses which it's designed to do.

If you over inflate it, you are then pulling more air from the atmosphere to do that, which means the atmosphere will drop down to equalize it, until that tyre bursts with one last pump or someone adding weight to it, like a bloke getting into the cab or a load being put on the trucks back, which compressed the tyre  and bang.

Ok so before I started inflating the tire the pressure of the earth atmosphere atmosphere was at 100 PSI.....? OK. ???
BUt even by your EXTREMELY flawed logic. Honestly I dont even know where to begin. If we are decreasing the atmospheric pressure as we are increasing the pressure inside the tire surely that should put even more strain on the wall of the tire.
Title: Re: Space Flight
Post by: SuperHater7810 on June 18, 2013, 07:59:52 AM
SO how do i get 85.3 PSI out of the atmosphere if there is only 14.7 psi to begin with. Who doesn't understand how air pressure works now?
Title: Re: Space Flight
Post by: Rama Set on June 18, 2013, 08:18:26 AM
So why don't evacuated lightbulbs or vacuum tubes implode?
Because they are only evacuated to a safe pressure...they are not a true vacuum.

They only work because they are a near-perfect vacuum, any more than a few molecules of air remaining would stop them from working, or severely limit their useful life.

I'll amend that slightly: light bulbs can function when filled with an inert gas, but a vacuum tube must be a near-perfect vacuum to function at all, let alone as well as they do.
Near perfect is not perfect.
Evacuate more air and your light bulb needs hoovering up.

You are obviously not making a distinction between a vacuum state, an absence of material, and vacuuming, the act of creating a pressure differiential to move matter.  A vacuum state does not have different properties than something that has a millionth of an atmosphere of pressure.
Would you care to elaborate on this in simple terms, as your scientific indoctrinated head is rearing.

What don't you understand?  Be specific please as you tend to need hand-holding and I would rather do as little as possible.
Title: Re: Space Flight
Post by: Puttah on June 18, 2013, 08:19:10 AM
Ok...deep breaths scepti.   :)

Let's take your large truck and 100 psi.
What you have done, is took 85.3 psi from the atmosphere and pumped it into the trucks tyre.
The atmosphere has to fill that gap from the top,Which immediately evens up the pressure against the tyre and stops it getting blown out.
Only the tyre wall itself if handling the stresses which it's designed to do.

If you over inflate it, you are then pulling more air from the atmosphere to do that, which means the atmosphere will drop down to equalize it, until that tyre bursts with one last pump or someone adding weight to it, like a bloke getting into the cab or a load being put on the trucks back, which compressed the tyre  and bang.

Honestly, does this make sense to anyone here? Scepti, your logic is with you and you only.

What you have done, is took 85.3 psi from the atmosphere and pumped it into the trucks tyre.

LOL look at this nonsense!
Title: Re: Space Flight
Post by: DuckDodgers on June 18, 2013, 08:25:11 AM
Ok...deep breaths scepti.   :)

Let's take your large truck and 100 psi.
What you have done, is took 85.3 psi from the atmosphere and pumped it into the trucks tyre.
The atmosphere has to fill that gap from the top,Which immediately evens up the pressure against the tyre and stops it getting blown out.
Only the tyre wall itself if handling the stresses which it's designed to do.

If you over inflate it, you are then pulling more air from the atmosphere to do that, which means the atmosphere will drop down to equalize it, until that tyre bursts with one last pump or someone adding weight to it, like a bloke getting into the cab or a load being put on the trucks back, which compressed the tyre  and bang.

Honestly, does this make sense to anyone here? Scepti, your logic is with you and you only.

What you have done, is took 85.3 psi from the atmosphere and pumped it into the trucks tyre.

LOL look at this nonsense!
What part of this easy explanation don't you get?

I'm repeating myself here,  but pressure isn't a cause,  it's an effect.   It is directly proportional to mass and temperature and inversely proportional to volume.   It seems as if you believe it to be pressure that causes an amount of air to be somewhere when it is really the amount of air that causes the pressure.
Title: Re: Space Flight
Post by: Rama Set on June 18, 2013, 08:33:36 AM
So why don't evacuated lightbulbs or vacuum tubes implode?
Because they are only evacuated to a safe pressure...they are not a true vacuum.

They only work because they are a near-perfect vacuum, any more than a few molecules of air remaining would stop them from working, or severely limit their useful life.

I'll amend that slightly: light bulbs can function when filled with an inert gas, but a vacuum tube must be a near-perfect vacuum to function at all, let alone as well as they do.
Near perfect is not perfect.
Evacuate more air and your light bulb needs hoovering up.

You are obviously not making a distinction between a vacuum state, an absence of material, and vacuuming, the act of creating a pressure differiential to move matter.  A vacuum state does not have different properties than something that has a millionth of an atmosphere of pressure.
Would you care to elaborate on this in simple terms, as your scientific indoctrinated head is rearing.

What don't you understand?  Be specific please as you tend to need hand-holding and I would rather do as little as possible.
Then do as little as possible.
Don't type.

I dont mean any offense, but whenever you do not understand something someone else says, you ask them to dumb it down and explain every little detail to you.  I personally think that people should try and understand things themselves, so that they can get the firmest grasp possible.
Title: Re: Space Flight
Post by: DuckDodgers on June 18, 2013, 08:45:06 AM
Ok...deep breaths scepti.   :)

Let's take your large truck and 100 psi.
What you have done, is took 85.3 psi from the atmosphere and pumped it into the trucks tyre.
The atmosphere has to fill that gap from the top,Which immediately evens up the pressure against the tyre and stops it getting blown out.
Only the tyre wall itself if handling the stresses which it's designed to do.

If you over inflate it, you are then pulling more air from the atmosphere to do that, which means the atmosphere will drop down to equalize it, until that tyre bursts with one last pump or someone adding weight to it, like a bloke getting into the cab or a load being put on the trucks back, which compressed the tyre  and bang.

Honestly, does this make sense to anyone here? Scepti, your logic is with you and you only.

What you have done, is took 85.3 psi from the atmosphere and pumped it into the trucks tyre.

LOL look at this nonsense!
What part of this easy explanation don't you get?

I'm repeating myself here,  but pressure isn't a cause,  it's an effect.   It is directly proportional to mass and temperature and inversely proportional to volume.   It seems as if you believe it to be pressure that causes an amount of air to be somewhere when it is really the amount of air that causes the pressure.
Oh come off it.  ;D
Air molecules stacked on top of each other, create pressure.
Air is dense to quite a big height and gets thinner all the way up, until there is none.
It's all stacked on top of each other which squashed the molecules into a dense state at sea level and it called air pressure.
Try and twist this again and you're blanked.
I'm doing no twisting,  just trying to comprehend yourunderstanding of pressure and it seems like you have several misconceptions.You are obviously not able to be corrected, so I'll do you the favor by just abandoning trying to.   I'd suggest you take a look at a basic physics textbook on the chapter of pressure to get a firm grasp of it.  Once the pressure deal is resolved (if ever) maybe we could finally get back to how rockets can and do function in vacuums.  Good day to you,  and to my fellow RE'ers, keep fighting the good fight. 
Title: Re: Space Flight
Post by: Rama Set on June 18, 2013, 08:52:13 AM

Quote from: Rama Set
I dont mean any offense, but whenever you do not understand something someone else says, you ask them to dumb it down and explain every little detail to you.  I personally think that people should try and understand things themselves, so that they can get the firmest grasp possible.
No offence taken.
Also, I know what I'm talking about with this and I also like to play it simple, without inversely proportionate to its mass times weight divided by quantum bean bags relative to a vacuum placed under a quasar particle echo cluster that changes its whole momentum when squared against time under cosmic conditions.  ;D

I think you get my meaning, because that's what people try to pull and when they do, they get laughed at.
So play it simple for all people to see and grasp, or don't bother.
It's really as simple as that.  :)
Oh and no offence.

I am sorry you do not understand what I said.  There are easy ways to remedy that. But believe everyone on this site, that you have major issues in understanding how vacuums and pressure work.  Your logic is flawed.  If you read through posts by RE postersin this thread to other FE believers, they do not always disagree with matters of scientific knowledge.  You really need to get outside your own head and figure this out. 

In regards to my previous post.  I was saying there is a difference between a vacuum, the noun referring to space that contains no matter, and the verb to vacuum, to create a difference in pressure that creates suction.

With a vacuum state, the change in pressure upon a container is instantaneous, but if it can withstand that first change in pressure (which is violent) then the pressure will become constant, like the air on your skin.
Title: Re: Space Flight
Post by: Puttah on June 18, 2013, 09:18:08 AM
Yes the pressure would become constant..but only when the container is either crushed and breached on earth unless the container is evacuated within safe limits but it will be expanded and breached in space.

There is no other outcome.

But space isn't a perfect vacuum and since your flawed and baseless argument relies on that, then you have no reason to claim that spaceships will explode.
Title: Re: Space Flight
Post by: markjo on June 18, 2013, 09:19:18 AM
You can't have open systems when under pressure of air compression or vacuum.
Sure you can.  Don't you ever watch the weather channel?  They talk about high and low pressure systems all the time.  Granted, the pressure differentials in weather systems aren't anywhere near the ones that we're discussing, but the basic concepts are the same.  Essentially you have differences in air pressure that don't equalize themselves instantaneously.
Title: Re: Space Flight
Post by: markjo on June 18, 2013, 09:36:02 AM
Space doesn't have to be a perfect vacuum.
Let's allow it 1 psi then.
Ok, so if your space rocket is carrying more than 1 psi of fuel or air, then it will give up all, but 1 psi of it to space.

You still lose your rocket, so what are you going to say now?

By that same logic, if your car tire has more than 14.7 psi of air, then it will give up all but 14.7 psi to the atmosphere and we would all be driving on flat tires.  That just doesn't make any sense.
Title: Re: Space Flight
Post by: markjo on June 18, 2013, 09:44:51 AM
Space doesn't have to be a perfect vacuum.
Let's allow it 1 psi then.
Ok, so if your space rocket is carrying more than 1 psi of fuel or air, then it will give up all, but 1 psi of it to space.

You still lose your rocket, so what are you going to say now?

By that same logic, if your car tire has more than 14.7 psi of air, then it will give up all but 14.7 psi to the atmosphere and we would all be driving on flat tires.  That just doesn't make any sense.
Your car tyre is designed to hold 30+ psi against the atmosphere.
And space ships are designed to hold 15 psi against a vacuum.   So, tell me again, how is a tire holding back 30 psi against a 14.7 psi atmosphere any different from a space ship holding back 15 psi against a 0 (or 1) psi vacuum?  Better yet, why doesn't the near perfect vacuum of space suck away our 14.7 psi atmosphere in order to equalize the pressure?
Title: Re: Space Flight
Post by: Rama Set on June 18, 2013, 10:42:52 AM
Quote from: Rama Set
In regards to my previous post.  I was saying there is a difference between a vacuum, the noun referring to space that contains no matter, and the verb to vacuum, to create a difference in pressure that creates suction.

I'm well aware there is a difference and I've been saying it all along.
It still doesn't change the fact that the more air you evacuate from a container...eventually it will implode on earth, because a true vacuum cannot be created, so anything that tries to stand up to it, will be crushed eventually, on earth.

Just because we cannot create a true vacuum, does not mean it will crush anything.  You appear to think a vacuum state is all powerful.  Really a very strong vacuum cleaner is much more powerful.  0psi > -5psi.  I do not understand why you think the pressure differential created by a vacuum is infinitely powerful.  Why can't a vacuum tube, already at 0.000000147 psi go a few millionths psi further? 

A submarine can withstand the ocean constantly applying 190 psi with little trouble, but if you take all the air out, all of the sudden, it cannot take 14.7 psi.

I agree that if you continuously vacuum out the submarine (apply a negative pressure to it) then eventually it will implode, but that is not what a vacuum state does.  A vacuum state will try and get the submarine to 0 psi, not negative psi.  Once the pressure inside gets to 0 psi, there is only the stress of the atmosphere on the submarine, which is a paltry 14.7 psi, easily withstood. 

The same thing happens in space.  The near-vacuum of space will suck everything out of a container that is exposed to the vacuum until it gets to 0 psi (actually not 0 psi, but 0.00000000001 psi) and then there will be no more suction.  And since there is no outside pressure from an atmosphere in space, it is actually less stressful for the container.



Quote
Quote from: Rama Set
With a vacuum state, the change in pressure upon a container is instantaneous, but if it can withstand that first change in pressure (which is violent) then the pressure will become constant, like the air on your skin.

Yes the pressure would become constant..but only when the container is either crushed and breached (earth) if the container is evacuated within safe limits but it will be expanded and breached space.

There is no other outcome.

See my above comment. This is only true if you continue to vacuum out the container after its pressure has reached 0psi.  This would not happen in space.
Title: Re: Space Flight
Post by: neimoka on June 18, 2013, 11:09:49 AM
Scepti,

what would you consider to be "vacuum"? I'm asking because surely you do realize that vacuum pump systems and chambers that get you to <0.00000000001 or so parts of normal atmospheric pressure are commercially available. That's ridiculously close to perfect vacuum. So at what point does vacuum become vacuum so to speak and utterly annihilate the container regardless of material or how it's built?

Like already said here what could crush a weak container is the pressure differential, and pressure is a measure or force per surface area (like, psi - pounds per square inch) and vacuum by itself does nothing - why would there be more outward force in a container placed in vacuum, than in a container that otherwise holds 30psi in 15psi ambient pressure? Because 15psi pressure differential is 15psi differential no matter what the actual pressure values on either side of the chamber wall happen to be.
Atmospheric pressure at sea level is 14.7 psi.
That's fine as it is but if you change that by evacuating a container of air , which was obviously at the same pressure, that air becomes a part of the atmospheric pressure pushing back against the container.
The more air you take out, the more it adds to the atmospheric pressure outside, creating more force.
Can you see what I mean here?

I see what you mean but the volume of atmosphere is so large in comparison to any man made container that there will be no measurable change of atmospheric pressure so how is that relevant - if that was an answer to my question I don't get it. Were you saying that a near perfect vacuum would not crush anything but a perfect vacuum would? If so then why couldn't anything survive in earth orbit, vacuum certainly isn't perfect there? And why would an unbelievably minute change of less than 10^-7Pa in pressure make such a difference, going from near perfect to perfect vacuum (assuming we could find a perfect vacuum somewhere)?

So facts are that we can produce ourselves or find in space a near complete vacuum, and when we do, presuming an appropriately manufactured pressure container... what happens? Observation says, not much.

By the way, atmospheric pressure at around 100km, altitude at which our atmosphere is usually considered to end, atmospheric pressure is less than 0.00001 psi - much less than 1psi.
Title: Re: Space Flight
Post by: markjo on June 18, 2013, 11:33:20 AM
Each time I pump air into the tyre, I'm compressing those balls, more and more into it and the atmosphere drops down to fill the void I pumped out of.
So you end up with 30 psi of compressed air/balls into the tyre, whilst the same weight has compressed around that tyre, trying to equalise the pressure all the time.
You see, the tyre being pumped up, is also pushing the air away from it, making itself bigger against it which is immediately equalised by air trying to fill that expansion created outside.
Wait a minute.  Are you saying that as you pump 30 psi of air into the tire, the atmosphere outside the tire equalizes to 30 psi as well?  ???
Title: Re: Space Flight
Post by: markjo on June 18, 2013, 12:12:47 PM
In the mean time...your tyre is inflating and pushing against the atmosphere, because it's gaining volume due to the air molecules trying to expand back to normal but the tyre and outside pressure are holding them back...
I will agree with you that the higher air pressure within the tire is working against the walls of the tire trying to expand it, but the atmosphere can't really help the tire with its internal struggle.  For one thing, how can a measly 14.7 psi of atmosphere help hold back 30 psi of air within the tire?  It's like trying to use a marshmallow to hold back an angry grizzly bear.

Quote
...until you over pump it, where the tyre gives way and explodes the compressed air molecules back into shape, smashing back against the atmosphere and creating an air crash, which you hear as a bang.
Well, that actually depends on the nature of the tire failure.  Sometimes you get a hiss of air escaping slowly instead of a loud bang.
Title: Re: Space Flight
Post by: neimoka on June 18, 2013, 01:06:49 PM
Quote from: neimoka
I see what you mean but the volume of atmosphere is so large in comparison to any man made container that there will be no measurable change of atmospheric pressure so how is that relevant - if that was an answer to my question I don't get it.

Suck on a glass bottle till your tongue gets jammed in.
It hurts right and also you think that your tongue has been sucked into the bottle but it hasn't.
What you have done, is sucked some air out of the bottle and made a small vacuum, as strong as your mouth suction will allow.
Because you did this...you evacuated that small amount of air, back into the atmosphere, which now forces it's way back to the place where it was evacuated from and looks for the weakest part to equalise it, which is through the sides of your tongue.
So, as you sit there thinking your tongue is being sucked in, it's actually being pushed in, because the air pressure you created outside, now exerts it's pressure on the sides of your tongue, at the weakest point and drives it in the bottle until the thickness of your tongue creates the ultimate seal.

If you could keep sucking, it would literally dislodge your tongue, but you would be screaming by that time and use your own force to pull it out lol.
That is the power of atmospheric pressure when it's messed with.
Seriously, it's underestimated greatly.

OK. How does that make any difference?

You (or, I) are in fact able to create a quite good vacuum just by using your mouth, adding that last fraction would not make much difference so you'd scream in agony as your tongue rips off.

Also, such a pushing action as you describe is not necessary; look up pressure gradient.

And as an amusing relief, a video on the subject of sucking: World's Longest Vertical Straw (http://#ws)

Quote from: neimoka
Were you saying that a near perfect vacuum would not crush anything but a perfect vacuum would? If so then why couldn't anything survive in earth orbit, vacuum certainly isn't perfect there? And why would an unbelievably minute change of less than 10^-7Pa in pressure make such a difference, going from near perfect to perfect vacuum (assuming we could find a perfect vacuum somewhere)?
A vacuum doesn't crush...the air pressure does.
agreed.

Quote from: neimoka
So facts are that we can produce ourselves or find in space a near complete vacuum, and when we do, presuming an appropriately manufactured pressure container... what happens? Observation says, not much.

You haven't observed it, nor ever will, because we cannot get up there to find out.

Quote from: neimoka
By the way, atmospheric pressure at around 100km, altitude at which our atmosphere is usually considered to end, atmospheric pressure is less than 0.00001 psi - much less than 1psi.
It will still be smaller than what is inside a rocket, so the same applies...a breached rocket.

What's with the personal attack? Matter of fact is that I have observed it. I have personally created a nearly complete vacuum, measured it, observed it. Why would you have any reason to doubt that is beyond me.

Also, I still can not see you having offered any explanation for why a minute difference in pressures would utterly crush anything as long as the other side is vacuum - which you haven't defined yet as I originally requested? You said that anything that goes to space will be crushed, but vacuum in earth orbit altitudes is not any more perfect than the man-made vacuums that we can make here on earth so why is it so much more destructive?
Title: Re: Space Flight
Post by: markjo on June 18, 2013, 01:19:56 PM
Because you have compressed 15.3 psi into the tyre from the atmosphere, so the atmosphere  equalises that pressure around the volume of the tyre, only.
You have increased the external volume of that tyre, allowing more  air molecules on to the outside of the tyre which gives them more equal push back due to the atmosphere filling a larger area that to you looks nothing but to molecules, it's huge.
Think of your party balloon and how you compress air into that and its volume greatly increases right.
Inside of it, is compressed air molecules but outside the atmosphere creates pressure against that by allowing more molecules to push down onto a larger surface area.

Except that the increase in volume of the tire is fairly insignificant.  A tire is much stronger and more rigid than a party balloon, so it really isn't a fair comparison between the two.
Title: Re: Space Flight
Post by: sokarul on June 18, 2013, 03:14:01 PM
Suck on a glass bottle till your tongue gets jammed in.
It hurts right and also you think that your tongue has been sucked into the bottle but it hasn't.
What you have done, is sucked some air out of the bottle and made a small vacuum, as strong as your mouth suction will allow.
Because you did this...you evacuated that small amount of air, back into the atmosphere, which now forces it's way back to the place where it was evacuated from and looks for the weakest part to equalise it, which is through the sides of your tongue.
So, as you sit there thinking your tongue is being sucked in, it's actually being pushed in
, because the air pressure you created outside, now exerts it's pressure on the sides of your tongue, at the weakest point and drives it in the bottle until the thickness of your tongue creates the ultimate seal.
Ok to end this discussion. You agree that a rocket in space would try to equal to the pressure of space. You agree the vacuum of space means nothing and the pressure inside the rocket wants to get out. So you agree that if a rocket was strong enough to not allow the pressure inside to equalize then it wouldn't. Glad you agree that rockets can sit in space. END
 
Title: Re: Space Flight
Post by: 29silhouette on June 18, 2013, 06:30:47 PM
Ok...deep breaths scepti.   :)

Let's take your large truck and 100 psi.
What you have done, is took 85.3 psi from the atmosphere and pumped it into the trucks tyre.
The atmosphere has to fill that gap from the top,Which immediately evens up the pressure against the tyre and stops it getting blown out.

If you over inflate it, you are then pulling more air from the atmosphere to do that, which means the atmosphere will drop down to equalize it

The trucks tyre is 100 psi. The atmosphere stays at 14.7 psi, always under normal conditions.

So is there an 85 psi difference between the inside and outside of the tire or not?

Space doesn't have to be a perfect vacuum.
Let's allow it 1 psi then.
Ok, so if your space rocket is carrying more than 1 psi of fuel or air, then it will give up all, but 1 psi of it to space.

You still lose your rocket, so what are you going to say now?

Are you now saying a difference of more than 1 psi will cause a container to fail? 
Title: Re: Space Flight
Post by: Antonio on June 18, 2013, 08:59:43 PM
To clarify things, let's take a little example.
Let's design an emtpy little metal ball , giving it 10 square inches total surface.
As the air inside is at the same presssure that the outside, his surface do not withstand any force.

Now, let's add 1 psi into this ball
We should agree that
- The absolute pressure inside the cube is 15.7 psi
- the "forces" against the metal surface equals (15.7-14.7)x10=10 pounds  (nevermind the simplification of force and weight)

Then tell me now how much would be the forces acting on it

if I go up to the Mt Everest, (we assume that the atmospheric pressure, there, is about 5 psi),
if I go at 40 000 ft , with an atmospheric pressure of about 2.5 psi
and finally if I put it in near space, with a residual pressure of 0,0001 psi.

Don't go with Hulk, crowds, molecules rushing out, and so on, just go with plain basics.
And don't invoke weird science or twisted things, this is how barometers work, as you may know.
Title: Re: Space Flight
Post by: spaceman spiff on June 19, 2013, 06:19:33 AM
Quote
To your eyes it's fairly insignificant...but to air molecules squashing against it, equalising the pressure...it's massively significant.
Equalizing the pressure with what?
Quote
Can one more small breath cause a fully inflated  balloon to go bang?
It depends. If before this small breath the baloon was not on the limit of its resistance, no.
Quote
No.
There is no difference, because the psi inside has been equalised by the outside pressure. Action and equal and opposite reaction. It's the law of the earth, no matter what.
But the tire is at 100 psi and the atmosphere at 14.7. They are not equal, nor they can be equal since they are not in contact with each other.
Quote
14.7 psi in more of more excited external air against the 15.7 psi of less excited air.
What does this mean? And how can you know which one is more excited, since "excited" usually refers to temperature. What if they are both at the same temperature?
Quote
Quote
if I go up to the Mt Everest, (we assume that the atmospheric pressure, there, is about 5 psi),
if I go at 40 000 ft , with an atmospheric pressure of about 2.5 psi
and finally if I put it in near space, with a residual pressure of 0,0001 psi.
The ball becomes an open ball, simple as that.
This is where you are wrong. The air inside the ball doesn't know about the outside environment, so it cannot try to equalize anything. The only thing that changes is that the force acting on the inner walls of the ball is greater and greater than the force on the outer walls. What you are basically saying is that we can't build anything to resist a pressure difference of 15 psi.
Title: Re: Space Flight
Post by: neimoka on June 19, 2013, 07:27:45 AM

Quote from: neimoka
Were you saying that a near perfect vacuum would not crush anything but a perfect vacuum would? If so then why couldn't anything survive in earth orbit, vacuum certainly isn't perfect there? And why would an unbelievably minute change of less than 10^-7Pa in pressure make such a difference, going from near perfect to perfect vacuum (assuming we could find a perfect vacuum somewhere)?
I can't help that you don't understand. It's not because you can't...it's because your head is saturated with the indoctrinated bull shit you've had drummed into it , all your life.

Quote from: neimoka
What's with the personal attack?

What personal attack?
The one where you called me a liar.
Quote from: neimoka
Matter of fact is that I have observed it. I have personally created a nearly complete vacuum, measured it, observed it. Why would you have any reason to doubt that is beyond me.
Many people have created close to a vacuum.
None have created a complete vacuum.
Noone has claimed to have produced a perfect vacuum, what are you talking about this time?!? I'll try to be more direct with my question - we can produce near-perfect vacuums right here on earth, many people do it on a regular basis such as myself, and our pressure vessels handle it just fine. Now on earth's orbit the vacuum isn't perfect either so why the near vacuum of space destroys anything but manmade near vacuum does not?

Also you have not defined what you mean by vacuum when you say that nothing can survive in vacuum? It's obviously OK to have a vessel containing 30psi in 15 psi atmosphere, 20psi in 5psi atmosphere is still ok, 13psi in 2psi is still ok, so at what point even the strongest steel container absolutely must break?

Quote from: neimoka
Also, I still can not see you having offered any explanation for why a minute difference in pressures would utterly crush anything as long as the other side is vacuum - which you haven't defined yet as I originally requested? You said that anything that goes to space will be crushed, but vacuum in earth orbit altitudes is not any more perfect than the man-made vacuums that we can make here on earth so why is it so much more destructive?
That's because you appear not to be able to logically think.

Have you ever inflated a balloon and slowly but surely just added a tiny little bit more pressure and then a teeny bit more and the just an incey wincey bit more pressure, until, what?
As a matter of fact I have. And as a matter of fact I have also produced a near vacuum in a rigid steel container, have you? You pump air out of it, then a little more, until, what?

And I'll ask once more, perhaps you'd care to answer, a) why is the minute change of 1x10^-10Pa from near vacuum to perfect vacuum so important to you? You seem to believe that a perfect vacuum would be something almost magical that would destroy absolutely anything. We have nothing in our base of knowledge to support that. And b), since the vacuum in earth orbit altitudes is far from absolutely perfect, why would you insist that anything that gets there must be immediately destroyed when we can see for ourselves, without going to space, that containers capable of not being destroyed are not that difficult to make. Thanks for your time.
Title: Re: Space Flight
Post by: neimoka on June 19, 2013, 07:37:35 AM
Have you read any of this topic?

I'm afraid the more relevant question is if you've understood or even tried to understand anything of what's been explained to you in this thread :(
Title: Re: Space Flight
Post by: Antonio on June 19, 2013, 07:41:55 AM
Quote from: Antonio
To clarify things, let's take a little example.
Let's design an emtpy little metal ball , giving it 10 square inches total surface.
As the air inside is at the same presssure that the outside, his surface do not withstand any force.

Now, let's add 1 psi into this ball
We should agree that
- The absolute pressure inside the cube is 15.7 psi
- the "forces" against the metal surface equals (15.7-14.7)x10=10 pounds  (nevermind the simplification of force and weight)

Then tell me now how much would be the forces acting on it
14.7 psi in more of more excited external air against the 15.7 psi of less excited air.

Quote from: Antonio
if I go up to the Mt Everest, (we assume that the atmospheric pressure, there, is about 5 psi),
if I go at 40 000 ft , with an atmospheric pressure of about 2.5 psi
and finally if I put it in near space, with a residual pressure of 0,0001 psi.
The ball becomes an open ball, simple as that.

Quote from: Antonio
Don't go with Hulk, crowds, molecules rushing out, and so on, just go with plain basics.
And don't invoke weird science or twisted things, this is how barometers work, as you may know.
I'm not sure what you are getting at with this bit.
We've discussed barometers...don;t you read the threads?

You are avoiding the question. I do not care about notions of more or less "excited" air.
You have extensively claimed that everything explodes in vacuum, but I'm asking you to give some numbers like I did, not claims.
So I please go further and give the values of the forces for an external pressure of 5, 2.5 and 0.0001 psi.
Again, no trick, very basic and simple question.
I'm just asking you to give some substance to your claims

 
Title: Re: Space Flight
Post by: neimoka on June 19, 2013, 08:13:35 AM

Quote from: neimoka
The one where you called me a liar.

Show me where I called you a liar.

Here:
Quote from: neimoka
So facts are that we can produce ourselves or find in space a near complete vacuum, and when we do, presuming an appropriately manufactured pressure container... what happens? Observation says, not much.
You haven't observed it, nor ever will
Quote from: neimoka
Noone has claimed to have produced a perfect vacuum, what are you talking about this time?!? I'll try to be more direct with my question - we can produce near-perfect vacuums right here on earth, many people do it on a regular basis such as myself, and our pressure vessels handle it just fine. Now on earth's orbit the vacuum isn't perfect either so why the near vacuum of space destroys anything but manmade near vacuum does not?

Read back in the topic. I'm not explaining it all again.
There's no need to explain again since you haven't explained the first time, you've only given vague analogues to direct questions instead of at least trying to answer them. It is still unclear what you consider to be a vacuum for starters, and why a 0.0001/0Pa pressure difference destroys anything when far greater differences aren't a problem.




Have you ever inflated a balloon and slowly but surely just added a tiny little bit more pressure and then a teeny bit more and the just an incey wincey bit more pressure, until, what?

Quote from: neimoka
As a matter of fact I have. And as a matter of fact I have also produced a near vacuum in a rigid steel container, have you? You pump air out of it, then a little more, until, what?

If you keep doing it and the pump is strong, you will implode it. Guaranteed.
And here we are at the heart of this all. How do you know that? On what experiments, on what data, is your reasoning based? Do you know of a single instance where someone, anyone, was not able to produce a durable enough vacuum chamber, anything just imploded? I for one have utterly failed to implode a chamber with 1/4" thick steel walls, no matter how hard I've tried. So at what point and why does the vacuum become an absolutely irresistible force?

Quote from: neimoka
And I'll ask once more, perhaps you'd care to answer, a) why is the minute change of 1x10^-10Pa from near vacuum to perfect vacuum so important to you? You seem to believe that a perfect vacuum would be something almost magical that would destroy absolutely anything. We have nothing in our base of knowledge to support that. And b), since the vacuum in earth orbit altitudes is far from absolutely perfect, why would you insist that anything that gets there must be immediately destroyed when we can see for ourselves, without going to space, that containers capable of not being destroyed are not that difficult to make. Thanks for your time.
Type normal. I'm not interested in your 10 to the power crap.
Oh sorry, I didn't realize you don't understand notation. Do you prefer fractions? What units of measure do you use? That's 1/10000000000000 of normal atmospheric pressure, is that better?
Title: Re: Space Flight
Post by: neimoka on June 19, 2013, 08:55:35 AM
I merely asked, rather politely I might add, how do you define a vacuum and why less than a millibar of pressure does what hundreds can not, these are not simple enough?

I see by now that this is just another thing you decided by yourself on some gut feeling instead of looking out to actually learn something, so I guess the discussion really is done.
Title: Re: Space Flight
Post by: Puttah on June 19, 2013, 09:39:07 AM
Quote from: neimoka
And I'll ask once more, perhaps you'd care to answer, a) why is the minute change of 1x10^-10Pa from near vacuum to perfect vacuum so important to you? You seem to believe that a perfect vacuum would be something almost magical that would destroy absolutely anything. We have nothing in our base of knowledge to support that. And b), since the vacuum in earth orbit altitudes is far from absolutely perfect, why would you insist that anything that gets there must be immediately destroyed when we can see for ourselves, without going to space, that containers capable of not being destroyed are not that difficult to make. Thanks for your time.
Type normal. I'm not interested in your 10 to the power crap.
Oh sorry, I didn't realize you don't understand notation. Do you prefer fractions? What units of measure do you use? That's 1/10000000000000 of normal atmospheric pressure, is that better?

Scepti's genius doesn't come from understanding basic maths, it comes from his logic. And yes, that's the same "logic" that you're witnessing here in this thread.

Arbitrarily qualitative terms such as "very close" are much rather preferred. For example, at which point will a 1'' thick steel ball with inner radius 1'' and outer radius 2'' collapse due to the vacuum created inside of it? When it's VERY close to a perfect vacuum.
Title: Re: Space Flight
Post by: Scintific Method on June 19, 2013, 02:56:11 PM
When you start using your logic and playing it simple, I'm always game.
Start your little antics and you will get a weak response.

I tried that with the train example, but never got a response.

To recap:
empty train = vacuum,
medium crowd outside pressing on walls = atmosphere,
Train does not collapse.

Half-full train = space craft,
Empty platform = vacuum of space,
Train does not burst.

Logical and simple, what more could you want?
Title: Re: Space Flight
Post by: Scintific Method on June 19, 2013, 08:48:00 PM
Logical and simple, what more could you want?

Something that does not disagree with his preconceived notions. This thread is like a goldmine for ignorance, I now understand why even the other FE'ers don't associate with Sceptimatic.

Yeah, even after 43 pages of being shown exactly why he's wrong, and providing his own examples which (accidentally) show him to be wrong, scepti still believes he's "100% right".
Title: Re: Space Flight
Post by: 29silhouette on June 19, 2013, 08:57:52 PM
Quote from: 29silhouette
So is there an 85 psi difference between the inside and outside of the tire or not?

No.
There is no difference, because the psi inside has been equalised by the outside pressure. Action and equal and opposite reaction. It's the law of the earth, no matter what.

So what then is the psi of the tire and the outside air?

Quote from: 29silhouette
Are you now saying a difference of more than 1 psi will cause a container to fail?
Can one more small breath cause a fully inflated  balloon to go bang?
What is your definition of 'fully inflated'?  Filled to the point of bursting, or filled with any amount of air at which it contains a greater psi than the outside air?

If I add one psi to a small metal container with 3 psi in an environment of 2 psi, bringing it to 4, will it explode?
Title: Re: Space Flight
Post by: Rama Set on June 20, 2013, 05:58:05 AM
Logical and simple, what more could you want?

Something that does not disagree with his preconceived notions. This thread is like a goldmine for ignorance, I now understand why even the other FE'ers don't associate with Sceptimatic.

Yeah, even after 43 pages of being shown exactly why he's wrong, and providing his own examples which (accidentally) show him to be wrong, scepti still believes he's "100% right".
That's because I am 100% right.
This isn't arrogance on my part, it's simply a stance, because I know for a fact I am correct.

You haven't supplied even a single piece of evidence and yet you know you are 100% correct? Very funny.

Sceptimatic, who believes that we can create a machine that can withstand over 100 MPa and yet we can't build a machine that can withstand 100 kPa.
We can create what we like, material wise.
What we cannot do, is create an absolute vacuum.

Which is completely irrelevant as there is no such thing as an absolute vacuum.
On earth you are correct.

And in space. Even in deep space there are atoms and sub atomic particles floating around.
Nope. There's nothing in the space above us.Outside of our dome, I mean.

Why hasn't the some exploded like you say everything should when exposed to a vacuum?
Title: Re: Space Flight
Post by: Rama Set on June 20, 2013, 06:34:38 AM

Quote from: Rama Set
Why hasn't the some exploded like you say everything should when exposed to a vacuum?
A vacuum is matter less, there is no suction.
The vacuum we create on earth, is due to pressure being evacuated.
This is irrelevant in space, unless there was pressure in space.

Suction is created by a difference in pressure, so if there is no pressure in space it has 0 psi, therefore it creates suction. If you do not agree with this, then please tell me why space would suck gas out of a rocket.
Title: Re: Space Flight
Post by: Rama Set on June 20, 2013, 06:46:37 AM

Quote from: Rama Set
Why hasn't the some exploded like you say everything should when exposed to a vacuum?
A vacuum is matter less, there is no suction.
The vacuum we create on earth, is due to pressure being evacuated.
This is irrelevant in space, unless there was pressure in space.

Suction is created by a difference in pressure, so if there is no pressure in space it has 0 psi, therefore it creates suction. If you do not agree with this, then please tell me why space would suck gas out of a rocket.
There is no suction.We use suction because we see things as being sucked but the truth is, it's being pushed out as far as earth goes.
In the vacuum of space, it's matter less and up against nothing pushing into it.

Sucking, pushing the effect is the same.  There is a pressure difference between your vacuum and the dome.  Why hasn't it shattered like you have maintained it should for pages and pages?
Title: Re: Space Flight
Post by: Rama Set on June 20, 2013, 06:53:13 AM

Quote from: Rama Set
Why hasn't the some exploded like you say everything should when exposed to a vacuum?
A vacuum is matter less, there is no suction.
The vacuum we create on earth, is due to pressure being evacuated.
This is irrelevant in space, unless there was pressure in space.

Suction is created by a difference in pressure, so if there is no pressure in space it has 0 psi, therefore it creates suction. If you do not agree with this, then please tell me why space would suck gas out of a rocket.
There is no suction.We use suction because we see things as being sucked but the truth is, it's being pushed out as far as earth goes.
In the vacuum of space, it's matter less and up against nothing pushing into it.

Sucking, pushing the effect is the same.  There is a pressure difference between your vacuum and the dome.  Why hasn't it shattered like you have maintained it should for pages and pages?
Why hasn't what shattered?

The dome of the heavens.
Title: Re: Space Flight
Post by: DuckDodgers on June 20, 2013, 07:01:17 AM
The dome talk should probably be left in that topic and out of here.   
Title: Re: Space Flight
Post by: Rama Set on June 20, 2013, 07:04:08 AM

Quote from: Rama Set
Why hasn't the some exploded like you say everything should when exposed to a vacuum?
A vacuum is matter less, there is no suction.
The vacuum we create on earth, is due to pressure being evacuated.
This is irrelevant in space, unless there was pressure in space.

Suction is created by a difference in pressure, so if there is no pressure in space it has 0 psi, therefore it creates suction. If you do not agree with this, then please tell me why space would suck gas out of a rocket.
There is no suction.We use suction because we see things as being sucked but the truth is, it's being pushed out as far as earth goes.
In the vacuum of space, it's matter less and up against nothing pushing into it.

Sucking, pushing the effect is the same.  There is a pressure difference between your vacuum and the dome.  Why hasn't it shattered like you have maintained it should for pages and pages?
Why hasn't what shattered?

The dome of the heavens.
And this is where me and you end this conversation.
Anyone else want to take the piss, you follow this prick into the bin.

Whats wrong?  I am just applying your own theories.  I have not been rude and I am not taking the piss.  Even though I disagree with you, I am trying to be respectful.  You calling me names does not make it easy, but I will continue to be respectful anyway.
Title: Re: Space Flight
Post by: Rama Set on June 20, 2013, 07:16:51 AM
The dome talk should probably be left in that topic and out of here.

Sorry, he brought it up here.  I will leave it alone now.


Quote from: Rama Set
Why hasn't the some exploded like you say everything should when exposed to a vacuum?
A vacuum is matter less, there is no suction.
The vacuum we create on earth, is due to pressure being evacuated.
This is irrelevant in space, unless there was pressure in space.

Suction is created by a difference in pressure, so if there is no pressure in space it has 0 psi, therefore it creates suction. If you do not agree with this, then please tell me why space would suck gas out of a rocket.
There is no suction.We use suction because we see things as being sucked but the truth is, it's being pushed out as far as earth goes.
In the vacuum of space, it's matter less and up against nothing pushing into it.

Sucking, pushing the effect is the same.  There is a pressure difference between your vacuum and the dome.  Why hasn't it shattered like you have maintained it should for pages and pages?
Why hasn't what shattered?

The dome of the heavens.
And this is where me and you end this conversation.
Anyone else want to take the piss, you follow this prick into the bin.

Whats wrong?  I am just applying your own theories.  I have not been rude and I am not taking the piss.  Even though I disagree with you, I am trying to be respectful.  You calling me names does not make it easy, but I will continue to be respectful anyway.
If you genuinely want to find stuff out then use your loaf and read what I've put and stop twisting it. This isn't a courtroom, trying to catch people out.

I'm up against a barrage of you people and I try to answer all of you, so I don't need twisty comments to add to the work load.
If you want to play the game, I'm willing. If you want to look good in front of your forum associates, then you can do one, as far as I'm concerned.
It's up to you.

Quote from: Rama Set
Why hasn't the some exploded like you say everything should when exposed to a vacuum?
A vacuum is matter less, there is no suction.
The vacuum we create on earth, is due to pressure being evacuated.
This is irrelevant in space, unless there was pressure in space.

Suction is created by a difference in pressure, so if there is no pressure in space it has 0 psi, therefore it creates suction. If you do not agree with this, then please tell me why space would suck gas out of a rocket.
There is no suction.We use suction because we see things as being sucked but the truth is, it's being pushed out as far as earth goes.
In the vacuum of space, it's matter less and up against nothing pushing into it.

Sucking, pushing the effect is the same.  There is a pressure difference between your vacuum and the dome.  Why hasn't it shattered like you have maintained it should for pages and pages?
Why hasn't what shattered?

The dome of the heavens.
And this is where me and you end this conversation.
Anyone else want to take the piss, you follow this prick into the bin.

Whats wrong?  I am just applying your own theories.  I have not been rude and I am not taking the piss.  Even though I disagree with you, I am trying to be respectful.  You calling me names does not make it easy, but I will continue to be respectful anyway.
If you genuinely want to find stuff out then use your loaf and read what I've put and stop twisting it. This isn't a courtroom, trying to catch people out.

I'm up against a barrage of you people and I try to answer all of you, so I don't need twisty comments to add to the work load.
If you want to play the game, I'm willing. If you want to look good in front of your forum associates, then you can do one, as far as I'm concerned.
It's up to you.

I have not twisted anything.  I have applied your own theories to your own ideas.  If I have got it wrong, feel free to correct me, but don't get angry with me and call me names.
Title: Re: Space Flight
Post by: Scintific Method on June 20, 2013, 06:37:06 PM
If you genuinely want to find stuff out then use your loaf...

I do that quite a bit, believe it or not. I have an inquisitive mind and enjoy doing experiments. When I read something, be it in these fora or in the pages of a scientific text, I like to test it out and see if it works (if it is practical for me to do so at least). So far the scientific texts are winning; FET has yet to score a single point.

...and read what I've put and stop twisting it.

Are you saying we should ignore all of science so far (even though it is backed up be repeatable experiments), and listen solely to your ideas (even though they are not)? That is what it sounds like you are saying, but I just wanted to make sure I wasn't twisting your words.
Title: Re: Space Flight
Post by: 29silhouette on June 20, 2013, 08:40:15 PM

Quote from: 29silhouette
What is your definition of 'fully inflated'?  Filled to the point of bursting, or filled with any amount of air at which it contains a greater psi than the outside air?

Fully inflated to the point of elasticity breakdown.

So if a container is not fully inflated, but contains more than 1 psi difference than the surrounding atmosphere, then it won't burst.  Agreed?

Quote from: 29silhouette
If I add one psi to a small metal container with 3 psi in an environment of 2 psi, bringing it to 4, will it explode?
It depends on the strength of the container and its safe containment pressure.
Indeed.

Now about that truck tire.  If it's a 100 psi tire inflated to 100 psi, the atmosphere is 14.7 psi, and they're 'equalized' as you claim, what is the psi of each one?

Nope. There's nothing in the space above us.Outside of our dome, I mean.
If there's air pressure inside the dome and vacuum outside, why doesn't it explode outward?
Title: Re: Space Flight
Post by: Galactian on June 21, 2013, 01:25:51 AM
Quote from: 29silhouette
If there's air pressure inside the dome and vacuum outside, why doesn't it explode outward?
Because a dome is the strongest/ possible structure we can have to hold anything pressure wise.
The domes density is strongest at the bottom, just as a sky scrapers density is strongest at its foundation.

What evidence suggests there is a dome in the first, and why couldn't we create such a chamber on Earth - just miniaturized?

I also find it hard to follow your logic w/ vacuums. A vacuum, by definition, is an area of zero matter. An object floating inside a vacuum is experiencing exactly zero force from the outside; thus, the only force acting on the object is from the pressure within which, for something like a rocket, would be atmospheric pressure.

You seem to be implying that a rocket's structure cannot withstand 14.7 psi. If a tire can hold a pressure difference of more than 14.7 psi (the tire being at 30-40 psi, outside at 14.7 psi -- difference being greater than 14.7 psi), why can't a rocket that is designed to withstand far higher pressure differences? Remember that vacuums aren't physics-breaking objects. They don't have some special attribute which makes them irresistible.

Hell, you're lungs create a pretty good vacuum inside your body on a regular basis, and they are far less durable than rocket crafts.
Title: Re: Space Flight
Post by: Manarq on June 21, 2013, 04:09:52 AM
It's you that doesn't understand it all but you are too arrogant and mainstream viewed to even dare admit you are wrong and I'm right, because after all, I am scepti the tin foil hat nutter aren't I. ;)

I'm correct and you are incorrect and I know this 100% not 99.9%......100%.
Out of interest what have you done, apart from thinking really hard, to prove that you are 100% correct?

Have you designed and conducted a single experiment with the aim of disproving your ideas and if so could you put the details here.
Title: Re: Space Flight
Post by: Scintific Method on June 21, 2013, 04:13:33 AM
Sceptimatic, I can explain pressure in a way that actually makes sense and matches real world observations perfectly. Your explanations, as imaginative as they are, do neither of these things. They do not make intuitive or logical sense, and they do not match real world observations. This is not meant as a dig at you, I'm just making an observation.
Title: Re: Space Flight
Post by: DuckDodgers on June 21, 2013, 04:54:24 AM
Hold on, I think I might have just had an epiphany in what Scepti is trying to say, if I'm wrong just tell me because I'm not trying to twist your words around.  It sounds like he is saying that a tire inflated to 100 psi has the same force both inside and outside acting on it.  That the local atmospheric pressure on the container, i.e. the air directly in contact with the outside of the container, has increased to counter the pressure inside the container.  Or maybe that the container expands and creates more surface area on the outside for the atmospheric pressure to work on.  Am I getting close to your thinking Scepti?
Title: Re: Space Flight
Post by: Manarq on June 21, 2013, 05:46:16 AM
Hold on, I think I might have just had an epiphany in what Scepti is trying to say, if I'm wrong just tell me because I'm not trying to twist your words around.  It sounds like he is saying that a tire inflated to 100 psi has the same force both inside and outside acting on it.  That the local atmospheric pressure on the container, i.e. the air directly in contact with the outside of the container, has increased to counter the pressure inside the container.  Or maybe that the container expands and creates more surface area on the outside for the atmospheric pressure to work on.  Am I getting close to your thinking Scepti?
Thank you lord , finally someone with logic.
Absolutely correct Duck.

And what attracts these forces? Magnets? Magic? The Force? Why is the air suddenly thicker around the tire? Why is this not measurable?

Obvious nonsense.
You need logic to figure it out and you need to read and absorb everything I've said instead of discarding it as rubbish.
Once you get past that, you can learn how wrong you are about atmospheric pressure and it's strength.
This should be easy enough for you to test, a couple of gauges to measure the pressure being exerted on the outside surface of the tire by the atmosphere as you pump the tire up.

As usual I look forward to you posting the results.
Title: Re: Space Flight
Post by: DuckDodgers on June 21, 2013, 05:59:15 AM
Hold on, I think I might have just had an epiphany in what Scepti is trying to say, if I'm wrong just tell me because I'm not trying to twist your words around.  It sounds like he is saying that a tire inflated to 100 psi has the same force both inside and outside acting on it.  That the local atmospheric pressure on the container, i.e. the air directly in contact with the outside of the container, has increased to counter the pressure inside the container.  Or maybe that the container expands and creates more surface area on the outside for the atmospheric pressure to work on.  Am I getting close to your thinking Scepti?
Thank you lord , finally someone with logic.
Absolutely correct Duck.
Okay,  so now that we have that bit settled,  what about containers that don't expand?  The last time I saw a full propane tanknext to an empty one,  I couldn't tell which was which.  So without a significant increase in the outside surface area, how does the atmospheric pressure increase to counter the increased internal pressure?
Title: Re: Space Flight
Post by: DuckDodgers on June 21, 2013, 06:21:02 AM
My own logic is telling me that 14.7 psi is 14.7 psi and if you take air out of the atmosphere,  you drop the pressure.   My logic tells me that buildings are built to withstand tons and tons of force acting on them,  so pressure containers should be able to built to do this as well.   My logic tells me that submarines can handle deep sea pressures,  but they will fail if they dive too low because of the massive pressure,  and that they would be most likely to fail at seams in the vessel.   My logic tells me that people can't survive in 300 psi environments,  but submarines can,  so at no point can the inside of a submarine be 300 psi.   My logic also tells me that pressure is constant throughout a pressure container.   Every bit of my logic is working against your reasoning.
Title: Re: Space Flight
Post by: markjo on June 21, 2013, 06:30:22 AM
Arguing against mainstream science is always going to be looked on as arrogant with you lot and I don't care one jot, because I'm not easily backed into a corner or intimidated and I'm confident in what I say, so you take that how you want to.
Arguing against the mainstream, in and of itself, is not necessarily a bad thing.  The mainstream definitely needs people to keep it honest.  However, in order to properly argue against the mainstream, you have to understand the mainstream well enough to be able to argue against it on its level, not yours.  Mainstream science has very specific terms for very specific phenomena.  You will not be able to upset the mainstream if you misuse these terms or use childlike explanations.

Seriously, take the time to learn and understand what we're trying to teach you about these terms and concepts.  You don't have to believe or accept them, but you really do need to learn and understand them so that we can have an adult conversation.  Kiddie physics won't change the mainstream.
Title: Re: Space Flight
Post by: DuckDodgers on June 21, 2013, 07:10:51 AM
I have a grasp of your logic.   I also know your logic is flawed.   By your logic,  pressure chambers just need to be thick.   By my logic,  they need a strong shape to disperse forces.   By your logic pressures are equal throughout a container except on the walls.   By my logic,  pressures are equal throughout a container regardless of where.   
Title: Re: Space Flight
Post by: Manarq on June 21, 2013, 07:22:14 AM
Sceptimatic I'm curious now, does this mean that in your view no-one can build a vacuum chamber?
Title: Re: Space Flight
Post by: markjo on June 21, 2013, 07:41:39 AM
If any person argues a point using the main stream view...it plays into their hands, because they baffle you with bull shit, using ridiculous equations that do not require them to simply grasp the logic of something.

Applying those forces to building stuff requires math. But figuring out the bullshit behind certain stuff, such as rockets working in a vacuum, requires common sense and logic in very simple terms.

The thing is that mainstream science realizes that what you think is logic isn't always the case.  Things are not always as simple as they seem.  When you explain something to a child, you often need to over simplify, and even tell little white lies.  When a small child asks where babies come from, do you explain the whole process of sperm and egg production, the copulation process, the relevant anatomy, etc., or do you say that babies come from mommy's tummy? 

It's the same thing here.  Rather than trying to understand the physics involved in Newton's laws and pressure dynamics, you are saying that we should just accept your "mommy's tummy" explanation.
Title: Re: Space Flight
Post by: Manarq on June 21, 2013, 08:04:18 AM
If any person argues a point using the main stream view...it plays into their hands, because they baffle you with bull shit, using ridiculous equations that do not require them to simply grasp the logic of something.

Applying those forces to building stuff requires math. But figuring out the bullshit behind certain stuff, such as rockets working in a vacuum, requires common sense and logic in very simple terms.

The thing is that mainstream science realizes that what you think is logic isn't always the case.  Things are not always as simple as they seem.  When you explain something to a child, you often need to over simplify, and even tell little white lies.  When a small child asks where babies come from, do you explain the whole process of sperm and egg production, the copulation process, the relevant anatomy, etc., or do you say that babies come from mommy's tummy? 

It's the same thing here.  Rather than trying to understand the physics involved in Newton's laws and pressure dynamics, you are saying that we should just accept your "mommy's tummy" explanation.
You don't have to accept anything I say. Most never do anyway.
I don't care whether you accept it or not. All i know is, people who are viewing are appreciating my simple logical explanations rather than have their heads filled with bull shit equations to explain something that logically can be grasped in a simplified manner.

If there's no doubt in your mind that I'm wrong and you are right and that you know I will not be swayed, then your participation with me should be over for this topic.
It isn't because you do have doubt about it in your mind and you are questioning it, whilst trying to still make out that my logic is flawed, when I know 100% that I am correct.
Again how do you know you are 100% correct? What have you done to prove this apart from thinking about it?
Title: Re: Space Flight
Post by: Manarq on June 21, 2013, 08:09:19 AM
Sceptimatic I'm curious now, does this mean that in your view no-one can build a vacuum chamber?
Anybody can build a chamber to evacuate air from. You can build one out of a thin plastic bottle but you would only be able to evacuate a minute portion of air before the bottle creases.
What you cannot do, is make a chamber that you can evacuate all air molecules from.
Many people through this and other threads have told you that the vacuum of space isn't a perfect vacuum and that we can actually create a better vacuum here on Earth than actually exists in space.
Title: Re: Space Flight
Post by: DuckDodgers on June 21, 2013, 08:11:54 AM
Arches are designed to deflect the forces down their arms, that is correct,  but compressed air cylinders aren't designed because of expansion,  but rather to disperse a force across the entire container as well as to hold as much air as possible in a convenient to use shape.   They would probably be spherical if they didn't have any constraints other than holding pressurized gas.  Increased surface area cannot account for a pressure container,  and I don't even know why we are still having this discussion since we know what pressure is, a force applied over an area.   Everytime you drive a car over a bridge we can see that this can be constructed to withstand pressure.   We know that building materials are tested before use,  and one popular test is putting a length of material across a gap and applying a force in the center to see the deflection and break limits.   That test is applying a pressure to the material and I can guarantee that it takes morethan 14.7 pounds per square inch to break a lot of building materials.
Title: Re: Space Flight
Post by: Manarq on June 21, 2013, 08:25:58 AM
Sceptimatic I'm curious now, does this mean that in your view no-one can build a vacuum chamber?
Anybody can build a chamber to evacuate air from. You can build one out of a thin plastic bottle but you would only be able to evacuate a minute portion of air before the bottle creases.
What you cannot do, is make a chamber that you can evacuate all air molecules from.
Many people through this and other threads have told you that the vacuum of space isn't a perfect vacuum and that we can actually create a better vacuum here on Earth than actually exists in space.
You have never been in space. No one has, so that's a bold statement.
A perfect vacuum cannot be made on earth, which should tell you that everything man made to create it, would end up in disaster.
I've been thinking about space and it's makeup really hard, and using my logic I've decided it is a vacuum. What more proof do you need?
Title: Re: Space Flight
Post by: Manarq on June 21, 2013, 08:50:02 AM

I've been thinking about space and it's makeup really hard, and using my logic I've decided it is a vacuum. What more proof do you need?
Ok, we will have space outside the dome as a vacuum, I'm happy with that.
Now using your logic what happens if you put a sealed container in a perfect vacuum?
Title: Re: Space Flight
Post by: DuckDodgers on June 21, 2013, 09:19:11 AM
Arches are designed to deflect the forces down their arms, that is correct,  but compressed air cylinders aren't designed because of expansion,  but rather to disperse a force across the entire container as well as to hold as much air as possible in a convenient to use shape.   They would probably be spherical if they didn't have any constraints other than holding pressurized gas.  Increased surface area cannot account for a pressure container,  and I don't even know why we are still having this discussion since we know what pressure is, a force applied over an area.   Everytime you drive a car over a bridge we can see that this can be constructed to withstand pressure.   We know that building materials are tested before use,  and one popular test is putting a length of material across a gap and applying a force in the center to see the deflection and break limits.   That test is applying a pressure to the material and I can guarantee that it takes morethan 14.7 pounds per square inch to break a lot of building materials.
When you first grasped my logic, I thought "great, finally someone has switched on their logic machine" and now you have completely crumbled it all and are back to square one.
It's a shame you can't grasp it but what the hell. I'm sure someones light bulb will come on sooner or later.

I'm correct, 100%.
You're probably in the range of 40% correct.  It seems like rigid pressure vessels,  like submarines,  shouldn't be some to exist by your logic.  I'd love to see your attempt to quantify your belief and develop a model that can be used for design purposes.
Title: Re: Space Flight
Post by: Manarq on June 21, 2013, 09:28:06 AM

I've been thinking about space and it's makeup really hard, and using my logic I've decided it is a vacuum. What more proof do you need?
Ok, we will have space outside the dome as a vacuum, I'm happy with that.
Now using your logic what happens if you put a sealed container in a perfect vacuum?
It cannot be done.
So how can there be a dome covering the Earth creating a sealed environment with atmosphere on the inside and a vacuum on the outside?
Title: Re: Space Flight
Post by: DuckDodgers on June 21, 2013, 09:34:34 AM
Arches are designed to deflect the forces down their arms, that is correct,  but compressed air cylinders aren't designed because of expansion,  but rather to disperse a force across the entire container as well as to hold as much air as possible in a convenient to use shape.   They would probably be spherical if they didn't have any constraints other than holding pressurized gas.  Increased surface area cannot account for a pressure container,  and I don't even know why we are still having this discussion since we know what pressure is, a force applied over an area.   Everytime you drive a car over a bridge we can see that this can be constructed to withstand pressure.   We know that building materials are tested before use,  and one popular test is putting a length of material across a gap and applying a force in the center to see the deflection and break limits.   That test is applying a pressure to the material and I can guarantee that it takes morethan 14.7 pounds per square inch to break a lot of building materials.
When you first grasped my logic, I thought "great, finally someone has switched on their logic machine" and now you have completely crumbled it all and are back to square one.
It's a shame you can't grasp it but what the hell. I'm sure someones light bulb will come on sooner or later.

I'm correct, 100%.
You're probably in the range of 40% correct.  It seems like rigid pressure vessels,  like submarines,  shouldn't be some to exist by your logic.  I'd love to see your attempt to quantify your belief and develop a model that can be used for design purposes.
No container on earths crust can withstand a vacuum or the deepest part of the ocean. It cannot be done.
I already linked to you the information about the sub that reached the Challenger Deep,  the deepest part of the ocean.   And there have been 3 other visits to that depth.   That is over 10 km below the surface.  People went down and came back to tell the tale,  so I'd say their vessel survived this crushing pressure.
Title: Re: Space Flight
Post by: markjo on June 21, 2013, 09:44:00 AM
I don't care whether you accept it or not. All i know is, people who are viewing are appreciating my simple logical explanations rather than have their heads filled with bull shit equations to explain something that logically can be grasped in a simplified manner.
What makes you believe that the things that rockets and vacuums are simple and logical?

Quote
It isn't because you do have doubt about it in your mind and you are questioning it, whilst trying to still make out that my logic is flawed, when I know 100% that I am correct.
I'm not quite sure what you're trying to say here.  Are you admitting that your logic is flawed?  ???
Title: Re: Space Flight
Post by: Googleotomy on June 21, 2013, 09:54:28 AM
Quote from: DuckDodgers
I already linked to you the information about the sub that reached the Challenger Deep,  the deepest part of the ocean.   And there have been 3 other visits to that depth.   That is over 10 km below the surface.  People went down and came back to tell the tale,  so I'd say their vessel survived this crushing pressure.
Yes and shuttles and rockets have been into space and to the moon and stuff.
If you think these subs have went to the deepest part of the ocean then you are so naive, it's actually not funny.
I can understand a kid or someone who takes no notice of what's and why's and wherefores but you are supposed to have some scientific savvy like others and yet you swallow so much crap that surely your alarm bells must sound.
If not, you must be scared to have your thoughts dashed so you just go along with the crap that they dish out.

Seriously, common sense alone should tell you why those subs didn't go to where they say they did.
Hands up how many believe that crap about the subs?

I, too, am not quite sure as to what you are saying.
http://en.wikipedia.org/wiki/Mariana_Trench (http://en.wikipedia.org/wiki/Mariana_Trench)

Or is this just another typical FE reply that any thing on wikipedia is fake ?
Or that any thing or any source of information that disagrees with FET is fake ?
Or that any thing or any source of information that disagrees with what FE "thinks" or "believes" is fake ?
I suppose that wikipedia is just one more member of "The Round Earth Conspiracy" ?

Or maybe : Paraphrasing the words of Will Rogers) : "All I know is what I read in the papers Internet and that's my excuse for ignorance."  ;D
Title: Re: Space Flight
Post by: Antonio on June 21, 2013, 10:01:46 AM

I've been thinking about space and it's makeup really hard, and using my logic I've decided it is a vacuum. What more proof do you need?
Ok, we will have space outside the dome as a vacuum, I'm happy with that.
Now using your logic what happens if you put a sealed container in a perfect vacuum?
It cannot be done.
Prove it. Your claim, your evidence. Enough theory and  more real world facts.
And by the way show us the calculated answers to my previous question.
Title: Re: Space Flight
Post by: Googleotomy on June 21, 2013, 10:11:50 AM
Quote from: DuckDodgers
I already linked to you the information about the sub that reached the Challenger Deep,  the deepest part of the ocean.   And there have been 3 other visits to that depth.   That is over 10 km below the surface.  People went down and came back to tell the tale,  so I'd say their vessel survived this crushing pressure.
Yes and shuttles and rockets have been into space and to the moon and stuff.
If you think these subs have went to the deepest part of the ocean then you are so naive, it's actually not funny.
I can understand a kid or someone who takes no notice of what's and why's and wherefores but you are supposed to have some scientific savvy like others and yet you swallow so much crap that surely your alarm bells must sound.
If not, you must be scared to have your thoughts dashed so you just go along with the crap that they dish out.

Seriously, common sense alone should tell you why those subs didn't go to where they say they did.
Hands up how many believe that crap about the subs?

I, too, am not quite sure as to what you are saying.
http://en.wikipedia.org/wiki/Mariana_Trench (http://en.wikipedia.org/wiki/Mariana_Trench)

Or is this just another typical FE reply that any thing on wikipedia is fake ?
Or that any thing or any source of information that disagrees with FET is fake ?
Or that any thing or source of information that disagrees with what FE "thinks" or "believes" is fake ?
Look at the depth and look at the sub, the tonnage...everything and then think about the amount of air he would need for that trip down.
It's absolute bollocks and if you can't see that, then I can't help you. Just carry on believing it.

Thank you for your fine forensic anaylysis Mr. Sceptimatic. I assume you have Doctor's degrees in oceanography , physics and engineering et cetera  and Post-Graduate studies and experience in those subjects  to back up your statements.  ;D

"Just go with what you believe. I'm not arsed whether you believe it or not. It doesn't affect me in any way.
One day the light bulb may come on, you never know."

I sometimes wonder if Sceptimatic has had a power outage ?  ???
Title: Re: Space Flight
Post by: Antonio on June 21, 2013, 10:16:50 AM

I've been thinking about space and it's makeup really hard, and using my logic I've decided it is a vacuum. What more proof do you need?
Ok, we will have space outside the dome as a vacuum, I'm happy with that.
Now using your logic what happens if you put a sealed container in a perfect vacuum?
It cannot be done.
Prove it. Your claim, your evidence. Enough theory and  more real world facts.
And by the way show us the calculated answers to my previous question.
Just go with what you believe. I'm not arsed whether you believe it or not. It doesn't affect me in any way.
One day the light bulb may come on, you never know.
That's not the point.
"Don't accept anything without questioning it" does apply to your claims too. I'm questioning them and gave you a very easy mean to substanciate them, but I'm still waiting for answers others than " because I'm 100% correct" or "I'm right".
 
Title: Re: Space Flight
Post by: markjo on June 21, 2013, 10:21:34 AM
My conversation with you ends here.
No need to reply.
I'm sorry if I'm asking questions that are too difficult for you to answer, but sometimes life hands you tough questions that you just can't walk away from.  Good luck when that happens to you.
Title: Re: Space Flight
Post by: Antonio on June 21, 2013, 10:24:02 AM

I've been thinking about space and it's makeup really hard, and using my logic I've decided it is a vacuum. What more proof do you need?
Ok, we will have space outside the dome as a vacuum, I'm happy with that.
Now using your logic what happens if you put a sealed container in a perfect vacuum?
It cannot be done.
Prove it. Your claim, your evidence. Enough theory and  more real world facts.
And by the way show us the calculated answers to my previous question.
Just go with what you believe. I'm not arsed whether you believe it or not. It doesn't affect me in any way.
One day the light bulb may come on, you never know.
That's not the point.
"Don't accept anything without questioning it" does apply to your claims too. I'm questioning them and gave you a very easy mean to substanciate them, but I'm still waiting for answers others than " because I'm 100% correct" or "I'm right".
If you can't logically see by the explanations I've spent this entire topic giving out, then you are never going to get it, or you have no intention of.
Come back to me when you want to use your my logic.
Just fixed  the previous sentence.
I'm not asking for your logic, but for some bit of truth in your beliefs. You can't give it? that's fine.
Title: Re: Space Flight
Post by: DuckDodgers on June 21, 2013, 10:49:47 AM
Quote from: DuckDodgers
I already linked to you the information about the sub that reached the Challenger Deep,  the deepest part of the ocean.   And there have been 3 other visits to that depth.   That is over 10 km below the surface.  People went down and came back to tell the tale,  so I'd say their vessel survived this crushing pressure.
Yes and shuttles and rockets have been into space and to the moon and stuff.
If you think these subs have went to the deepest part of the ocean then you are so naive, it's actually not funny.
I can understand a kid or someone who takes no notice of what's and why's and wherefores but you are supposed to have some scientific savvy like others and yet you swallow so much crap that surely your alarm bells must sound.
If not, you must be scared to have your thoughts dashed so you just go along with the crap that they dish out.

Seriously, common sense alone should tell you why those subs didn't go to where they say they did.
Hands up how many believe that crap about the subs?
I have no reason to believe these dives did not occur the way they described.   Sure the design of the submersible would be an extraordinary feat and need to withstand incredible pressures,  I believe I saw at 15k psi figure if I remember correctly.   This is no ordinary undertaking and is evidenced by the very small number of dives to this location despite it's fame of being the deepest sea floor.  Design and rebreathers can account for much of what you have issues with.

What is the safety limit on dives by your logic and opinion?  Just how deep can we go before hitting the wall of impossibility?
Title: Re: Space Flight
Post by: Googleotomy on June 21, 2013, 11:04:46 AM
Something else for FE to cry "Fake ! It's probably just a small scale model used in some science fiction movie and photoshopped against a background ! "

http://en.wikipedia.org/wiki/File:Bathyscaphe_Trieste.jpg (http://en.wikipedia.org/wiki/File:Bathyscaphe_Trieste.jpg)
Title: Re: Space Flight
Post by: Googleotomy on June 21, 2013, 11:12:43 AM
You shouldn't need any more proof than I've given.

You haven't given any.

I'm just one of many, but I have seen exactly zilch . ??? There seems to be plenty of proof from the other side........But of course, it can be discounted since  it is all from sources that are members of "The Round Earth Conspiracy."
Title: Re: Space Flight
Post by: Googleotomy on June 21, 2013, 11:56:46 AM
Something else for FE to cry "Fake ! It's probably just a small scale model used in some science fiction movie and photoshopped against a background ! "

http://en.wikipedia.org/wiki/File:Bathyscaphe_Trieste.jpg (http://en.wikipedia.org/wiki/File:Bathyscaphe_Trieste.jpg)
It doesn't matter what the sub is. It didn't go to the trench. It's impossible. We are talking 7 miles of deep ocean. ::)

Simple answer . :
It DID go to the trench.
It WAS possible. I'm sorry, but I really have to tell you that.  :'(

Why ?
Because it was very carefully  DESIGNED ........  AND...... It was very carefully CONSTRUCTED that way  to withstand the pressures and able to go down to 7 miles of deep ocean.

(Besides,  those old so-called "no-nothing" scientists and engineers had to DESIGN .......AND......CONTRUCT it that way to withstand the pressures and go down to 7 miles of deep ocean.)

If I remember correctly, James Cameron only had to go down about 2 1/2 miles to the wreck of the Titanic.

Sceptimatic Was that too deep, too, and it was obviously faked, too. ?  ???

This may be a startling revelation, but there are some people that are smarter than you and I, sceptimatic and know about how to make things such as Trieste .

Of course, I "know" that you don't "believe" that, sceptimatic.
Title: Re: Space Flight
Post by: DuckDodgers on June 21, 2013, 12:18:09 PM
A 5 inch thick steel pressure vessel they were in and it had glass windows.  ;D
A single small cone shaped plexi glass window,  whose thickness they hadn't commented but at most about the same thickness of the vessel.
Title: Re: Space Flight
Post by: sokarul on June 21, 2013, 01:15:29 PM
Don't forget James Cameron did it.
http://news.nationalgeographic.com/news/2012/03/120325-james-cameron-mariana-trench-challenger-deepest-returns-science-sub/ (http://news.nationalgeographic.com/news/2012/03/120325-james-cameron-mariana-trench-challenger-deepest-returns-science-sub/)

http://en.wikipedia.org/wiki/Deepsea_Challenger (http://en.wikipedia.org/wiki/Deepsea_Challenger)
Title: Re: Space Flight
Post by: Shmeggley on June 21, 2013, 04:47:11 PM
Quote from: DuckDodgers
I already linked to you the information about the sub that reached the Challenger Deep,  the deepest part of the ocean.   And there have been 3 other visits to that depth.   That is over 10 km below the surface.  People went down and came back to tell the tale,  so I'd say their vessel survived this crushing pressure.
Yes and shuttles and rockets have been into space and to the moon and stuff.
If you think these subs have went to the deepest part of the ocean then you are so naive, it's actually not funny.
I can understand a kid or someone who takes no notice of what's and why's and wherefores but you are supposed to have some scientific savvy like others and yet you swallow so much crap that surely your alarm bells must sound.
If not, you must be scared to have your thoughts dashed so you just go along with the crap that they dish out.

Seriously, common sense alone should tell you why those subs didn't go to where they say they did.
Hands up how many believe that crap about the subs?

I, too, am not quite sure as to what you are saying.
http://en.wikipedia.org/wiki/Mariana_Trench (http://en.wikipedia.org/wiki/Mariana_Trench)

Or is this just another typical FE reply that any thing on wikipedia is fake ?
Or that any thing or any source of information that disagrees with FET is fake ?
Or that any thing or source of information that disagrees with what FE "thinks" or "believes" is fake ?
Look at the depth and look at the sub, the tonnage...everything and then think about the amount of air he would need for that trip down.
It's absolute bollocks and if you can't see that, then I can't help you. Just carry on believing it.

Thank you for your fine forensic anaylysis Mr. Sceptimatic. I assume you have Doctor's degrees in oceanography , physics and engineering et cetera  and Post-Graduate studies and experience in those subjects  to back up your statements.  ;D

"Just go with what you believe. I'm not arsed whether you believe it or not. It doesn't affect me in any way.
One day the light bulb may come on, you never know."

I sometimes wonder if Sceptimatic has had a power outage ?  ???

Sceptimatic is more like somebody who hasn't paid their power bill in 10 years because he thinks David Letterman wants to steal his brainwaves through the electrical socket.

Relax Sceptimatic, I didn't say you were that guy, just more like.

Seriously though, I'm 100% right, because I have better logic.
Title: Re: Space Flight
Post by: 29silhouette on June 21, 2013, 06:58:38 PM
Quote from: 29silhouette
So if a container is not fully inflated, but contains more than 1 psi difference than the surrounding atmosphere, then it won't burst.  Agreed?

There is "never" any difference, it's all immediately equalised. It's just a case of how much stress the walls of the container can resist an equal crush from all areas inside and out.
So a container with 15 psi in an environment of 0.01 psi will not burst because:
A. both the container and surrounding environment are now 15 psi.
or
B. both the container and surrounding environment are now 0.01 psi.

Which is it?  *edit- upon further reading I guess it's A.  Apparently enough air will come rushing in out of the .01 psi environment to create a 15 psi layer around the container.

Quote from: 29silhouette
Now about that truck tire.  If it's a 100 psi tire inflated to 100 psi, the atmosphere is 14.7 psi, and they're 'equalized' as you claim, what is the psi of each one?
100 psi acting on the tyre alone. The air pressure will act against the vessel that took it, so it's equalised all the time and only the make up of the rubber and wire can determine when it breaches, because it's being crushed from all angles until the rubber "walls" starts to compress to a point of thinning out and the weakest point will be breached. allowing the air back into the atmosphere.
So both the inside of the tire and the outside atmosphere are now at 100 psi?

What if I have a truck tire with 100 psi next to a car tire with 30 psi?  Let's say 1 cm away.

*edit- What keeps the 100 psi layer around one tire from spreading to the 30 psi layer around the other tire, or even the 14.7 psi area in between?

Quote from: 29silhouette
If there's air pressure inside the dome and vacuum outside, why doesn't it explode outward?
Because a dome is the strongest/ possible structure we can have to hold anything pressure wise.
The domes density is strongest at the bottom, just as a sky scrapers density is strongest at its foundation.

Domes and curved structures are able to sustain excessive pressure against the outer curve.  A dome would hold back pressure from the outside, but would be unable to hold in as much pressure.  Not to mention one made of ice.

Ever notice how most dams are curved toward the reservoir behind it or at least straight?  Ever see one curved outward from the water?

Hold on, I think I might have just had an epiphany in what Scepti is trying to say, if I'm wrong just tell me because I'm not trying to twist your words around.  It sounds like he is saying that a tire inflated to 100 psi has the same force both inside and outside acting on it.  That the local atmospheric pressure on the container, i.e. the air directly in contact with the outside of the container, has increased to counter the pressure inside the container.  Or maybe that the container expands and creates more surface area on the outside for the atmospheric pressure to work on.  Am I getting close to your thinking Scepti?
Thank you lord , finally someone with logic.
Absolutely correct Duck.
I wondered the other day if this is what you were thinking of. 

What happens when I drive away?  How does the 30 psi layer surrounding my tire keep up?
Title: Re: Space Flight
Post by: icanbeanything on June 22, 2013, 09:52:26 AM
Something else for FE to cry "Fake ! It's probably just a small scale model used in some science fiction movie and photoshopped against a background ! "

http://en.wikipedia.org/wiki/File:Bathyscaphe_Trieste.jpg (http://en.wikipedia.org/wiki/File:Bathyscaphe_Trieste.jpg)
It doesn't matter what the sub is. It didn't go to the trench. It's impossible. We are talking 7 miles of deep ocean. ::)

You know, for someone who is so opposed to appeals to ridicule, you do love to ridicule others yourself.

It went 7 miles deep? Ridiculous! It can't be true.

Rockets working in a vacuum? Ridiculous! It can't be true.

You just tend to slap "impossible" stickers at completely arbitrary things, without actually knowing whether they're possible or not.
Title: Re: Space Flight
Post by: Puttah on June 22, 2013, 10:14:35 AM
Scepti, you have no problem with submarines going to shallower depths, right? Well, at which point does it become ridiculous? If the deepest trenches were 1 mile deep, would it still be impossible? What if they were 100ft deep?

This is why numbers are so powerful. They quantize the world, and it's a good thing because qualitative terms such as "very deep" can only go so far.
Title: Re: Space Flight
Post by: Rama Set on June 22, 2013, 04:51:22 PM
Please do.
Title: Re: Space Flight
Post by: Puttah on June 22, 2013, 08:42:04 PM
I don't discount numbers.
I only discount the numbers given out for space science and magical stuff and the way they are made to baffle the hell out of ordinary people.
It's the reason why I bring people down to the simple level but I have to drag them down screaming because their minds cannot contemplate simplistic logic, which is required to at least understand what everything is about.

Can electrical engineering and computer science be brought down to the simple level? These are just two topics that you don't believe are a part of the indoctrinated mainstream science. Can you describe these simply? No? Then why do you expect every physical phenomenon needs to have a simple answer?

To know why a sub cannot go to massive depths you need to know why there is sand on the beaches.
Sound crazy?
If it does, then I will stop right here.
Sure, but you've used a qualitative term once again. For someone that doesn't discount numbers, you sure seem to avoid them at all costs.
Title: Re: Space Flight
Post by: Puttah on June 23, 2013, 08:21:30 AM
I don't discount numbers.
I only discount the numbers given out for space science and magical stuff and the way they are made to baffle the hell out of ordinary people.
It's the reason why I bring people down to the simple level but I have to drag them down screaming because their minds cannot contemplate simplistic logic, which is required to at least understand what everything is about.

Can electrical engineering and computer science be brought down to the simple level? These are just two topics that you don't believe are a part of the indoctrinated mainstream science. Can you describe these simply? No? Then why do you expect every physical phenomenon needs to have a simple answer?

To know why a sub cannot go to massive depths you need to know why there is sand on the beaches.
Sound crazy?
If it does, then I will stop right here.
Sure, but you've used a qualitative term once again. For someone that doesn't discount numbers, you sure seem to avoid them at all costs.
To understand how things work, we don't need equations and numbers.
To make them work to our needs, efficiently and safely...that's when we need calculations.

Your claim was that submarines can't survive in the trenches based on nothing other than it being the deepest part of the oceans. So a natural question is, at what point do submarines fail? To understand how this works and to answer it, you need equations and numbers. You have provided neither which is evident since you ignored my hypothetical scenario of the ocean floor being shallower.
Title: Re: Space Flight
Post by: Puttah on June 23, 2013, 08:40:36 AM
Puttah:

Use your own common sense. I'm sure you can figure out why a sub cannot go to those depths. If not, then just carry on believing in fantasy.
I would have thought finding the reality and truth would be far better than simply asking me to provide you with calculation, when you can clearly do that yourself.
If you believe a sub can go to that depth after seeing the data on it and what was used then carry on, because I nor anyone else will convince you otherwise.

I'm sorry, but my common sense alone can't figure out whether a very sturdy metallic tank can withstand very large pressures. Your common sense is obviously superior to mine.
Title: Re: Space Flight
Post by: icanbeanything on June 23, 2013, 12:24:07 PM
Either use your common sense or go with their silly figures. The choice is entirely yours.

Pressure at the bottom of the Mariana Trench is almost 16,000 psi. Seems very high, until you check out industrial pressure containers and valves, which are designed to withstand pressures way above 150,000 psi (i.e. nearly ten times as much as at the bottom of the Mariana Trench).

Proves that human engineering can produce devices that could withstand the pressure at the bottom of the Mariana Trench, rather easily. This is as common sense as it can get.
Title: Re: Space Flight
Post by: Googleotomy on June 23, 2013, 06:00:28 PM
Puttah:

Use your own common sense. I'm sure you can figure out why a sub cannot go to those depths. If not, then just carry on believing in fantasy.
I would have thought finding the reality and truth would be far better than simply asking me to provide you with calculation, when you can clearly do that yourself.
If you believe a sub can go to that depth after seeing the data on it and what was used then carry on, because I nor anyone else will convince you otherwise.

I'm sorry, but my common sense alone can't figure out whether a very sturdy metallic tank can withstand very large pressures. Your common sense is obviously superior to mine.

In the days of wooden ships, some people's "common sense" said that iron ships wouldn't float and that iron ships would sink because their "common sense couldn't figure it out . "

icanbeanything Neither, You , I , nor anyone else is ever going to convince sceptimatic otherwise of anything else.  :D Might as well give it up as a lost cause.  :'(
Title: Re: Space Flight
Post by: Googleotomy on June 23, 2013, 07:00:19 PM
I don't discount numbers.
I only discount the numbers given out for space science and magical stuff and the way they are made to baffle the hell out of ordinary people.
It's the reason why I bring people down to the simple level but I have to drag them down screaming because their minds cannot contemplate simplistic logic, which is required to at least understand what everything is about.

Can electrical engineering and computer science be brought down to the simple level? These are just two topics that you don't believe are a part of the indoctrinated mainstream science. Can you describe these simply? No? Then why do you expect every physical phenomenon needs to have a simple answer?

To know why a sub cannot go to massive depths you need to know why there is sand on the beaches.
Sound crazy?
If it does, then I will stop right here.
Sure, but you've used a qualitative term once again. For someone that doesn't discount numbers, you sure seem to avoid them at all costs.
To understand how things work, we don't need equations and numbers.
To make them work to our needs, efficiently and safely...that's when we need calculations.

My studies in electrical engineering and electronics were at the elementary level.......But.....  I surely do wish that  those tyrants, (my instructors, that is  >:( ) , had known that equations  and numbers weren't needed on the tests and final exams in those subjects. It would have been a lot easier to pass them !   ;D

Sceptimatic You can probably mark me down as a lot denser than you, but I want to know how in the world can you get calculations without equations and numbers ?  ??? Oh, sorry about that !!!! Of course !!!! You don't need equations and numbers to get calculations in the Flat Earth World. Common sense would tell you that.

P.S. Is PBS on the Conspiracy list ? If not, put them on it . They have some "Space Flight"  programs coming on this week.  Better add Ohm and Kirchoff from my EE studies, too  They made those silly "Ohm's Law" and "Kirchoff's Law." .....Among with a lot of other silly laws by other silly scientists......
Title: Re: Space Flight
Post by: Antonio on June 24, 2013, 02:15:09 AM
Well said. Symetrically, you admit that you can't say "it cannot work" without the necessary calculations. Please can you share them ?
Title: Re: Space Flight
Post by: Antonio on June 24, 2013, 03:38:54 AM
Still avoiding the answer...Please share your calculations that show that for example Mr Piccard's "Trieste" cannot go to -10000m
Title: Re: Space Flight
Post by: Puttah on June 24, 2013, 04:00:49 AM
I said: "you do not need calculations to figure out the concept of the way something works", that doesn't mean you can simply build something and have it work, without the necessary calculations to make sure everything marries up.

Still avoiding the answer...Please share your calculations that show that for example Mr Piccard's "Trieste" cannot go to -10000m
I don't need calculations to know bull crap when I see it.

Hahaha oh the irony!

Maybe something was lost many years ago in that little head of yours.
Title: Re: Space Flight
Post by: Antonio on June 24, 2013, 04:01:38 AM
Still avoiding the answer...Please share your calculations that show that for example Mr Piccard's "Trieste" cannot go to -10000m
I don't need calculations to know bull crap when I see it.
Your opinion is irrelevant. You are debating here, trying to convince other people, hopefully giving some factual elements. Explanations like "I'm sure", "I'm right" or "believe me" are not facts. Some calculations are fine.
Basically the same I asked for few pages before.
Title: Re: Space Flight
Post by: icanbeanything on June 24, 2013, 04:02:18 AM
Still avoiding the answer...Please share your calculations that show that for example Mr Piccard's "Trieste" cannot go to -10000m
I don't need calculations to know bull crap when I see it.

I guess you completely skipped my comment:

Quote
Pressure at the bottom of the Mariana Trench is almost 16,000 psi. Seems very high, until you check out industrial pressure containers and valves, which are designed to withstand pressures way above 150,000 psi (i.e. nearly ten times as much as at the bottom of the Mariana Trench).

Proves that human engineering can produce devices that could withstand the pressure at the bottom of the Mariana Trench, rather easily. This is as common sense as it can get.
Title: Re: Space Flight
Post by: markjo on June 24, 2013, 11:07:10 AM
Still avoiding the answer...Please share your calculations that show that for example Mr Piccard's "Trieste" cannot go to -10000m
I don't need calculations to know bull crap when I see it.
Sceptimatic, your approach to scientific debate seems to be "I've made up my mind.  Don't try to confuse me with the facts."
Title: Re: Space Flight
Post by: 29silhouette on June 25, 2013, 06:35:06 PM
Just a few more things to clear up if you'd be so kind.

Why won't 100 psi of pressure against the side of the tire disperse into the surrounding 14.7 psi environment?  The tire expanded slightly and stopped, so how does the air against the outside continue to remain at 100 psi with no physical barrier between it and the 14.7 psi environment?


Since you claim it's the equalized air pressure on each side hammering on the container wall that causes it to fail, what if I have a container with 7psi in a 1 psi environment?  That's only 7 psi.  I have plastic bottles in my kitchen containing 14.7 psi in 14.7 psi environment.  14.7 psi of fuming mad air molecules in hulk mode running head-first into the walls of a mere plastic coke bottle.   Why hasn't it burst open by now?


If air reaches the top of the dome and freezes, that means there is still a gas state up there, which means there's air pressure.  If the ice falls as snow, then more air is coming up to replace it.  If it freezes to the dome, and has been doing so for the last million or more years, how much ice is there by now?
Title: Re: Space Flight
Post by: Antonio on June 26, 2013, 01:26:57 AM
You "elaborated" a lot here. Now it's time to get back to reality. Please give some numerical answers to my previous questions, or admit that you don't know how to calculate the results, which is fine too.
In that case, give some results of real life experiments. You may then elaborate some theories.
Title: Re: Space Flight
Post by: Puttah on June 26, 2013, 01:51:47 AM
you have "compressed" the molecules even more, into a smaller space but in doing so, you have "robbed" the atmosphere outside of 85.3 psi.
wtf? I thought the atmosphere only had 14.7 psi to spare. I hope no one fills their tyres and steals all my oxygen  >:(

Seriously, your explanations are as simple minded as saying that as a train travelling at 50mph ploughs into a stationary car that was sitting on the tracks, since the car is now moving with the train at 50mph, it has robbed the train of 50mph...

I won't even bother with the rest of your post because it's probably also dumb crackpottery. You need to learn some actual science before you can even think you have the know-how to develop your own alternate theories.
Title: Re: Space Flight
Post by: mathsman on June 26, 2013, 02:29:39 AM

When you take 100 psi from the environment and cram it into a tyre, you immediately expand that tyre.
The reason the tyre expands is because you have "compressed" the molecules even more, into a smaller space but in doing so, you have "robbed" the atmosphere outside of 85.3 psi. The second you compress the molecules into the tyre, the air outside exerts more molecules onto the outside surface of the tire because it's replacing what you stole and has to equalise the pressure difference and it does so, by cramming into the tyre which creates and "equal" force against the outside rubber wall and the inside rubber wall, which is what you see as a stretch and the more air you put in, the more the outside molecules cram onto the outside wall until the tyre wall becomes too weak with stretching and explodes at it's weakest point.
I know you think that air pressure is no big deal because, after all..you can wave your arms about and do anything in this 14.7 psi environment so why is it so special.
The only way you will ever find out how special and powerful it is, is to go against it.
If you are still confused on this, I'll explain more if you are prepared to think clearly on it.

Atmospheric pressure at sea level in a given place is pretty constant. To change the pressure to any meaningful degree you would have to remove vast amounts of the atmosphere. The volume of air you are discussing here wouldn't make one iota of difference to the atmospheric pressure.

Atmospheric pressure on tyre before inflation: 1 atmosphere.
Atmospheric pressure on tyre after inflation : 1 atmosphere.
Title: Re: Space Flight
Post by: mathsman on June 26, 2013, 02:39:52 AM