It's 2015 and you aren't even close to owning a Spaceship

Quote from: Papa Legba on May 22, 2015, 01:26:32 PM

Whatever; when you have anything to add beyond personal abuse then get back to me...

Til then - buh-bye!!!

P.s. what do YOU think Hubbard, Parsons & Crowley were doing, INVOKING things?

Just for laughs, like...

no one gives a fuck what you think or what you have to say. just piss off already.

you are tedious. dull. frustrating. you are nothing except some sad pathetic idiot with nothing to do except type what you know is shit into a forum you care nothing about, and it's laughable due to how much time you've spent here. make you feel good, huh? typing out insults and wasting time for something you clearly care nothing about. must be the only place you can act tough. you have to be a real weakling in real life.

you do nothing except repeat yourself. people get bored of you, you find some new shit, then you repeat that. you're just a loser. so i really don't give a fuck what you're invoking or whatever it is that means you've decided to waste hours of your own time here. i have no desire to answer you, and no desire to stop insulting you, because this is precisely what you deserve.

you are a moron. a pathetic, sad little moron.

go fuck yourself.

Strangely enough, I agree with you.

You really are getting desperate.

Aren't you?

I'll get back to you later, once you've all sobered up...

There will be a test, so don't forget to study!

papa legba, you are a troll. end of. you are pathetic. just fuck off already, no one is interested in a word you have to say, and you dragging out this bs thread for so long is just excruciating. no one gives a fuck what you are to stay, you are just a sad litle individual. even as a troll, just repeating yourself for over a dozen pages is just the product of a sick little mind.
you are pathetic.

some of us actually care about advancing flat earth theory. you however are just a grade a buffooon. you are dull, tedious, utterly uninteresting, and moronic. it is not often i agree with round earthers, but on this case it is clear.

you are a troll. you are a waste of time and of aether (or air as the scientifically illiterate call it). just leave. come back when you're remotely able to engage your brain, or at least when you're somewhat interesting.

you're pathetic. end of.

You speak for yourself. I'm happy to hear the thoughts of anyone who is dealing with their indoctrination. And for God's sake, learn how to capitilize letters. Is it laziness or a lack of education? I can't decide. Either way it makes you look stupid.

Quote from: JRoweSkeptic on May 22, 2015, 01:14:28 PM

papa legba, you are a troll. end of. you are pathetic. just fuck off already, no one is interested in a word you have to say, and you dragging out this bs thread for so long is just excruciating. no one gives a fuck what you are to stay, you are just a sad litle individual. even as a troll, just repeating yourself for over a dozen pages is just the product of a sick little mind.
you are pathetic.

some of us actually care about advancing flat earth theory. you however are just a grade a buffooon. you are dull, tedious, utterly uninteresting, and moronic. it is not often i agree with round earthers, but on this case it is clear.

you are a troll. you are a waste of time and of aether (or air as the scientifically illiterate call it). just leave. come back when you're remotely able to engage your brain, or at least when you're somewhat interesting.

you're pathetic. end of.

You speak for yourself. I'm happy to hear the thoughts of anyone who is dealing with their indoctrination. And for God's sake, learn how to capitilize letters. Is it laziness or a lack of education? I can't decide. Either way it makes you look stupid.

Do you use the 12 step program in Indoctrinated Anonymous? 

No-one has really dealt with my question re. Hubbard, Parsons & Crowley all INVOKING stuff; you can't just wish it away, you know?

So; exactly WHAT were two proven CULT-LEADERS |(& Jack Parsons, lol!) doing when they all hung out together?

No-one has really dealt with my question re. Hubbard, Parsons & Crowley all INVOKING stuff; you can't just wish it away, you know?

So; exactly WHAT were two proven CULT-LEADERS |(& Jack Parsons, lol!) doing when they all hung out together?

Being zealots together. Who cares?

AHA!!!

SO; Jack Parsons, founder of JPL, was a 'zealot', yes?

NOW we're getting somewhere...

The OTHER TWO zealots he hung out with founded CULTS; what, precisely, did Jack Parsons found?

Getting the picture yet, space-cultists?

Quote from: legion on May 22, 2015, 01:47:53 PM

Quote from: JRoweSkeptic on May 22, 2015, 01:14:28 PM

papa legba, you are a troll. end of. you are pathetic. just fuck off already, no one is interested in a word you have to say, and you dragging out this bs thread for so long is just excruciating. no one gives a fuck what you are to stay, you are just a sad litle individual. even as a troll, just repeating yourself for over a dozen pages is just the product of a sick little mind.
you are pathetic.

some of us actually care about advancing flat earth theory. you however are just a grade a buffooon. you are dull, tedious, utterly uninteresting, and moronic. it is not often i agree with round earthers, but on this case it is clear.

you are a troll. you are a waste of time and of aether (or air as the scientifically illiterate call it). just leave. come back when you're remotely able to engage your brain, or at least when you're somewhat interesting.

you're pathetic. end of.

You speak for yourself. I'm happy to hear the thoughts of anyone who is dealing with their indoctrination. And for God's sake, learn how to capitilize letters. Is it laziness or a lack of education? I can't decide. Either way it makes you look stupid.

Do you use the 12 step program in Indoctrinated Anonymous?

I question everything, so therefore, I'm not indoctrinated. No steps required.

Everyone; you have made my night with your battiness; honestly, you are all hilarious.

Thank you.

When I return. I'd like to get back to my refutation of NASA's 'man on skateboard' false analogy, which none of you truly addressed.

We'll get there, eventually... You'll be cured, should you wish.

The door is always open.

Is there  any particular reason this PAPA LEGBA person has not yet been banned by the moderators for consistently breaking the forum's rules?

Low content in upper forum; obscenities; flaming; repeatedly off-topic; personal insults and ad hominems; inflammatory language etc.  Or is he/she one of the honoured few that the moderators encourage in order to inject a bit of controversy into the forums?

Quote from: legion on May 22, 2015, 11:52:30 AM

Quote from: markjo on May 21, 2015, 01:19:18 PM

Quote from: legion on May 21, 2015, 12:28:45 PM

Here's what my logic tells me:

All of the mass (gas/liquid) in the system will move toward the opening. Nothing will push opposite the opening. The pressure inside the vessel will be reduced at a constant rate until all of the mass has exited.

What direction is the pressure remaining in the vessel pushing while the pressure is being reduced?  Is all of the pressure directed only at the opening, or is it pushing against the chamber equally in all directions, including the opening?

Quote from: legion on May 21, 2015, 12:28:45 PM

No motion will occur as no external force has been applied, as per Newton's first law.

Again, I'm not worried about motion at this point.  I'm only concerned with the balance of action/reaction forces.

The pressure will be the same at all points. If you start with 500psi, then release 100psi, you will now have a vessel pressurised to 400psi. You could have pressure gauges all around the vessel and they would all read the same (while the pressure is being released as well).

Yes, the pressure would be equal all around the vessel, except for the one square inch hole.  Since there is nothing there to oppose the pressure within the vessel, the forces are unbalanced resulting in a net force on the surface opposite the opening.

It sounds like you have misunderstood Newton's third law. Let's call the mass inside the pressure vessel, body A.

I hope you are aware that that all that pressurised gas is a body, in itself, contained within the pressure vessel?

In order for Newton's third law to apply, body A must exert a force on another body, body B. We can now call the pressurised gas, body A, and the containing vessel, body B. The third law applies. The pressurised gas will apply a force to the vessel (which will be returned as long as it has been made correctly).  As the mass of body A is reduced, the force applied to body B (the pressure vessel), is also reduced. Further, as body B is the body that is reducing the force on itself (through the opening) and the system as a whole, a reaction force is cancelled out.

But here is the thing. Even if a force were generated (which it isn't), the force would be purely internal and no motion would result. Newton wrote his first law to make that explicit.

Quote from: Rayzor on May 21, 2015, 08:16:05 AM

I specifically said I didn't want to argue, because you seem to be very fixed in your opinion,    and very likely you'll not agree with anything I could say.   The point I was trying to establish is, what exactly is the basis of your understanding of why rockets don't work in space.

Free expansion is why they can't work in space. Free expansion is why they couldn't get too far up into the atmosphere, never mind what you believe space to be.

Quote from: Rayzor on May 21, 2015, 08:16:05 AM

We've established that the central issue is the view that there is nothing for the rocket to push against.    The laws of physics say that you don't need anything to push against.
If you disagree with the following, then just briefly say why and we leave it at that,   we don't need to drag this out into a protracted argument that ultimately ends in insults.

The laws of physics aren't laws when dealing with this. It's the laws of lies or guesswork.
The fact that a person can't envisage himself being in a vacuum and unable to distinguish it from being at sea level doing his stuff; it's bound to sway a person towards the bogus physics laws.

If you do not have any resistive force to your energy, then you simply do not move, whether that's a person or a rocket.
Here's an experiment for you to try.
Tie a strong box from a rafter and you and a friend get inside of it and shut the lid.
Let's call the box the inside of your rocket chamber and you and your friend are the fuel mix.
You are sat above your friend. He can smell your arse and the crease of your ball sack through your khaki shorts but this is irrelevant, as it's just an occupational hazard.
Ok so you tell him to push down onto the bottom of the box.
He does this and realises that to break it he has to lever off of your arse whilst you have to lever your shoulders and head against the top of the box lid.
Let's assume that your box lid is solid and won't break.

Now your friend manages to break through his lid due to him squashing you. All you are doing is being jammed against your lid until he breaks his lid and falls out under the pressure he and you used as force.
He shoots out and hits the deck. Where are you?
You don't hit the ceiling do you? you drop out behind him like a limp dick because you both expended your energy pushing each otehr to break his lid and now you are left in the box for a sec after your friend smashes his face off the floor. Then you follow like a newly hatched chick falling from a nest onto your mate.

Quote from: Rayzor on May 21, 2015, 08:16:05 AM

Imagine  a cube shaped sealed metal box floating in the vacuum of space  1m x 1m x 1m  and we have pressurized the box with air to 10 kg per square meter   
The area of  each of the sides of the cube is 1 square meter so there is  10 kg  pressing  from the inside on each side of the cube.   Now we cut a  0.1 square meter hole in the bottom of the cube,  so the bottom now has only 9kg  pressing on it,  but the top still has 10kg  so there is 1kg force difference between the top and bottom,  pushing the box upwards.   And the box moves up.  It doesn't need to push against anything.

I'll leave the equations for another day.

You lost your force when you cut the cube open. You lost it to free expansion.
Try and make things easier for yourself or you will get frustrated.

I don't know about anyone else, but if my physics text book had used words like "Arse" and "Ball Sack," I would have enjoyed the class a lot more!

It sounds like you have misunderstood Newton's third law.

Well, it's fairly obvious that at least one of us has and I don't think that it's me. 

Let's call the mass inside the pressure vessel, body A.

I hope you are aware that that all that pressurised gas is a body, in itself, contained within the pressure vessel?

Agreed.

In order for Newton's third law to apply, body A must exert a force on another body, body B. We can now call the pressurised gas, body A, and the containing vessel, body B. The third law applies. The pressurised gas will apply a force to the vessel (which will be returned as long as it has been made correctly).

As the mass of body A is reduced, the force applied to body B (the pressure vessel), is also reduced.

So far, so good.

Further, as body B is the body that is reducing the force on itself (through the opening) and the system as a whole, a reaction force is cancelled out.

Here is where we disagree.  Let's say that the vessel (body B) is a box with each side being 10 in² and the the gas (body A) is 500 psi.  This means that each side has a force of 5000 pounds being applied.  Newton's third law says that each side of the the vessel will push back with 5000 pounds of force and the system will be in equilibrium.  Are we agreed so far?

Okay, now let's cut a one square inch hole in one side.  Now we have a box with 5 sides that have an area of 10 square inches and one side with an area of 9 square inches.  This means that (at least for an instant) the side with the hole in it has 5000 pounds of force being applied by the gas, but can only push back with 4500 pounds of force and the system is no longer in equilibrium.  Are we still agreed?

But here is the thing. Even if a force were generated (which it isn't), the force would be purely internal and no motion would result. Newton wrote his first law to make that explicit.

Actually, Newton's first law (inertia) specifically refers to bodies at rest or in uniform motion.  In other words, in a state of equilibrium.  A vessel under pressure with a hole in one end is most certainly not in a state of equilibrium.

Good vid scepti. The onlything that could be said of the demonstration is, the paper blocking the nozzle provides backward pressure cancleing the movement. I think if you put your hand near the nozzle as it is going, the car would go faster. IfI have time I will try it. That way it would show the pressurein back of the car was moving it, not just the air leaving the nozzle.

This guy has a kickstarter project to fund the experiment.

https://www.kickstarter.com/projects/62683336/propulsion-in-vacuum-experiment-to-debunk-prove-sp

Mind you I think NASA has a bigger budget,  bigger rockets and have proved it  beyond any reasonable doubt  many times already,  but  why not.

Speaking of rockets I came across an interesting documentary on the failed Russian N1 rocket project.   
It was far more successful than it was originally thought in the west,  Russian rocket engineering is still, even today years ahead of the technology of the USA. 

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I don't know about anyone else, but if my physics text book had used words like "Arse" and "Ball Sack," I would have enjoyed the class a lot more!

And to top it all I was being polite and reasonable when he came back with that incomprehensible verbal barrage.   I think it's just symptomatic of his mental condition.

Everyone; you have made my night with your battiness; honestly, you are all hilarious.

Thank you.

When I return. I'd like to get back to my refutation of NASA's 'man on skateboard' false analogy, which none of you truly addressed.

We'll get there, eventually... You'll be cured, should you wish.

The door is always open.

They are getting irritated because you're speaking the truth. They are desperately trying not to answer your last question because they know it leads to the little fantasy gathering of those employed to take away naive people's thoughts and gather them into cult groups.
It's no more than Werner Von Braun and Walt Disney, plus Arthur C Clarke , etc, have done over the years. Made people go all gooey eyed over space exploits and made them as believable as disney cartoons are for pre-school kids.

Let's face it, kids can go and meet astronauts at little space conventions just as asily as they can go and meet disney characters at disneyland.
All characters are made by the same kind of people. All fantasy.

When a kid can run up to a character inside a Mickey mouse suit and cuddle that character, not knowing what or who the hell is inside that suit and yet believing that it is actually Mickey mouse; it's no wonder how easly kids and even grown up's can be brainwashed into it all.

It's a simple play on our naive brains. We are all guilty of believing in fantasy as a truth on many occasions in life but it's about seeing past it and actually deciphering what is potentially real and what is plainly bullshit.

Is there  any particular reason this PAPA LEGBA person has not yet been banned by the moderators for consistently breaking the forum's rules?

Low content in upper forum; obscenities; flaming; repeatedly off-topic; personal insults and ad hominems; inflammatory language etc.  Or is he/she one of the honoured few that the moderators encourage in order to inject a bit of controversy into the forums?

If he gets banned they better ban every free thinker and just leave you bastards to duke it out with the remainihng flat Earther's who stay.
You people are like parasites. You use names for whatever topics as if you're duping people. How silly.

The fact that you people beg for bans is enough for anyone to see just what your game is. Shut down the forum or make it redundant because you see that too many people are waking up and getting a little bit close to the bone.

Here is where we disagree.  Let's say that the vessel (body B) is a box with each side being 10 in² and the the gas (body A) is 500 psi.  This means that each side has a force of 5000 pounds being applied.  Newton's third law says that each side of the the vessel will push back with 5000 pounds of force and the system will be in equilibrium.  Are we agreed so far?

Okay, now let's cut a one square inch hole in one side.  Now we have a box with 5 sides that have an area of 10 square inches and one side with an area of 9 square inches.  This means that (at least for an instant) the side with the hole in it has 5000 pounds of force being applied by the gas, but can only push back with 4500 pounds of force and the system is no longer in equilibrium.  Are we still agreed?

Yes, this is where we disagree. In your example, the side with the 1" opening no longer has 5000psi of force being applied to it. Nor does the side opposite it (or any other side). It doesn't matter whether the pressure is reduced gradually or instantaneosly. The pressure is released and reduced simultaneously. Therefore, there is no net force as the system remains balanced.

Quote from: markjo on May 22, 2015, 05:29:17 PM

Here is where we disagree.  Let's say that the vessel (body B) is a box with each side being 10 in² and the the gas (body A) is 500 psi.  This means that each side has a force of 5000 pounds being applied.  Newton's third law says that each side of the the vessel will push back with 5000 pounds of force and the system will be in equilibrium.  Are we agreed so far?

Okay, now let's cut a one square inch hole in one side.  Now we have a box with 5 sides that have an area of 10 square inches and one side with an area of 9 square inches.  This means that (at least for an instant) the side with the hole in it has 5000 pounds of force being applied by the gas, but can only push back with 4500 pounds of force and the system is no longer in equilibrium.  Are we still agreed?

Yes, this is where we disagree. In your example, the side with the 1" opening no longer has 5000psi of force being applied to it. Nor does the side opposite it (or any other side). It doesn't matter whether the pressure is reduced gradually or instantaneosly. The pressure is released and reduced simultaneously. Therefore, there is no net force as the system remains balanced.

The instant that the hole is opened there will be an imbalance and that force will cause the box to accelerate,  the imbalance ( and that force ) will continue for the time it takes for the gas to exhaust itself through the hole.   
The force ( thrust ) will start at 500 pounds  ( 5000-4500)  and drop to zero some time after the hole is opened.   The pressure doesn't drop to zero instantaneously, the time is dependant on the initial pressure, the size of the hole and the volume of the box.

Quote from: legion on May 23, 2015, 01:06:03 AM

Quote from: markjo on May 22, 2015, 05:29:17 PM

Here is where we disagree.  Let's say that the vessel (body B) is a box with each side being 10 in² and the the gas (body A) is 500 psi.  This means that each side has a force of 5000 pounds being applied.  Newton's third law says that each side of the the vessel will push back with 5000 pounds of force and the system will be in equilibrium.  Are we agreed so far?

Okay, now let's cut a one square inch hole in one side.  Now we have a box with 5 sides that have an area of 10 square inches and one side with an area of 9 square inches.  This means that (at least for an instant) the side with the hole in it has 5000 pounds of force being applied by the gas, but can only push back with 4500 pounds of force and the system is no longer in equilibrium.  Are we still agreed?

Yes, this is where we disagree. In your example, the side with the 1" opening no longer has 5000psi of force being applied to it. Nor does the side opposite it (or any other side). It doesn't matter whether the pressure is reduced gradually or instantaneosly. The pressure is released and reduced simultaneously. Therefore, there is no net force as the system remains balanced.

The instant that the hole is opened there will be an imbalance and that force will cause the box to accelerate,  the imbalance ( and that force ) will continue for the time it takes for the gas to exhaust itself through the hole.   
The force ( thrust ) will start at 500 pounds  ( 5000-4500)  and drop to zero some time after the hole is opened.   The pressure doesn't drop to zero instantaneously, the time is dependant on the initial pressure, the size of the hole and the volume of the box.

I maintain there will be no imbalance. Pressure is released, pressure is reduced. A simple demonstration of this principle is as follows:

1. Blow up a long party balloon.
2. Release the air from the balloon at different speeds.
3. Observe what happens.

Here is what I observe: as the pressure is reduced inside the balloon, the far end contracts back towards the middle (because it's not under as much pressure). According to your logic, I should observe a force pushing on the closed end of the balloon in the opposite direction to the air escaping from the balloon. Effectively, the balloon should be stretched when deflated. But it isn't.

This should settle the matter to any reasonable person.

Quote from: Rayzor on May 23, 2015, 03:20:31 AM

Quote from: legion on May 23, 2015, 01:06:03 AM

Quote from: markjo on May 22, 2015, 05:29:17 PM

Here is where we disagree.  Let's say that the vessel (body B) is a box with each side being 10 in² and the the gas (body A) is 500 psi.  This means that each side has a force of 5000 pounds being applied.  Newton's third law says that each side of the the vessel will push back with 5000 pounds of force and the system will be in equilibrium.  Are we agreed so far?

Okay, now let's cut a one square inch hole in one side.  Now we have a box with 5 sides that have an area of 10 square inches and one side with an area of 9 square inches.  This means that (at least for an instant) the side with the hole in it has 5000 pounds of force being applied by the gas, but can only push back with 4500 pounds of force and the system is no longer in equilibrium.  Are we still agreed?

Yes, this is where we disagree. In your example, the side with the 1" opening no longer has 5000psi of force being applied to it. Nor does the side opposite it (or any other side). It doesn't matter whether the pressure is reduced gradually or instantaneosly. The pressure is released and reduced simultaneously. Therefore, there is no net force as the system remains balanced.

The instant that the hole is opened there will be an imbalance and that force will cause the box to accelerate,  the imbalance ( and that force ) will continue for the time it takes for the gas to exhaust itself through the hole.   
The force ( thrust ) will start at 500 pounds  ( 5000-4500)  and drop to zero some time after the hole is opened.   The pressure doesn't drop to zero instantaneously, the time is dependant on the initial pressure, the size of the hole and the volume of the box.

I maintain there will be no imbalance. Pressure is released, pressure is reduced. A simple demonstration of this principle is as follows:

1. Blow up a long party balloon.
2. Release the air from the balloon at different speeds.
3. Observe what happens.

Here is what I observe: as the pressure is reduced inside the balloon, the far end contracts back towards the middle (because it's not under as much pressure). According to your logic, I should observe a force pushing on the closed end of the balloon in the opposite direction to the air escaping from the balloon. Effectively, the balloon should be stretched when deflated. But it isn't.

This should settle the matter to any reasonable person.

1. Blow up a party balloon.
2. Let go of the balloon  ( releasing the pressurized air inside )
3. Observe the balloon take off around the room,  the time it whizzes around for depends on the time it takes for the air to escape.

Why does the balloon move?  And why would it be any different in a vacuum.   
The flow rate of air through the neck of the balloon is proportional to the pressure difference between the inside and outside of the balloon,  and the size of the flow restriction  ( the neck )  or on a rocket it would be the nozzle.   In a vacuum the outside pressure is zero.  So the flow rate will be higher in a vacuum,  but not instantaneous.   The air velocity through the restriction is described by Bernoulli's equation  if the gas velocity is higher the pressure is lower,  like a venturi.

Rocket engines are designed to maximize the combustion chamber pressures. Higher pressure equals more thrust.

Quote from: legion on May 23, 2015, 04:07:10 AM

Quote from: Rayzor on May 23, 2015, 03:20:31 AM

Quote from: legion on May 23, 2015, 01:06:03 AM

Quote from: markjo on May 22, 2015, 05:29:17 PM

Here is where we disagree.  Let's say that the vessel (body B) is a box with each side being 10 in² and the the gas (body A) is 500 psi.  This means that each side has a force of 5000 pounds being applied.  Newton's third law says that each side of the the vessel will push back with 5000 pounds of force and the system will be in equilibrium.  Are we agreed so far?

Okay, now let's cut a one square inch hole in one side.  Now we have a box with 5 sides that have an area of 10 square inches and one side with an area of 9 square inches.  This means that (at least for an instant) the side with the hole in it has 5000 pounds of force being applied by the gas, but can only push back with 4500 pounds of force and the system is no longer in equilibrium.  Are we still agreed?

Yes, this is where we disagree. In your example, the side with the 1" opening no longer has 5000psi of force being applied to it. Nor does the side opposite it (or any other side). It doesn't matter whether the pressure is reduced gradually or instantaneosly. The pressure is released and reduced simultaneously. Therefore, there is no net force as the system remains balanced.

The instant that the hole is opened there will be an imbalance and that force will cause the box to accelerate,  the imbalance ( and that force ) will continue for the time it takes for the gas to exhaust itself through the hole.   
The force ( thrust ) will start at 500 pounds  ( 5000-4500)  and drop to zero some time after the hole is opened.   The pressure doesn't drop to zero instantaneously, the time is dependant on the initial pressure, the size of the hole and the volume of the box.

I maintain there will be no imbalance. Pressure is released, pressure is reduced. A simple demonstration of this principle is as follows:

1. Blow up a long party balloon.
2. Release the air from the balloon at different speeds.
3. Observe what happens.

Here is what I observe: as the pressure is reduced inside the balloon, the far end contracts back towards the middle (because it's not under as much pressure). According to your logic, I should observe a force pushing on the closed end of the balloon in the opposite direction to the air escaping from the balloon. Effectively, the balloon should be stretched when deflated. But it isn't.

This should settle the matter to any reasonable person.

1. Blow up a party balloon.
2. Let go of the balloon  ( releasing the pressurized air inside )
3. Observe the balloon take off around the room,  the time it whizzes around for depends on the time it takes for the air to escape.

Why does the balloon move?  And why would it be any different in a vacuum.   
The flow rate of air through the neck of the balloon is proportional to the pressure difference between the inside and outside of the balloon,  and the size of the flow restriction  ( the neck )  or on a rocket it would be the nozzle.   In a vacuum the outside pressure is zero.  So the flow rate will be higher in a vacuum,  but not instantaneous.   The air velocity through the restriction is described by Bernoulli's equation  if the gas velocity is higher the pressure is lower,  like a venturi.

Rocket engines are designed to maximize the combustion chamber pressures. Higher pressure equals more thrust.

I'm not talking about the balloon flying around the room. I'm talking about observing what happens only to the balloon, whilst the pressure is reduced. I've added that to step 2 as I hadn't explicitly written that.

1. Blow up a long party balloon.
2. Release the air from the balloon at different speeds, whilst holding the balloon.
3. Observe what happens.

Here is what I observe: as the pressure is reduced inside the balloon, the far end contracts back towards the middle (because it's not under as much pressure). According to your logic, I should observe a force pushing on the closed end of the balloon in the opposite direction to the air escaping from the balloon. According to nasa, the balloon should be stretched when deflated. But it isn't.



The above image is what markjo and yourself claim is happening. That can be disproven in five minutes. All of the air moves to the opening. There is no " opposite direction reaction" inside the balloon. The only reaction is the balloon contracts at the rate the air is released.

But legion, your scenario fails because rocket ships don't have large hands holding them.  Therefore, Rayzor's scenario fits better.

But legion, your scenario fails because rocket ships don't have large hands holding them.  Therefore, Rayzor's scenario fits better.

I must admit,  hanging on to the balloon and then observing that it didn't move, was an option that never occurred to me.   

Quote from: BJ1234 on May 23, 2015, 04:56:25 AM

But legion, your scenario fails because rocket ships don't have large hands holding them.  Therefore, Rayzor's scenario fits better.

I must admit,  hanging on to the balloon and then observing that it didn't move, was an option that never occurred to me.

I'm not particularly smart, but if I hold the balloon's neck and let the air out, wouldn't the force of the exhaust be on my hand?   

Quote from: BJ1234 on May 23, 2015, 04:56:25 AM

But legion, your scenario fails because rocket ships don't have large hands holding them.  Therefore, Rayzor's scenario fits better.

I must admit,  hanging on to the balloon and then observing that it didn't move, was an option that never occurred to me.

You're missing the point. Deliberately I assume.



Does the action (air coming out) give a reaction opposite, as per the above image?

Quote from: Rayzor on May 23, 2015, 05:25:50 AM

Quote from: BJ1234 on May 23, 2015, 04:56:25 AM

But legion, your scenario fails because rocket ships don't have large hands holding them.  Therefore, Rayzor's scenario fits better.

I must admit,  hanging on to the balloon and then observing that it didn't move, was an option that never occurred to me.

You're missing the point. Deliberately I assume.



Does the action (air coming out) give a reaction opposite, as per the above image?

Yes, there is, but it's being countered by the external force of your hand holding onto the balloon.

Quote from: legion on May 23, 2015, 05:51:30 AM

Quote from: Rayzor on May 23, 2015, 05:25:50 AM

Quote from: BJ1234 on May 23, 2015, 04:56:25 AM

But legion, your scenario fails because rocket ships don't have large hands holding them.  Therefore, Rayzor's scenario fits better.

I must admit,  hanging on to the balloon and then observing that it didn't move, was an option that never occurred to me.

You're missing the point. Deliberately I assume.



Does the action (air coming out) give a reaction opposite, as per the above image?

Yes, there is, but it's being countered by the external force of your hand holding onto the balloon.

A hand holding the balloon is irrelevant.

The concept that nasa rely on is that a force going one way, gives a reaction force going the other way. We are told (and shown) that the reaction force is on the opposite end of the balloon.

Therefore, in my experiment the held balloon should protrude at the unopened end while air is escaping. That is, unless you can explain another means by which the "reaction" force is applied?

A hand holding the balloon is irrelevant.

Why?

Therefore, in my experiment the held balloon should protrude at the unopened end while air is escaping.

Why? Not only should the balloon resist such an action (another action/reaction to take into account), not only is the interior of the balloon not perfectly still (so there will be no direct line through), but this is real life, not a smoothed-out diagram.