.....

Quote from: Kendrick on November 30, 2012, 09:16:09 AM

Quote from: sceptimatic on November 30, 2012, 09:08:05 AM

There is no low pressure in space. There is no pressure at all.

Ok - let me make a slight change in the wording of my explaination to make it more clear:

Quote

In this scenario - the gasses inside the 'rocket' - or any container filled with a gas under pressure - will create propulsion as they move from the high pressure through the 'breach' and expand in the zero pressure environment on the other side.

So what are these expanding gases pushing against?

The rocket's combustion chamber.

So what are these expanding gases pushing against?

In this scenario as the gas leaves the high pressure environment into the zero pressure environment it expands in all directions - pressing against the sides of breach and the outside of the container - creating force and propulsion.

So it comes out and somehow turns around, gripping the sides and pushing the rocket?
So for it to push this rocket it must use leverage...what leverage is it using?

Nope -

The gas escapes the breach and expands to attempt to fill the vacuum - this expansion creates force against the breach.

Quote from: Kendrick on November 30, 2012, 09:42:53 AM

Quote from: sceptimatic on November 30, 2012, 09:38:57 AM

So it comes out and somehow turns around, gripping the sides and pushing the rocket?
So for it to push this rocket it must use leverage...what leverage is it using?

Nope -

The gas escapes the breach and expands to attempt to fill the vacuum - this expansion creates force against the breach.

How does it create force in the vacuum?

The gas escapes the breach and expands to attempt to fill the vacuum - this expansion creates force against the breach.

Quote from: Kendrick on November 30, 2012, 09:35:28 AM

Quote from: sceptimatic on November 30, 2012, 09:25:52 AM

So what are these expanding gases pushing against?

In this scenario as the gas leaves the high pressure environment into the zero pressure environment it expands in all directions - pressing against the sides of breach and the outside of the container - creating force and propulsion.

So it comes out and somehow turns around, gripping the sides and pushing the rocket?

So for it to push this rocket it must use leverage...what leverage is it using?

What are you talking about "leverage"? no matter how many times you change your question, the answer is always going to be the same. the fact is all forces equalize, and therefore if there is a force in one direction there is a reaction somewhere else. if you were to have a bomb in space the energy of the explosion would expell in all dircections. if you have it so that there is a solid container*, unless the container splits apart and explodes then it has to conform to a certain direction to equalize the force, so if you burn fuel, the fuel tries to expand in all directions causing it partially to try to push the container apart, but because it is funneled and the container does not come apart it conforms to one single direction exactly opposite the direction of force.


* [edit] open at one end.

Quote from: Kendrick on November 30, 2012, 09:45:28 AM

Quote from: sceptimatic on November 30, 2012, 09:44:11 AM

Quote from: Kendrick on November 30, 2012, 09:42:53 AM

Quote from: sceptimatic on November 30, 2012, 09:38:57 AM

So it comes out and somehow turns around, gripping the sides and pushing the rocket?
So for it to push this rocket it must use leverage...what leverage is it using?

Nope -

The gas escapes the breach and expands to attempt to fill the vacuum - this expansion creates force against the breach.

How does it create force in the vacuum?

The gas escapes the breach and expands to attempt to fill the vacuum - this expansion creates force against the breach.

Ok, it's expanding and attempting to fill the vacuum but it's failing to "fill" the vacuum, so where is it getting it's force from?

from the burning fuel.

Quote from: Kendrick on November 30, 2012, 09:45:28 AM

Quote from: sceptimatic on November 30, 2012, 09:44:11 AM

Quote from: Kendrick on November 30, 2012, 09:42:53 AM

Quote from: sceptimatic on November 30, 2012, 09:38:57 AM

So it comes out and somehow turns around, gripping the sides and pushing the rocket?
So for it to push this rocket it must use leverage...what leverage is it using?

Nope -

The gas escapes the breach and expands to attempt to fill the vacuum - this expansion creates force against the breach.

How does it create force in the vacuum?

The gas escapes the breach and expands to attempt to fill the vacuum - this expansion creates force against the breach.

Ok, it's expanding and attempting to fill the vacuum but it's failing to "fill" the vacuum, so where is it getting it's force from?

There is a combustion chamber in which the fuel is burning at such a high rate that it is essentially a continuous explosion. There is an opening at one end of the combustion chamber. When the fuel burns, it expands in all directions, pushing on all sides of the chamber. Since there is an opening on one side, it escapes out that side, the stuff that is still pushing within the chamber forces the rocket forwards in the opposite direction that the nozzle is facing.

The explosion itself its already creating force to create expansion. The force making the rocket move is that expansion against the rocket, mass causing pressure against mass.
The rocket moves because of the expansion of gasses against the rocket, not against the vacuum.

The point is where the explosion would be. Is not an accurate representation of a rocket, just to show the forces.

Ok, it's expanding and attempting to fill the vacuum but it's failing to "fill" the vacuum, so where is it getting it's force from?

As long as the pressure on one side of the 'breach' is lower - the expanding gasses will create force on the 'breach.'

I 'think' as the pressures on both sides of the breach approach equality the force of the gasses expanding will diminish, someone more versed then I may need to correct or clarify.

The point is - that the difference in pressure in a vacuum will lead to more propulsion via the expanding of gasses against the 'breach' then the pressure at sea-level.

Quote from: Mantaxi on November 30, 2012, 09:50:08 AM

Quote from: sceptimatic on November 30, 2012, 09:46:42 AM

Quote from: Kendrick on November 30, 2012, 09:45:28 AM

Quote from: sceptimatic on November 30, 2012, 09:44:11 AM

Quote from: Kendrick on November 30, 2012, 09:42:53 AM

Quote from: sceptimatic on November 30, 2012, 09:38:57 AM

So it comes out and somehow turns around, gripping the sides and pushing the rocket?
So for it to push this rocket it must use leverage...what leverage is it using?

Nope -

The gas escapes the breach and expands to attempt to fill the vacuum - this expansion creates force against the breach.

How does it create force in the vacuum?

The gas escapes the breach and expands to attempt to fill the vacuum - this expansion creates force against the breach.

Ok, it's expanding and attempting to fill the vacuum but it's failing to "fill" the vacuum, so where is it getting it's force from?

from the burning fuel.

Do you think the vacuum of space cares what burning fuel is?
The vacuum of space will treat burning fuel in exactly the same way as non burning. It will simply accept it into it's vastness as fast as it is thrown at it.

Result:
No moving rocket.

Is not the gases against vacuum the ones causing the movement, is the gasses pressing against the rocket that cause the rocket to move. If you push something it will move, if gasses at high pressure pushes a rocket it will move.

Quote from: Mantaxi on November 30, 2012, 09:48:49 AM

Quote from: sceptimatic on November 30, 2012, 09:38:57 AM

Quote from: Kendrick on November 30, 2012, 09:35:28 AM

Quote from: sceptimatic on November 30, 2012, 09:25:52 AM

So what are these expanding gases pushing against?

In this scenario as the gas leaves the high pressure environment into the zero pressure environment it expands in all directions - pressing against the sides of breach and the outside of the container - creating force and propulsion.

So it comes out and somehow turns around, gripping the sides and pushing the rocket?

So for it to push this rocket it must use leverage...what leverage is it using?

What are you talking about "leverage"? no matter how many times you change your question, the answer is always going to be the same. the fact is all forces equalize, and therefore if there is a force in one direction there is a reaction somewhere else. if you were to have a bomb in space the energy of the explosion would expell in all dircections. if you have it so that there is a solid container, unless the container splits apart and explodes then it has to conform to a certain direction to equalize the force, so if you burn fuel, the fuel tries to expand in all directions causing it partially to try to push the container apart, but because it is funneled and the container does not come apart it conforms to one single direction exactly opposite the direction of force.

And what is opposite the direction of force?

A vacuum that immediately nullifies that force, rendering the rocket useless as it's force is being took away from it as fast as it is getting expended.

Are you really that clueless, sorry; it seems like you are delibrately missing the point.

Imagine a bomb in space, that has a coating of shrapnel, when it explodes because of a comination of some kind of fuel and fire, the shrapnel will go everywhere. now imagine you have a a bomib in space inside an indestuctable container with one end open, when the bomb explodes it will push all the container's edges, but because it is indestructable, the container will move uniformly in a direction that is an average distribution of the energy propelled into it. now imagine that the bomb is continuous bomb attached to the the inside of the container, this will cause movement. very simplistic explanation, but it should make you realize the mechanism.

Quote from: robertotrevor on November 30, 2012, 09:51:55 AM

The explosion itself its already creating force to create expansion. The force making the rocket move is that expansion against the rocket, mass causing pressure against mass.
The rocket moves because of the expansion of gasses against the rocket, not against the vacuum.

The point is where the explosion would be. Is not an accurate representation of a rocket, just to show the forces.

This is exactly you saying that the rocket pushes against itself with the exhaust having no part in it.
It's so silly , it's actually scary to think people believe this.

You don't get it, the exhaust against vacuum does nothing, but there are also gases moving against the rocket. The gasses push the rocket so it moves, is not the rocket against the rocket because this gases are not attached to the rocket and are constantly leaving it.

Quote from: robertotrevor on November 30, 2012, 09:51:55 AM

The explosion itself its already creating force to create expansion. The force making the rocket move is that expansion against the rocket, mass causing pressure against mass.
The rocket moves because of the expansion of gasses against the rocket, not against the vacuum.

The point is where the explosion would be. Is not an accurate representation of a rocket, just to show the forces.

This is exactly you saying that the rocket pushes against itself with the exhaust having no part in it.
It's so silly , it's actually scary to think people believe this.

what is more scary is that you think something needs to push against air to move.

I 'think' as the pressures on both sides of the breach approach equality the force of the gasses expanding will diminish, someone more versed then I may need to correct or clarify.

I think I know what you mean. For example, if we were talking about a simple can of air in space. If the can were breached, then the air would be propelled out, pushing the can in the opposite direction. As the air pressure in the can drops, there is less force pushing it, so it would diminish, you are correct. In the case of liquid fueled rockets, they have throttle controls, so the "pressure," or force, can be manually raised and lowered. It can fire full force until it's out of fuel if the pilot/person at the controls so desires.

Quote from: robertotrevor on November 30, 2012, 09:55:48 AM

Quote from: sceptimatic on November 30, 2012, 09:53:29 AM

Quote from: Mantaxi on November 30, 2012, 09:50:08 AM

Quote from: sceptimatic on November 30, 2012, 09:46:42 AM

Quote from: Kendrick on November 30, 2012, 09:45:28 AM

Quote from: sceptimatic on November 30, 2012, 09:44:11 AM

Quote from: Kendrick on November 30, 2012, 09:42:53 AM

Quote from: sceptimatic on November 30, 2012, 09:38:57 AM

So it comes out and somehow turns around, gripping the sides and pushing the rocket?
So for it to push this rocket it must use leverage...what leverage is it using?

Nope -

The gas escapes the breach and expands to attempt to fill the vacuum - this expansion creates force against the breach.

How does it create force in the vacuum?

The gas escapes the breach and expands to attempt to fill the vacuum - this expansion creates force against the breach.

Ok, it's expanding and attempting to fill the vacuum but it's failing to "fill" the vacuum, so where is it getting it's force from?

from the burning fuel.

Do you think the vacuum of space cares what burning fuel is?
The vacuum of space will treat burning fuel in exactly the same way as non burning. It will simply accept it into it's vastness as fast as it is thrown at it.

Result:
No moving rocket.

Is not the gases against vacuum the ones causing the movement, is the gasses pressing against the rocket that cause the rocket to move. If you push something it will move, if gasses at high pressure pushes a rocket it will move.

You cannot push your own rocket with your own gases, unless it is acting on an external force, which on Earth would be the "expansion" of the gases against the atmosphere.

Think of a "hot air balloon"

The burner heats up the air inside the balloon which forces the cold air out as heat rises, forcing the balloon upwards.

A rocket is a heavy opposite in that, the hot air is at the nozzle so is overcoming the cold air atmosphere all the time at force, which propels the rocket.

The science you are relying on is BS .

the science we are relying on is not understood by you; you have given no rational reason why can't understand it, and given no rational reason why it s flawed, and so your accusation that it is BS, seems to me, a shaming tactic designed to take the pressure off of you being too dumb to understand it.

The pressures on both sides cannot create equality because there is no pressure whatsoever in the vacuum of space to do that, so all you have is pressure coming from the rocket and the minute it leaves the rocket, it is swallowed up by space.

Space is neither hot or cold, so it has no preference what it's swallowing up.

Sorry - i think I may have confused you by providing too much detail.

You are in error in thinking that the vacuum 'swallows up' expanding gasses eliminating force from the equation.

The gases cannot just push the rocket without an external force to act against.

This assumption is wrong
The force is created by the fuel and fire which explodes creating particles in space, and the particles momentum collides with the container causing a transfer of energy.

On Earth it has that. It's called atmosphere.
In space, it's rendered a simply empty tin can.

No forces do not push against the atmosphere, in fact the atmosphere makes rockets inefficient, you are looking at reality the wrong way round.

Quote from: robertotrevor on November 30, 2012, 10:00:29 AM

Quote from: sceptimatic on November 30, 2012, 09:57:32 AM

Quote from: robertotrevor on November 30, 2012, 09:51:55 AM

The explosion itself its already creating force to create expansion. The force making the rocket move is that expansion against the rocket, mass causing pressure against mass.
The rocket moves because of the expansion of gasses against the rocket, not against the vacuum.

The point is where the explosion would be. Is not an accurate representation of a rocket, just to show the forces.

This is exactly you saying that the rocket pushes against itself with the exhaust having no part in it.
It's so silly , it's actually scary to think people believe this.

You don't get it, the exhaust against vacuum does nothing, but there are also gases moving against the rocket. The gasses push the rocket so it moves, is not the rocket against the rocket because this gases are not attached to the rocket and are constantly leaving it.

Have a word will you.

The gases cannot just push the rocket without an external force to act against.
On Earth it has that. It's called atmosphere.
In space, it's rendered a simply empty tin can.

Why don't you push against the atmosphere and see how far you get?

Quote from: sceptimatic on November 30, 2012, 10:09:10 AM

Quote from: robertotrevor on November 30, 2012, 10:00:29 AM

Quote from: sceptimatic on November 30, 2012, 09:57:32 AM

Quote from: robertotrevor on November 30, 2012, 09:51:55 AM

The explosion itself its already creating force to create expansion. The force making the rocket move is that expansion against the rocket, mass causing pressure against mass.
The rocket moves because of the expansion of gasses against the rocket, not against the vacuum.

The point is where the explosion would be. Is not an accurate representation of a rocket, just to show the forces.

This is exactly you saying that the rocket pushes against itself with the exhaust having no part in it.
It's so silly , it's actually scary to think people believe this.

You don't get it, the exhaust against vacuum does nothing, but there are also gases moving against the rocket. The gasses push the rocket so it moves, is not the rocket against the rocket because this gases are not attached to the rocket and are constantly leaving it.

Have a word will you.

The gases cannot just push the rocket without an external force to act against.
On Earth it has that. It's called atmosphere.
In space, it's rendered a simply empty tin can.

Why don't you push against the atmosphere and see how far you get?

seconded.

Quote from: Kendrick on November 30, 2012, 10:10:26 AM

Quote from: sceptimatic on November 30, 2012, 10:00:19 AM

The pressures on both sides cannot create equality because there is no pressure whatsoever in the vacuum of space to do that, so all you have is pressure coming from the rocket and the minute it leaves the rocket, it is swallowed up by space.

Space is neither hot or cold, so it has no preference what it's swallowing up.

Sorry - i think I may have confused you by providing too much detail.

You are in error in thinking that the vacuum 'swallows up' expanding gasses eliminating force from the equation.

I'm not in error. You are in error because you are relying on what you have been brainwashed to rely on and are sticking to it like glue, which is fine by me as I won;t be pushed off course by any pressure acting upon me, like your fake working space rockets.

If you want to prove anything to me, you better do a hell of a lot better or just accept you are wrong and have been fooled.

Ok explain to us the alternative, which is consistent,  more comprehensive than the origincal explaination and which  is also easily falsifiable.

If you cannot do this I have no reason to question the already much more corroborated theory.

I'm not in error. You are in error because you are relying on what you have been brainwashed to rely on and are sticking to it like glue, which is fine by me as I won;t be pushed off course by any pressure acting upon me, like your fake working space rockets.

If you want to prove anything to me, you better do a hell of a lot better or just accept you are wrong and have been fooled.

I believe I am laboring under the incorrect assumption that you wish to be enlightened - it appears you are merely posting inflammatory statements to attempt to elicit emotional responses for your amusement. 

Correct me if i'm wrong, but you seem more interested in calling us brainwashed then making an attempt to experiment or understand the points we are trying to convey.

Quote from: Mantaxi on November 30, 2012, 10:12:53 AM

Quote from: sceptimatic on November 30, 2012, 10:09:10 AM

The gases cannot just push the rocket without an external force to act against.

This assumption is wrong
The force is created by the fuel and fire which explodes creating particles in space, and the particles momentum collides with the container causing a transfer of energy.

Quote

Please tell me you haven't stooped to this level.

Quote from: sceptimatic on November 30, 2012, 10:09:10 AM

On Earth it has that. It's called atmosphere.
In space, it's rendered a simply empty tin can.

No forces do not push against the atmosphere, in fact the atmosphere makes rockets inefficient, you are looking at reality the wrong way round.

Quote

It's you that is looking at it the wrong way round. The reasons why rockets work on Earth is because of the atmosphere. It isn't the most efficient way to travel on Earth but it is the fastest.

Yes it is more efficient than other modes of travel, this is because of air  having less friction (not more), but space is more efficient than that because there is no friction.

Quote from: Mantaxi on November 30, 2012, 10:17:28 AM

Quote from: sceptimatic on November 30, 2012, 10:15:17 AM

Quote from: Kendrick on November 30, 2012, 10:10:26 AM

Quote from: sceptimatic on November 30, 2012, 10:00:19 AM

The pressures on both sides cannot create equality because there is no pressure whatsoever in the vacuum of space to do that, so all you have is pressure coming from the rocket and the minute it leaves the rocket, it is swallowed up by space.

Space is neither hot or cold, so it has no preference what it's swallowing up.

Sorry - i think I may have confused you by providing too much detail.

You are in error in thinking that the vacuum 'swallows up' expanding gasses eliminating force from the equation.

I'm not in error. You are in error because you are relying on what you have been brainwashed to rely on and are sticking to it like glue, which is fine by me as I won;t be pushed off course by any pressure acting upon me, like your fake working space rockets.

If you want to prove anything to me, you better do a hell of a lot better or just accept you are wrong and have been fooled.

Ok explain to us the alternative, which is consistent,  more comprehensive than the origincal explaination and which  is also easily falsifiable.

If you cannot do this I have no reason to question the already much more corroborated theory.

The alternative to what?

to what we have been "brainwashed"into thinking...



[edit] in scare quotes because noobs like these tend to go "so you admit you have been brainwashed"

Carry on like this and you will be ignored. Your choice.

Do you believe you doing the members of this form a courtesy by asking for help to understand physics concepts then abruptly calling us brainwashed?

This is extremely rude behavior.

Quote from: Mantaxi on November 30, 2012, 10:21:19 AM

Quote from: sceptimatic on November 30, 2012, 10:19:11 AM

Quote from: Mantaxi on November 30, 2012, 10:12:53 AM

Quote from: sceptimatic on November 30, 2012, 10:09:10 AM

The gases cannot just push the rocket without an external force to act against.

This assumption is wrong
The force is created by the fuel and fire which explodes creating particles in space, and the particles momentum collides with the container causing a transfer of energy.

Quote

Please tell me you haven't stooped to this level.

Quote from: sceptimatic on November 30, 2012, 10:09:10 AM

On Earth it has that. It's called atmosphere.
In space, it's rendered a simply empty tin can.

No forces do not push against the atmosphere, in fact the atmosphere makes rockets inefficient, you are looking at reality the wrong way round.

Quote

It's you that is looking at it the wrong way round. The reasons why rockets work on Earth is because of the atmosphere. It isn't the most efficient way to travel on Earth but it is the fastest.

Yes it is more efficient than other modes of travel, this is because of air  having less friction (not more), but space is more efficient than that because there is no friction.

Space has nothing, so it's useless.

let me give you an alternate scenario, what is your mind made out of, how can you think and go from one thopugh to another if there is nothing to push against, mind has nothing. I realize I am being fecetious, but this guy is a dumbass.

Quote from: Mantaxi on November 30, 2012, 10:23:34 AM

Quote from: sceptimatic on November 30, 2012, 10:21:58 AM

Quote from: Mantaxi on November 30, 2012, 10:17:28 AM

Quote from: sceptimatic on November 30, 2012, 10:15:17 AM

Quote from: Kendrick on November 30, 2012, 10:10:26 AM

Quote from: sceptimatic on November 30, 2012, 10:00:19 AM

The pressures on both sides cannot create equality because there is no pressure whatsoever in the vacuum of space to do that, so all you have is pressure coming from the rocket and the minute it leaves the rocket, it is swallowed up by space.

Space is neither hot or cold, so it has no preference what it's swallowing up.

Sorry - i think I may have confused you by providing too much detail.

You are in error in thinking that the vacuum 'swallows up' expanding gasses eliminating force from the equation.

I'm not in error. You are in error because you are relying on what you have been brainwashed to rely on and are sticking to it like glue, which is fine by me as I won;t be pushed off course by any pressure acting upon me, like your fake working space rockets.

If you want to prove anything to me, you better do a hell of a lot better or just accept you are wrong and have been fooled.

Ok explain to us the alternative, which is consistent,  more comprehensive than the origincal explaination and which  is also easily falsifiable.

If you cannot do this I have no reason to question the already much more corroborated theory.

The alternative to what?

to what we have been brainwashed into thinking...

It isn't an alternative, it's how rockets work against what you have been told.

They work by pushing hot gases with force against the atmosphere under it and it's as simple as that.

It does not constantly kick itself up the arse end to do it.

how do things move in space.

Do you believe that space ahs an atmosphere?

Quote from: ThinkingMan on November 30, 2012, 10:13:50 AM

Quote from: sceptimatic on November 30, 2012, 10:09:10 AM

Quote from: robertotrevor on November 30, 2012, 10:00:29 AM

Quote from: sceptimatic on November 30, 2012, 09:57:32 AM

Quote from: robertotrevor on November 30, 2012, 09:51:55 AM

The explosion itself its already creating force to create expansion. The force making the rocket move is that expansion against the rocket, mass causing pressure against mass.
The rocket moves because of the expansion of gasses against the rocket, not against the vacuum.

The point is where the explosion would be. Is not an accurate representation of a rocket, just to show the forces.

This is exactly you saying that the rocket pushes against itself with the exhaust having no part in it.
It's so silly , it's actually scary to think people believe this.

You don't get it, the exhaust against vacuum does nothing, but there are also gases moving against the rocket. The gasses push the rocket so it moves, is not the rocket against the rocket because this gases are not attached to the rocket and are constantly leaving it.

Have a word will you.

The gases cannot just push the rocket without an external force to act against.
On Earth it has that. It's called atmosphere.
In space, it's rendered a simply empty tin can.

Why don't you push against the atmosphere and see how far you get?

Give me a helicopter and I will.

A helicopter does not push anything. It's blades are designed to create a force known as lift, which is not the way a rocket works. Rockets do not have spinning rotors. They have a combustion chamber... and it has been explained how that works.

EDIT: Time for me to fade back into the background.

Quote from: Kendrick on November 30, 2012, 10:27:27 AM

Quote from: sceptimatic on November 30, 2012, 10:22:59 AM

Carry on like this and you will be ignored. Your choice.

Do you believe you doing the members of this form a courtesy by asking for help to understand physics concepts then abruptly calling us brainwashed?

This is extremely rude behavior.

Do you think it's clever to try  your little put down?

We are all brainwashed in life, so it's hardly a dig.
We are all brought up on manipulation and lies, it just so happens that when we grow up, we have to sift through what we have been forced to accept as true and what our own logic tells us could be manipulation.

We have all, (hopefully) figured out the tooth fairy is BS and Santa, yet we allow our small children to still believe in them, because it makes them happy.

We even manipulate our own children but we see it as a good cause.

The problem with some people as they get older is, they still dine out on stuff that is blatantly false, like moon landings and once you see that, you just know they will swallow anything told to them, regardless of how intelligent they say they are.

Either that or they know it's BS but care more to protect it.

Brainwashing is a very unscientific term. you used it originally as a shaming tactic and troll, now when you have been called out on it, you accuse kendrick (who has been nothing but respectful to you) of "putting you down" and then you change the conext of your shaming tactic to "everyone is brainwashed",  so you expect us all to believe that you did not do it originially to be a contrarian little bitch? if you beleive we are all brainwashed, then nothing you say is worth anything, at all.

you poor sad, little turd.

Quote from: ThinkingMan on November 30, 2012, 10:36:42 AM

Quote from: sceptimatic on November 30, 2012, 10:20:55 AM

Quote from: ThinkingMan on November 30, 2012, 10:13:50 AM

Quote from: sceptimatic on November 30, 2012, 10:09:10 AM

Quote from: robertotrevor on November 30, 2012, 10:00:29 AM

Quote from: sceptimatic on November 30, 2012, 09:57:32 AM

Quote from: robertotrevor on November 30, 2012, 09:51:55 AM

The explosion itself its already creating force to create expansion. The force making the rocket move is that expansion against the rocket, mass causing pressure against mass.
The rocket moves because of the expansion of gasses against the rocket, not against the vacuum.

The point is where the explosion would be. Is not an accurate representation of a rocket, just to show the forces.

This is exactly you saying that the rocket pushes against itself with the exhaust having no part in it.
It's so silly , it's actually scary to think people believe this.

You don't get it, the exhaust against vacuum does nothing, but there are also gases moving against the rocket. The gasses push the rocket so it moves, is not the rocket against the rocket because this gases are not attached to the rocket and are constantly leaving it.

Have a word will you.

The gases cannot just push the rocket without an external force to act against.
On Earth it has that. It's called atmosphere.
In space, it's rendered a simply empty tin can.

Why don't you push against the atmosphere and see how far you get?

Give me a helicopter and I will.

A helicopter does not push anything. It's blades are designed to create a force known as lift, which is not the way a rocket works. Rockets do not have spinning rotors. They have a combustion chamber... and it has been explained how that works.

EDIT: Time for me to fade back into the background.

How do you think the blades create lift?

Downward force that's how.

Okay, I'll fade away after this brief response. They create lift from the shape of the blade and the way it moves laterally through the air, which creates a "pillow" of air underneath the blade. If the blade is angled properly and moving the right speed, it will live the craft underneath it. It works the same way with airplane wings. You're not going to tell me that wings create a downward force are you? Good, because that would just be ridiculous.

Hey Sceptimatic, despite saying bye earlier, I have an experiment and visual aid for you to try should you feel up to it.

Unlike the vacuum chamber, or even the balloons, this one should take minimal resources and setup time.

1. Take an empty, lidless shoebox.

2. Place both hands in the shoebox.

3. Move hands outward and press against the ends (simulating internal pressure, i.e. combustion, etc).

4. Note that while applying internal pressure to both ends, the box does not move either direction. 

5. Now, cut an opening in one end.

6. Again place your hands in the box and begin applying pressure outward against the ends.

7. Note that one hand exits the box through the opening and is pushing against nothing, while the other hand is pushing the box and moving it.

Obviously this only simulates pressure to the front and back, as you're not applying equal force to the bottom, sides, or (open anyway) top.