HAPPY HOAX ANNIVERSARY!!! (Rockets can't fly in a vacuum)

Nope! The simplest of physics dictates that rockets develop thrust quite independent of any atmosphere!
All you need is force = mass x acceleration and voila, you have your basic thrust equation and it works!

Force equals mass times acceleration means nothing unless you put it up against external atmosphere, then you have your force by internal verses external gaseous/fluid fight to accelerate your mass.

It doesn't work in your fictional vacuum and barely works in extreme low pressure and for a reason.

Quote from: Macarios on December 14, 2019, 02:30:40 AM

Quote from: sceptimatic on December 14, 2019, 02:10:34 AM

Quote from: Stash on December 13, 2019, 01:06:15 PM

Yeah, there is this huge gaping hole in the Sceptimatic notion - And JB has brought it up a million times. If the gas 'unfurls', expands, or whatever and pushes off itself when leaving the rocket it would be pushing the rocket as well.

Literally, the Scepti notion shows that rockets work in a vacuum rather than not.

Everything I'm saying  works from my side. You and other not or refusing to understand it is a problem you need to fix to save you wasting your time.

Everuthing?

A portion of the gas in chamber, before it became exhaust, had the speed zero.
That portion also has non-zero mass.
To get out, the mass of the exhaust-to-be has to gain some speed.
To reach that speed it needs acceleration.
And for the acceleration it needs force.
The remaining gas inside gives that force as action, and receives reaction force from the exhaust-to-be.
The reaction force pushes the remaining gas in the opposite direction and gives it the proportional acceleration.
The remainin gas can't can't stay in place without support from something else.
That something else are the walls of the chamber that give action force to the remaining gas.
The remaining gas exerts the reaction force on the chamber.
In vacuum of space the chamber (and the whole rocket) has no support to resist that reaction and stay in place.
That's why the rocket can't stay where it was.

Let's try something.

If you were to run into a closed door not on a latch would you push that door open before that door could stop you in your tracks?

The answer should be yes.

So what if there was a massive sponge against that door and about 10 feet thick away from it and you ran at that sponge. What do you think would happen.

Believe me I'm  getting to a point but I need you to answer the questions.

Is there sponge in the room to push me out through that door, or I run out on my own?

Quote from: Stash on December 13, 2019, 12:25:43 AM

There's a problem here. You claim that as the gas is escaping it's no longer pushing on the pressure gauge. But when you close the valve, the gas presses on the gauge and you get a pressure reading.

Only if there's gauge pressure inside the container as you close the valve, It will then stop expanding out of the valve and immediately be rendered equalised meaning it tries to expand against all sides.

Again, this is where your musing fails. Gas doesn't just stop expanding in all directions because you create an opening at one end of a container. If that were the case, like mentioned many times before, as soon as the valve is opened the gauge would literally drop to zero. It doesn't. It lowers in direct correspondence to the amount of gas/pressure released. If the valve is halfway open, the gauge will slowly go down. If the gauge is opened 3/4 of the way, the gauge will go down quicker, accordingly.
There's a direct correlation between how/what the gauge reads and the amount of and at what rate the gas is being released. The only way for that to occur is for the gas to still be pressing on the gauge. i.e., expansion. There's no other way around that fact I'm afraid.

Most things are a hypothesis and some things are misin/disinformation.

Well at least you are now admitting that you are intentionally spreading misinformation.

It's all about deciphering what can be potentially legit and what can actually be legit.
Not an easy task for those trying to get past mainstream ideals.

Yes, it is quite hard for those trying to reject reality to find things which are legit.
Look at how hard it is for you, still not being able to answer a very simple question, all because you need to reject the conclusion of that question.

Simple common sense should tell anyone that rockets need an atmosphere in order to work.

Except as clearly shown by your repeated avoidance of a simple question, IT DOESN'T!
Instead, simple common sense shows that it isn't needed at all.

Gas, like I said.

Again, that doesn't address the issue.
You can't just say a single word like that. You need to explain how the gas can push off something when you claim there is nothing there to push off, which in facts means there is something there to push off, which means there is something there for the rocket to push off.

If the gas leaving the rocket is capable of using the gas inside the rocket as leverage, then why can't the rocket?

If you bothered to pay attention you wouldn't need to type so much and have it ignored.

You mean I would realise you have absolutely no interest in the truth and I would just stop posting because I know you will honestly address the issue as it shows you are completely wrong and you have absolutely no rational nor honest way out?
If so, no, I am quite aware of that.

Perhaps you should try paying attention to what the actual issue is and then address that?

Perhaps I should try another question?
Is there anything in space for things to push off to move, or will they be unable to move as there is nothing to push off?

Again you have the same impossible situation for your insane claims, if the former, that means rockets work. If the later, that means the gas can't leave the rocket.

Force equals mass times acceleration means nothing unless you put it up against external atmosphere

So you are saying the gas can't accelerate out of the rocket as there is no external atmosphere to push off?
So the lack of an atmosphere magically keeps high pressure gas trapped inside an open container exposed to the vacuum?

Again, if simple common sense indicated that rockets can't work in a vacuum you should easily be able to address this issue, but you can't. Instead you just repeatedly contradict yourself by claiming the rocket can't accelerate in a vacuum because there is nothing to push off and there is no atmosphere, but the gas magically finds a way and pushes of something and manages to accelerate even though there is no atmosphere.

Again, you can't have it both ways.
Either rockets work in space, or gas stays trapped in an open container. Which is it?

Is there sponge in the room to push me out through that door, or I run out on my own?

You run at it on your own, under your own energy.

Explain what would happen.

Quote from: sceptimatic on December 13, 2019, 05:59:03 AM

Quote from: Stash on December 13, 2019, 12:25:43 AM

There's a problem here. You claim that as the gas is escaping it's no longer pushing on the pressure gauge. But when you close the valve, the gas presses on the gauge and you get a pressure reading.

Only if there's gauge pressure inside the container as you close the valve, It will then stop expanding out of the valve and immediately be rendered equalised meaning it tries to expand against all sides.

Again, this is where your musing fails. Gas doesn't just stop expanding in all directions because you create an opening at one end of a container. If that were the case, like mentioned many times before, as soon as the valve is opened the gauge would literally drop to zero. It doesn't. It lowers in direct correspondence to the amount of gas/pressure released. If the valve is halfway open, the gauge will slowly go down. If the gauge is opened 3/4 of the way, the gauge will go down quicker, accordingly.
There's a direct correlation between how/what the gauge reads and the amount of and at what rate the gas is being released. The only way for that to occur is for the gas to still be pressing on the gauge. i.e., expansion. There's no other way around that fact I'm afraid.

Because after all this time you still haven't grasped what I put forward. You simply haven't and you can sit and argue that you have all day long. You cannot grasp what I'm telling you. If that's deliberate then fair enough but it's your time you're wasting by playing this game.
If you genuinely don't get it then you need to pay more attention.

Again, that doesn't address the issue.

It does.

Quote from: Macarios on December 14, 2019, 11:04:44 AM

Is there sponge in the room to push me out through that door, or I run out on my own?

You run at it on your own, under your own energy.

Explain what would happen.

If I run on my own, I can decide not to.

If I run on my own (unlike gas in chamber), my feet would push the floor backwards.
If the room is fixed to the ground, room floor (and the whole room) would have support and wouldn't move.
If the room was at some boat, it would move backward with momentum equal to
my momentum forward, minus the water drag.

Door opened or closed have no influence. (Rocket apperture and nozzle are always open.)

After I go through the door I could decide if I will keep running those 10 feet across the dirt in front.
From that point on, my movement has no further influence on the room.

If I later run into the sponge, it would compress where my body hits it.

Quote from: sceptimatic on December 15, 2019, 04:53:18 AM

Quote from: Macarios on December 14, 2019, 11:04:44 AM

Is there sponge in the room to push me out through that door, or I run out on my own?

You run at it on your own, under your own energy.

Explain what would happen.

If I run on my own, I can decide not to.

If I run on my own (unlike gas in chamber), my feet would push the floor backwards.
If the room is fixed to the ground, room floor (and the whole room) would have support and wouldn't move.
If the room was at some boat, it would move backward with momentum equal to
my momentum forward, minus the water drag.

Door opened or closed have no influence. (Rocket apperture and nozzle are always open.)

After I go through the door I could decide if I will keep running those 10 feet across the dirt in front.
From that point on, my movement has no further influence on the room.

If I later run into the sponge, it would compress where my body hits it.

I knew it was a complete waste of time with you but I gave you a shot.

Quote from: Macarios on December 15, 2019, 07:17:03 AM

Quote from: sceptimatic on December 15, 2019, 04:53:18 AM

Quote from: Macarios on December 14, 2019, 11:04:44 AM

Is there sponge in the room to push me out through that door, or I run out on my own?

You run at it on your own, under your own energy.

Explain what would happen.

If I run on my own, I can decide not to.

If I run on my own (unlike gas in chamber), my feet would push the floor backwards.
If the room is fixed to the ground, room floor (and the whole room) would have support and wouldn't move.
If the room was at some boat, it would move backward with momentum equal to
my momentum forward, minus the water drag.

Door opened or closed have no influence. (Rocket apperture and nozzle are always open.)

After I go through the door I could decide if I will keep running those 10 feet across the dirt in front.
From that point on, my movement has no further influence on the room.

If I later run into the sponge, it would compress where my body hits it.

I knew it was a complete waste of time with you but I gave you a shot.

Yes you gave him a shot, but he would rather have the money from his bosses not to understand.

Quote from: Macarios on December 15, 2019, 07:17:03 AM

Quote from: sceptimatic on December 15, 2019, 04:53:18 AM

Quote from: Macarios on December 14, 2019, 11:04:44 AM

Is there sponge in the room to push me out through that door, or I run out on my own?

You run at it on your own, under your own energy.

Explain what would happen.

If I run on my own, I can decide not to.

If I run on my own (unlike gas in chamber), my feet would push the floor backwards.
If the room is fixed to the ground, room floor (and the whole room) would have support and wouldn't move.
If the room was at some boat, it would move backward with momentum equal to
my momentum forward, minus the water drag.

Door opened or closed have no influence. (Rocket apperture and nozzle are always open.)

After I go through the door I could decide if I will keep running those 10 feet across the dirt in front.
From that point on, my movement has no further influence on the room.

If I later run into the sponge, it would compress where my body hits it.

I knew it was a complete waste of time with you but I gave you a shot.

You gave a shot to someone? LOL

We are very patient with you trying to point out where and how
your wishes are different from the real operating principle of a rocket.

Quote from: Macarios on December 14, 2019, 11:04:44 AM

Is there sponge in the room to push me out through that door, or I run out on my own?

You run at it on your own, under your own energy.

Explain what would happen.

You would run into the door and bounce off as the door isn't open.  What do you think would happen?

Because after all this time you still haven't grasped what I put forward.

No, we grasp it quite well, we just realise it is pure nonsense.

Not accepting your BS doesn't mean we don't grasp it.

It does.

The only way for it to address the issue is if you accept that it means that there is something to use as leverage/push against and thus that rockets can work in a vacuum.

If you disagree, then it doesn't address the issue at all.
Again, you need to explain how the gas can move while the rocket can't.
You need to identify what the gas is pushing against and clearly explain why that doesn't allow the rocket to move.

Again, there are really only 4 options:
1 - Nothing - As you assert in your argument against rockets working, there is absolutely nothing to push against and thus the gas CANNOT move.
2 - Itself - This means your argument is wrong, and the rocket can push against itself to move and thus rockets work in a vacuum.
3 - The rocket - This means the gas is pushing against the rocket and thus the rocket will move and thus rockets work in a vacuum.
4 - Something else - This means there is something that both the gas and the rocket can push against to move and thus rockets work in a vacuum.

Again, it all boils down to 2 options:
Rockets work in a vacuum or the gas is magically trapped in an open container.
Which is it?

Quote from: sceptimatic on December 15, 2019, 10:32:19 AM

Quote from: Macarios on December 15, 2019, 07:17:03 AM

Quote from: sceptimatic on December 15, 2019, 04:53:18 AM

Quote from: Macarios on December 14, 2019, 11:04:44 AM

Is there sponge in the room to push me out through that door, or I run out on my own?

You run at it on your own, under your own energy.

Explain what would happen.

If I run on my own, I can decide not to.

If I run on my own (unlike gas in chamber), my feet would push the floor backwards.
If the room is fixed to the ground, room floor (and the whole room) would have support and wouldn't move.
If the room was at some boat, it would move backward with momentum equal to
my momentum forward, minus the water drag.

Door opened or closed have no influence. (Rocket apperture and nozzle are always open.)

After I go through the door I could decide if I will keep running those 10 feet across the dirt in front.
From that point on, my movement has no further influence on the room.

If I later run into the sponge, it would compress where my body hits it.

I knew it was a complete waste of time with you but I gave you a shot.

Yes you gave him a shot, but he would rather have the money from his bosses not to understand.

It seems like that doesn't it.

Quote from: sceptimatic on December 15, 2019, 04:53:18 AM

Quote from: Macarios on December 14, 2019, 11:04:44 AM

Is there sponge in the room to push me out through that door, or I run out on my own?

You run at it on your own, under your own energy.

Explain what would happen.

You would run into the door and bounce off as the door isn't open.  What do you think would happen?

Did you not get the " not on a latch" bit?

Rockets work in a vacuum.

No they don't.

Quote from: Stash on December 14, 2019, 11:51:48 PM

Quote from: sceptimatic on December 13, 2019, 05:59:03 AM

Quote from: Stash on December 13, 2019, 12:25:43 AM

There's a problem here. You claim that as the gas is escaping it's no longer pushing on the pressure gauge. But when you close the valve, the gas presses on the gauge and you get a pressure reading.

Only if there's gauge pressure inside the container as you close the valve, It will then stop expanding out of the valve and immediately be rendered equalised meaning it tries to expand against all sides.

Again, this is where your musing fails. Gas doesn't just stop expanding in all directions because you create an opening at one end of a container. If that were the case, like mentioned many times before, as soon as the valve is opened the gauge would literally drop to zero. It doesn't. It lowers in direct correspondence to the amount of gas/pressure released. If the valve is halfway open, the gauge will slowly go down. If the gauge is opened 3/4 of the way, the gauge will go down quicker, accordingly.
There's a direct correlation between how/what the gauge reads and the amount of and at what rate the gas is being released. The only way for that to occur is for the gas to still be pressing on the gauge. i.e., expansion. There's no other way around that fact I'm afraid.

Because after all this time you still haven't grasped what I put forward. You simply haven't and you can sit and argue that you have all day long. You cannot grasp what I'm telling you. If that's deliberate then fair enough but it's your time you're wasting by playing this game.
If you genuinely don't get it then you need to pay more attention.

It's not that I haven't 'grasped' what you've put forward. It's just that what you've put forward fails to make sense in reality. How would the gauge go down at the speed corresponding with how much the valve is opened if there was nothing pressing on the gauge?

If I open the valve all the way the gauge will go down faster than if I open the valve only halfway. How does the gauge know to make that corresponding adjustment if there's nothing pressing on the gauge to cause a reading? Because, you know, that's how the millions of pressure gauges in the world work.

Quote from: JackBlack on December 15, 2019, 12:41:41 PM

Rockets work in a vacuum.

No they don't.

QFT

Quote from: JackBlack on December 15, 2019, 12:41:41 PM

Rockets work in a vacuum .

No they don't .

Yes they do work .

Quote from: sceptimatic on December 15, 2019, 01:36:31 PM

Quote from: JackBlack on December 15, 2019, 12:41:41 PM

Rockets work in a vacuum.

No they don't.

QFT

Hoppy, a word of advice! Don't venture into the upper fora or you might get lost.

It seems like that doesn't it.

Not to any sane, logical person.
To them it looks like you are still avoiding very simple questions and issues which show your claims to be nothing more than fantasy.

So far all you have done amounts to nothing more than just baselessly asserting that rockets don't work in a vacuum.
You are yet to substantiate your claim in any way.
In fact, you have directly contradicted your own arguments rockets not working in space.


If you want to honestly and rationally claim that rockets cannot work in a vacuum then you need to deal with the issue you have been avoiding since it was brought up.
Again, do you accept that if you have a tube of compressed gas, in a vacuum, with one end open that the gas will leave the tube?
If so, as you claim that such motion is impossible in space as there is no atmosphere to push off, just how is the gas leaving? What is it pushing off which magically works for the gas but not the rocket?

Dismiss these argument which show you have no case at all, just further shows you have no case.

Quote from: sceptimatic on December 15, 2019, 04:55:34 AM

Quote from: Stash on December 14, 2019, 11:51:48 PM

Quote from: sceptimatic on December 13, 2019, 05:59:03 AM

Quote from: Stash on December 13, 2019, 12:25:43 AM

There's a problem here. You claim that as the gas is escaping it's no longer pushing on the pressure gauge. But when you close the valve, the gas presses on the gauge and you get a pressure reading.

Only if there's gauge pressure inside the container as you close the valve, It will then stop expanding out of the valve and immediately be rendered equalised meaning it tries to expand against all sides.

Again, this is where your musing fails. Gas doesn't just stop expanding in all directions because you create an opening at one end of a container. If that were the case, like mentioned many times before, as soon as the valve is opened the gauge would literally drop to zero. It doesn't. It lowers in direct correspondence to the amount of gas/pressure released. If the valve is halfway open, the gauge will slowly go down. If the gauge is opened 3/4 of the way, the gauge will go down quicker, accordingly.
There's a direct correlation between how/what the gauge reads and the amount of and at what rate the gas is being released. The only way for that to occur is for the gas to still be pressing on the gauge. i.e., expansion. There's no other way around that fact I'm afraid.

Because after all this time you still haven't grasped what I put forward. You simply haven't and you can sit and argue that you have all day long. You cannot grasp what I'm telling you. If that's deliberate then fair enough but it's your time you're wasting by playing this game.
If you genuinely don't get it then you need to pay more attention.

It's not that I haven't 'grasped' what you've put forward. It's just that what you've put forward fails to make sense in reality. How would the gauge go down at the speed corresponding with how much the valve is opened if there was nothing pressing on the gauge?

If I open the valve all the way the gauge will go down faster than if I open the valve only halfway. How does the gauge know to make that corresponding adjustment if there's nothing pressing on the gauge to cause a reading? Because, you know, that's how the millions of pressure gauges in the world work.

If you open the valve more you allow more molecules to expand out meaning the faster they all start to follow suit, meaning the gauge spring pushes faster, meaning the gauge needle shows a faster rate of pressure release.

Again, do you accept that if you have a tube of compressed gas, in a vacuum extreme low pressure, with one end open that the gas will leave the tube?

Most of it but not all of it.

If so, as you claim that such motion is impossible in space as there is no atmosphere to push off, just how is the gas leaving? What is it pushing off which magically works for the gas but not the rocket?

It's own expansion from being compressed, like I told you.

Dismiss these argument which show you have no case at all, just further shows you have no case.

I've not only not dismissed them I've told you enough times already. It's you that dismisses them and is why you generally get very little answers when you repeat the same thing.

Quote from: NotSoSkeptical on December 15, 2019, 12:24:06 PM

Quote from: sceptimatic on December 15, 2019, 04:53:18 AM

Quote from: Macarios on December 14, 2019, 11:04:44 AM

Is there sponge in the room to push me out through that door, or I run out on my own?

You run at it on your own, under your own energy.

Explain what would happen.

You would run into the door and bounce off as the door isn't open.  What do you think would happen?

Did you not get the " not on a latch" bit?

Read the above quote and tell me prior to you saying "not on a latch", where does it say "not on a latch" in what I quoted.

As well, why not say the door is open.

And a door not latched does not mean open.

Quote from: sceptimatic on December 15, 2019, 01:35:04 PM

Quote from: NotSoSkeptical on December 15, 2019, 12:24:06 PM

Quote from: sceptimatic on December 15, 2019, 04:53:18 AM

Quote from: Macarios on December 14, 2019, 11:04:44 AM

Is there sponge in the room to push me out through that door, or I run out on my own?

You run at it on your own, under your own energy.

Explain what would happen.

You would run into the door and bounce off as the door isn't open.  What do you think would happen?

Did you not get the " not on a latch" bit?

Read the above quote and tell me prior to you saying "not on a latch", where does it say "not on a latch" in what I quoted.

As well, why not say the door is open.

And a door not latched does not mean open.

But a door not on a latch can still be closed.

Quote from: NotSoSkeptical on December 16, 2019, 07:20:48 AM

Quote from: sceptimatic on December 15, 2019, 01:35:04 PM

Quote from: NotSoSkeptical on December 15, 2019, 12:24:06 PM

Quote from: sceptimatic on December 15, 2019, 04:53:18 AM

Quote from: Macarios on December 14, 2019, 11:04:44 AM

Is there sponge in the room to push me out through that door, or I run out on my own?

You run at it on your own, under your own energy.

Explain what would happen.

You would run into the door and bounce off as the door isn't open.  What do you think would happen?

Did you not get the " not on a latch" bit?

Read the above quote and tell me prior to you saying "not on a latch", where does it say "not on a latch" in what I quoted.

As well, why not say the door is open.

And a door not latched does not mean open.

But a door not on a latch can still be closed.

And what happens when you run into a closed door?

Quote from: sceptimatic on December 16, 2019, 07:22:10 AM

Quote from: NotSoSkeptical on December 16, 2019, 07:20:48 AM

Quote from: sceptimatic on December 15, 2019, 01:35:04 PM

Quote from: NotSoSkeptical on December 15, 2019, 12:24:06 PM

Quote from: sceptimatic on December 15, 2019, 04:53:18 AM

Quote from: Macarios on December 14, 2019, 11:04:44 AM

Is there sponge in the room to push me out through that door, or I run out on my own?

You run at it on your own, under your own energy.

Explain what would happen.

You would run into the door and bounce off as the door isn't open.  What do you think would happen?

Did you not get the " not on a latch" bit?

Read the above quote and tell me prior to you saying "not on a latch", where does it say "not on a latch" in what I quoted.

As well, why not say the door is open.

And a door not latched does not mean open.

But a door not on a latch can still be closed.

And what happens when you run into a closed door?

If you had just took notice instead of going into skew tactics I would've got to it but you're not worth the effort to be fair.

Quote from: NotSoSkeptical on December 16, 2019, 07:32:00 AM

Quote from: sceptimatic on December 16, 2019, 07:22:10 AM

Quote from: NotSoSkeptical on December 16, 2019, 07:20:48 AM

Quote from: sceptimatic on December 15, 2019, 01:35:04 PM

Quote from: NotSoSkeptical on December 15, 2019, 12:24:06 PM

Quote from: sceptimatic on December 15, 2019, 04:53:18 AM

Quote from: Macarios on December 14, 2019, 11:04:44 AM

Is there sponge in the room to push me out through that door, or I run out on my own?

You run at it on your own, under your own energy.

Explain what would happen.

You would run into the door and bounce off as the door isn't open.  What do you think would happen?

Did you not get the " not on a latch" bit?

Read the above quote and tell me prior to you saying "not on a latch", where does it say "not on a latch" in what I quoted.

As well, why not say the door is open.

And a door not latched does not mean open.

But a door not on a latch can still be closed.

And what happens when you run into a closed door?

If you had just took notice instead of going into skew tactics I would've got to it but you're not worth the effort to be fair.

I didn't skew anything.

Nice deflection though.  Why don't you just answer the questions instead of deflecting and running away.  You want people to "grasp" your reasoning, then stop running from questions.

If you open the valve more you allow more molecules to expand out meaning the faster they all start to follow suit, meaning the gauge spring pushes faster, meaning the gauge needle shows a faster rate of pressure release.

Because the pressure inside is decreasing faster.
If the gas wasn't still pushing on the gauge, how quickly the gas left wouldn't matter.

Most of it but not all of it.

Which means your prior claims about motion in this vacuum are completley wrong as if they were true, it couldn't leave.

Quote from: JackBlack

If so, as you claim that such motion is impossible in space as there is no atmosphere to push off, just how is the gas leaving? What is it pushing off which magically works for the gas but not the rocket?

It's own expansion from being compressed, like I told you.

You mean like you have repeatedly avoided the issue?
"its own expansion" doesn't tell me what it is pushing off.
Nor does it tell me how it and only it manages to move without the atmosphere.

Again, either there is no atmosphere and nothing to push against so nothing can move, or your claims about rockets not working are pure garbage.

Again, in order to actually address the issue you need to tell us what the gas is pushing off and why that doesn't mean the rocket has something to push off.

I've not only not dismissed them I've told you enough times already. It's you that dismisses them and is why you generally get very little answers when you repeat the same thing.

Telling me you have dismissed them doesn't help either.
You need to actually refute them.
You need to deal with the issues raised.

I haven't dismissed what you have said, I have refuted it.

The reason I generally get very little answers from you is because you cannot answer as the question shows a fundamental flaw with your argument and you don't care about the truth or having a model which can actually describe reality.
So instead all you provide are pathetic non-answers or you otherwise avoiding the issue.

Why don't you try providing an honest, rational answer for once?

Again, is there nothing to push against in the vacuum meaning the rocket can't move? If so, the same applies to the gas and thus the gas can't leave the tube.
In order for the gas to be able to leave the tube it needs something to push against, which means there is something to push against, even in a vacuum, and thus rockets can work in a vacuum.

Quote from: Stash on December 15, 2019, 02:27:18 PM

Quote from: sceptimatic on December 15, 2019, 04:55:34 AM

Quote from: Stash on December 14, 2019, 11:51:48 PM

Quote from: sceptimatic on December 13, 2019, 05:59:03 AM

Quote from: Stash on December 13, 2019, 12:25:43 AM

There's a problem here. You claim that as the gas is escaping it's no longer pushing on the pressure gauge. But when you close the valve, the gas presses on the gauge and you get a pressure reading.

Only if there's gauge pressure inside the container as you close the valve, It will then stop expanding out of the valve and immediately be rendered equalised meaning it tries to expand against all sides.

Again, this is where your musing fails. Gas doesn't just stop expanding in all directions because you create an opening at one end of a container. If that were the case, like mentioned many times before, as soon as the valve is opened the gauge would literally drop to zero. It doesn't. It lowers in direct correspondence to the amount of gas/pressure released. If the valve is halfway open, the gauge will slowly go down. If the gauge is opened 3/4 of the way, the gauge will go down quicker, accordingly.
There's a direct correlation between how/what the gauge reads and the amount of and at what rate the gas is being released. The only way for that to occur is for the gas to still be pressing on the gauge. i.e., expansion. There's no other way around that fact I'm afraid.

Because after all this time you still haven't grasped what I put forward. You simply haven't and you can sit and argue that you have all day long. You cannot grasp what I'm telling you. If that's deliberate then fair enough but it's your time you're wasting by playing this game.
If you genuinely don't get it then you need to pay more attention.

It's not that I haven't 'grasped' what you've put forward. It's just that what you've put forward fails to make sense in reality. How would the gauge go down at the speed corresponding with how much the valve is opened if there was nothing pressing on the gauge?

If I open the valve all the way the gauge will go down faster than if I open the valve only halfway. How does the gauge know to make that corresponding adjustment if there's nothing pressing on the gauge to cause a reading? Because, you know, that's how the millions of pressure gauges in the world work.

If you open the valve more you allow more molecules to expand out meaning the faster they all start to follow suit, meaning the gauge spring pushes faster, meaning the gauge needle shows a faster rate of pressure release.

What's the gauge spring pushing faster against?