[Tumeni]

somerled - a thought experiment - take a standard tin can, such as you would find on a supermarket shelf with soup, beans or similar, and imagine you have filled it with rocket fuel, and you can ignite it remotely. No air within, just fuel.

You place it in a vacuum, and ignite the fuel.

There can only be one of two results, given that
"1 Energy stored in fuel =>
2 chemical reaction =>
3 lots of gas (and heat) produced =>
4 increased pressure  within  =>
5 physical reaction =>
6 gas gets "pushed" against internal walls


Result 1 - the walls are strong enough to hold, and the reaction is contained
Result 2 - the walls cannot do this, and the can ruptures at its weakest point

Agree?

[AATW]

So, we do not know if the gauge used was or wasn't experiencing any of the issues described by the source above

What we do know is that the gauge clearly moves as he evacuates the chamber



So it is not malfunctioning.
I note you have quoted the part of the document I posted. Note how it doesn't say anything about the gauge malfunctioning, it actually cautions people not to tap too hard so the gauge does not break.

Sorry, I am not latching on to a stupid argument. It is a legitimate argument.

It's not an argument at all, it's a diversion at best.

And the videos posted by those in agreement with your position absolutely destroy your rebuttal.
AATW now disagrees with you, as he admits these videos display rockets in operation in an environment that is NOT a vacuum.
The reason: Even he realizes that rockets cannot work in a vacuum.

Please do not deliberately misrepresent my position. Rockets work in a vacuum because of Newton's 3rd law.
I have explained about the gas ejected from rockets having momentum ad nauseum.
iCare has carefully explained why the free expansion result does not apply to rockets. I note you haven't addressed his points.
You haven't addressed mine either:

But actually in the videos posted which show the rocket working in both normal pressure and in a vacuum, you can see the rockets work pretty much the same. Even if we agree that it's not a perfect vacuum, the pressure is still low enough that you wouldn't expect the rocket to work anywhere near as well as at full atmospheric pressure if the rocket was working in the way you suppose.

So while I agree it might not be a perfect vacuum, it's close enough to demonstrate the principle.
If your assertion is that rockets work by "pushing off" the atmosphere then you'd expect the rocket to work far less efficiently when almost all the air is pumped out. That is not what is seen in those videos.

[totallackey]

So, we do not know if the gauge used was or wasn't experiencing any of the issues described by the source above

What we do know is that the gauge clearly moves as he evacuates the chamber



So it is not malfunctioning.

He was tapping on it and the only reason to tap on it is, according to your own source is:

The gauge is, might be>>>MALFUNCTIONING!

I note you have quoted the part of the document I posted. Note how it doesn't say anything about the gauge malfunctioning, it actually cautions people not to tap too hard so the gauge does not break.

Yeah, I did, and I have been quoting and or referring to the source ever since you provided it, much to your dismay.

Your own source states the reasons for tapping on a gauge.

Reasons>>> friction or loss of flexibility (i.e., MALFUNCTIONING)

Sorry, I am not latching on to a stupid argument. It is a legitimate argument.

It's not an argument at all, it's a diversion at best.

Not a diversion.

Quoting and referring readers to your source is NOT diverting them from your source.

And the videos posted by those in agreement with your position absolutely destroy your rebuttal.
AATW now disagrees with you, as he admits these videos display rockets in operation in an environment that is NOT a vacuum.
The reason: Even he realizes that rockets cannot work in a vacuum.

Please do not deliberately misrepresent my position. Rockets work in a vacuum because of Newton's 3rd law.
I have explained about the gas ejected from rockets having momentum ad nauseum.
iCare has carefully explained why the free expansion result does not apply to rockets. I note you haven't addressed his points.
You haven't addressed mine either:

But actually in the videos posted which show the rocket working in both normal pressure and in a vacuum, you can see the rockets work pretty much the same. Even if we agree that it's not a perfect vacuum, the pressure is still low enough that you wouldn't expect the rocket to work anywhere near as well as at full atmospheric pressure if the rocket was working in the way you suppose.

So while I agree it might not be a perfect vacuum, it's close enough to demonstrate the principle.
If your assertion is that rockets work by "pushing off" the atmosphere then you'd expect the rocket to work far less efficiently when almost all the air is pumped out. That is not what is seen in those videos.

I have addressed both you and ICare's points, using the videos YOU provided, which clearly show rockets NOT working in a vacuum.

When you admit it is not a vacuum, and I clearly stated AATW admits it is not a vacuum, then I am not misrepresenting your position.

You conceded the argument.

I argued > Rockets do not work in a vacuum.

You > finally agreed.

[somerled]

somerled - a thought experiment - take a standard tin can, such as you would find on a supermarket shelf with soup, beans or similar, and imagine you have filled it with rocket fuel, and you can ignite it remotely. No air within, just fuel.

You place it in a vacuum, and ignite the fuel.

There can only be one of two results, given that
"1 Energy stored in fuel =>
2 chemical reaction =>
3 lots of gas (and heat) produced =>
4 increased pressure  within  =>
5 physical reaction =>
6 gas gets "pushed" against internal walls


Result 1 - the walls are strong enough to hold, and the reaction is contained
Result 2 - the walls cannot do this, and the can ruptures at its weakest point

Agree?

Here is an excellent video by a serious researcher , Cody - not a flat earther but knows his stuff and researches diligently . Should be of interest to you and iCare . It's not long but  skip the first 5 if you want .


Uses a real vacuum chamber.

Once he completes his experiments it's quite a revelation that he mentions the fire triangle , was it iCare  that brought that up? He concludes that it should be a fire square , the fourth requirement being pressure .

To be fair to Cody , like all of us , I don't think we are told of Joules experiment at school , college or university ( I certainly wasn't ) and here he is confirming that law of free gas expansion into a vacuum, It's a fine experiment carried out without any tricks. Please watch

[AATW]

To be fair to Cody , like all of us , I don't think we are told of Joules experiment at school , college or university ( I certainly wasn't ) and here he is confirming that law of free gas expansion into a vacuum, It's a fine experiment carried out without any tricks. Please watch

I don't think anyone is disputing Joule's result. What iCare has done is explained why that result doesn't apply to a rocket.
And rockets have a chamber in which combustion occurs. That's where the pressure is and that is where the combustion occurs, the explosive power from that then forces the gas out of the end. Conservation of momentum does the rest.

[iCare]

Once he completes his experiments it's quite a revelation that he mentions the fire triangle , was it iCare  that brought that up? He concludes that it should be a fire square , the fourth requirement being pressure .

It's quite fascinating how you keep asking for precise scientific logic, when faced with a rebuttal.
While on the other hand you accept any superficial line of argument at face value when it suits yourself.

I brought up the fire triangle and that stands unrebutted.
"Pressure" is not required, but obviously all three aspects of the triangle need to be combined (pressure helps with that, but is not required).
Usually that is not a problem, but in low enough pressure - especially wenn trying to ignite something by heating the surface -

• the oxygen provided by the oxygen will obviously move away from the fuel/oxidizer => it's not available for sustaining the reaction.
• the heat generated will - at last partially - be directed away from the fuel => it's not available for sustaining the reaction

This is also in line with my previous "educated guess" (guess, because I don't know the exact setup of the experiment, not because I have doubts about the science involved):

Another plausible explanation would be, that due to the vacuum the igniter (which was obviously makeshift) didn't produce enough (concentrated) heat to start the reaction.
In this case, sealing the rocket thereby "focusing the heat" would have worked just as well if done in a vacuum.   

If you had paid more attention, you might have noticed, that Cody himself points out that "it was difficult, but not impossible" to start a chemical reaction in a vacuum.
And this is with regular materials; with specialized rocket fuel it is far easier. It is designed so all three aspects of the fire triangle will "stay together".

On top of this, pressure does not preclude a vacuum. "Press" any material against the rocket fuel ... there's pressure, no atmosphere needed.

So your interpretation of the video is not only wrong one way, but actually two ways.

To be fair to Cody , like all of us , I don't think we are told of Joules experiment at school , college or university ( I certainly wasn't ) and here he is confirming that law of free gas expansion into a vacuum, It's a fine experiment carried out without any tricks. Please watch

I watched and it has absolutely nothing to do with Joule's experiment .

And I stand corrected ... your interpretation of the video is wrong three ways.

iC

[iCare]

Rockets are about fuel undergoing a chemical reaction, resulting in (lots of) heat, gas and whatever other byproducts.
Energy stored in fuel => chemical reaction => lots of gas (and heat) produced => increased pressure  within rocket motor => physical reaction => gas gets "pushed" out into vacuum => physical reaction => rocket gets

iCare .This is your logical reasoning I presume. The first four steps steps apply to how a rocket engine functions in a pressured environment e.g. our air

The first four steps apply to how a rocket engine works in any environment.
See my other post.   

However in the vacuum of space :

If ( and that's a big one)you could start the control burn of fuel ( chemical reaction) in a vacuum you could produce heat .

It's not a big one. Cody has done it in the video you linked to, explicitly saying so himself at 11:20.

You could not produce pressure since the rocket chamber is open to the vacuum of space . This is where your logic fails . The rocket engine (not a motor ) is unable to produce a force since there is nothing to resist the free expansion of hot gas into the vacuum - Joules law , hence no reactive force .Your logic fails .

This is where my logic is spot on.
Gas (which has a mass greater than 0) accelerates out of the rocket. That can be easily be observed; if it wouldn't accelerate, it would stay in the rocket.
Hence another mass (the rocket) needs to accelerate in the opposite direction.

No resistance is needed, it is simply action-reaction.

For the n-th time:
Joule's law does not apply.
Joule's law also does not say, that there are no forces. It states that no work is done, int the sense that the energy contained in the gas does not change.
Either provide a valid reason why Joule's law would apply in the case of rockets or accept that it doesn't.

iC

[iCare]

Well, setting aside the byplay (which involved several challenges to your claims), your main argument was that rockets do not work in a vacuum because of free expansion / Joule expansion.
I have challenged and rebutted that argument.
It is insufficient as it does not apply; the "key requirements for free expansion are not met.
Ball's in your court ...

And the videos posted by those in agreement with your position absolutely destroy your rebuttal.

Let me reiterate: The  key requirements for free expansion are not met" by these experiemts.
They do not repaet the Joule's experiment.
Joule's experiment begins with gas under some pressure P at some temperature T, confined to one half of a thermally isolated container ..."
In those videos (and in rocket engines) there no thermally isolated container with gas being confined to one half.
=> Joule expansion does not apply in this case.

My rebuttal stands totally unimpressed and unharmed by these videos.

AATW now disagrees with you, as he admits these videos display rockets in operation in an environment that is NOT a vacuum.
The reason: Even he realizes that rockets cannot work in a vacuum.

First of all, by his own words, AATW does not disagree with me, so please do not make such assumptions or insinuate he has changed his mind when he hasn't.

Secondly, if there is no true vacuum in these videos (wich is true, but irrelevant), this cannot show that rockets will not work in a vacuum as there is no vacuum to show it in.
It simply shows that they are working in a near vacuum.
Which does give some indication, that they will work in a true vacuum as well.

iC

[somerled]

He demonstrates Joules law , not carries out his experiment. Word salad iCare.

Same guy , realises he's proved rocket engines won't work in a vacuum so sets about attempting to prove they do - after several attempts gives up and seals his rocket exhaust in air pressure turning it into a bomb .



FYI AATW rocket chambers are not sealed containers.

Hard to bear when science shows rockets do not work in a vacuum.

[iCare]

He demonstrates Joules law , not carries out his experiment.

As per your own request for scientific definitions, Joule's law has defined scientific requirements to be applicable.
To demonstrate Joule's law he would have to have a setup, that complies with the the requirements of Joule's law.
One of these requirements is a fixed amount of gas - that requirement is not met, so whatever he demonstrates, it's not Joule's law.

Word salad iCare.

Coming back your own request for scientific definitions: Using derogatives - especially without substantiating facts or reasoning - is not scientific, it's pathetic.

Same guy , realises he's proved rocket engines won't work in a vacuum so sets about attempting to prove they do - after several attempts gives up and seals his rocket exhaust in air pressure turning it into a bomb .

At 05:20 he says "This is not designed to work in a vacuum but at sea level".
If you keep listening he will explain why, which does comply to my previous line of argument and does make sense.
So if you want to use this video as proof, it proves my case not yours.
 
There is no need to use highly specialized (much more powerful and likely dangerous for home use) rocket fuel for rockets not intended to be used in a vacuum.
Also, he doesn't turn it into a bomb. It does not explode, it works as a rocket should.
The seal really just aids the reaction along while it's still starting up until it becomes self-sustaining.
Similar to old "times" when you needed a manually operated choke valve to start a cold engine.

Hard to bear when science shows rockets do not work in a vacuum.

I couldn't say, as it doesn't. Quite the opposite.

iC

[totallackey]

Well, setting aside the byplay (which involved several challenges to your claims), your main argument was that rockets do not work in a vacuum because of free expansion / Joule expansion.
I have challenged and rebutted that argument.
It is insufficient as it does not apply; the "key requirements for free expansion are not met.
Ball's in your court ...

And the videos posted by those in agreement with your position absolutely destroy your rebuttal.

Let me reiterate: The  key requirements for free expansion are not met" by these experiemts.
They do not repaet the Joule's experiment.
Joule's experiment begins with gas under some pressure P at some temperature T, confined to one half of a thermally isolated container ..."
In those videos (and in rocket engines) there no thermally isolated container with gas being confined to one half.
=> Joule expansion does not apply in this case.

My rebuttal stands totally unimpressed and unharmed by these videos.

AATW now disagrees with you, as he admits these videos display rockets in operation in an environment that is NOT a vacuum.
The reason: Even he realizes that rockets cannot work in a vacuum.

First of all, by his own words, AATW does not disagree with me, so please do not make such assumptions or insinuate he has changed his mind when he hasn't.

Secondly, if there is no true vacuum in these videos (wich is true, but irrelevant), this cannot show that rockets will not work in a vacuum as there is no vacuum to show it in.
It simply shows that they are working in a near vacuum.
Which does give some indication, that they will work in a true vacuum as well.

iC

So, you too, admit there is no vacuum in these videos.

The mental reservation and equivocation exhibited in your writing today is quite astounding.

[thors_evil_twin]

The mental reservation and equivocation exhibited in your writing today is quite astounding.

We seam to be arguing semantics. So I have pulled up a definition that we should all be able to agree to, and I believe that from Merriam Webster the definition that is applicable here is the second one, and as such there is a fair bit of wiggle room on how to define it. I would argue that 2a is logically false, how could any thing be "absolutely devoid of matter".

Definition of vacuum (from, Merriam Webster)
1 : emptiness of space
2   a : a space absolutely devoid of matter
   b : a space partially exhausted (as to the highest degree possible) by artificial means (such as an air pump)
   c : a degree of rarefaction below atmospheric pressure
3   a : a state or condition resembling a vacuum : void the power vacuum in Indochina after the departure of the French— Norman Cousins
   b : a state of isolation from outside influences people who live in a vacuum … so that the world outside them is of no moment— W. S. Maugham

[iCare]

Secondly, if there is no true vacuum in these videos (wich is true, but irrelevant), this cannot show that rockets will not work in a vacuum as there is no vacuum to show it in.
It simply shows that they are working in a near vacuum.
Which does give some indication, that they will work in a true vacuum as well.

So, you too, admit there is no vacuum in these videos.

I never said there was a vacuum in those videos. (If I wrote something giving that impression, please point me to it, so I can clarify.)
I know it is sometimes hard to keep track with several people cross-posting, but I am the guy who tries to stick with facts, deduction, logic and common sense; my line of reasoning is neither based on nor dependent on videos .
I do comment on videos when I get pulled into a video discussion.

True vacuum is pretty hard to create and I wouldn't expect it in some enthusiast experiment as referenced in this thread.
So, admittedly, I should have written "which is probably true" as I do not have any first hand information to be sure.
Doesn't, however, change the point made:
If there is no vacuum in those videos they do not prove anything in regards to what happens (or doesn't happen) in a vacuum.

The mental reservation and equivocation exhibited in your writing today is quite astounding.

This is actually turning into a entertaining discussion ... somerled resorts to derogatives when running out of arguments, you obviously go the other way pulling out the fancy words?

I have openly stated facts and deducted conclusions in a logically sound manner - openly explaining my line of thought in detail.
Please point out where you suspect "mental reservation".

I try to phrase my posts as unambiguously and concise as possible. I do not always fully meet that goal, but I'll happily disambiguate if need be.
So where do you see any equivocation?

Once again:
If you make a claim, please support it in an appropriate way, so the reader (me or whoever) does not have to second-guess you (you wouldn't want to create the impression of mental reservation, would you?) and can respond without having to ask for clarification.

Finally, as always:
Do you have any sound explanation why Joule expansion, which explicitly requires thermal insulation (to prevent a change of temperature of the gas) could apply to rockets, where the chemical reaction creates a drastic increase in temperature.
(Note: This is, as repeatedly stated, only one of the requirements, that are not met.)

iC

[Tumeni]

Can I propose a different approach?

Conventional wisdom holds that there are at least two craft orbiting the Moon, actively sending signals back to Earth.

One is the Lunar Reconnaissance Orbiter, the other the Chinese relay satellite picking up signals from their rover on the far side, and relaying them to Earth. There may be more, I've just picked the obvious, prominent examples.

It strikes me that all that need be done is point an antenna at the Moon, find the right frequency/frequencies, and the presence of any systematic transmission is proof that rockets work in space. Else, how would the craft sending the signals have got there?

[somerled]

It is clear that rocket engines cannot work in a vacuum or even a low pressure environment . You can change you rocket into a bomb but then that's a different experiment .

Mr Cody's trying to achieve ignition of rocket fuel in his vacuum chamber experiment raised the pressure by an unspecified amount and still failed .

Would be interesting to have seen at what pressure ignition would occur .  Him being an intelligent diligent researcher would have done this I believe . Perhaps he could share this info if so .

No amount of waffle can hide the fact that rockets obey the predictions of the laws of physics and as such fail to function under vacuum/low pressure conditions .

[Tumeni]

No amount of waffle can hide the fact that rockets obey the predictions of the laws of physics and as such fail to function under vacuum/low pressure conditions .

Yet we have evidence of craft in orbit around our Moon. The Space Geodesy Facility in the UK spent five years laser-ranging the LRO. How did they get there, if the above is true?

https://www.sciencedirect.com/science/article/abs/pii/S0019103516303657?via%3Dihub

[Tumeni]

You can change you rocket into a bomb but then that's a different experiment

What do you see as the difference?

I see it as -

Bomb - fixed supply of explosive/propellant, so instantaneous ignition/combustion/explosion

Rocket - regulated supply of explosive/propellant, so consistent ignition/combustion/explosion whilst explosive/propellant being supplied

In practical terms, do you see any differences pertinent to this discussion that precludes one or the other working in vacuum?

[iCare]

It is clear that rocket engines cannot work in a vacuum or even a low pressure environment .

No, it is not clear - that is why we are discussing it instead of agreeing with one another

Mr Cody's trying to achieve ignition of rocket fuel in his vacuum chamber experiment raised the pressure by an unspecified amount and still failed .

As already pointed out, he did not fail and he explains why there were issues and that they were explicitly not because rocket engines cannot work in a vacuum.
His conclusion is the exact opposite, at 7:17 he states "rocket motors can produce just as much thrust in a vacuum if not a little more".

Him being an intelligent diligent researcher would have done this I believe . Perhaps he could share this info if so .

So as you accept Cody as an intelligent diligent researcher, do you accept the result of his research, that "Rockets do work in a vacuum"?

No amount of waffle can hide the fact that rockets obey the predictions of the laws of physics and as such fail to function under vacuum/low pressure conditions .

As I have provided detailed logical deduction based on the laws of physics and chemistry, I guess the "waffling" is not directed at me.
However, you keep dodging my questions and and deflecting to videos that don't even show/tell what you claim to see in them.
No amount of you ignoring counterarguments, reasonable doubt and repeating unsupported claims will make those faulty claims less faulty.

As to you everything is clear - which law of physics predicts that rockets can't work in a vacuum?
And which law of chemistry predicts, that a chemical reaction will not take place in a vacuum?

iC

[somerled]

Newtons first second and third laws . Joules law of free expansion of gas into a vacuum . No work is done therefore no force therefore no reaction therefore no acceleration .

         You do not understand the principles behind these laws - these laws are not open to debate . They dictate the inability of a rocket engine to produce any force in a vacuum . All amply demonstrated in the videos where experimenters cannot even ignite rocket fuel in a vacuum  .

         You seem to be unable to differentiate between a rocket engine and a bomb .
You have yet to state where the reactive force of thrust is produced or shown any logical argument which conforms to these laws that allows for rocket engines to produce thrust in a vacuum.
You have ignored the fact that these video experimenters state that pressure is required to produce a chemical reaction of rocket fuel in a vacuum and have to change their rocket engines into pressurised bombs .

You have however , excelled in your sophistry.

[iCare]

Newtons first second and third laws .

Newton's Laws do not prevent rockets from functioning in a vacuum, they require them to function.
As explained before when one mass is accelerated one way, another mass moves must be accelerated the opposite way.
This is a basic law and it is easily observable that gas (which as a mass) is leaving the rocket; to do that it must accelerate.
If you wan't a rocket to fail in a vacumm you must dispute Newton's laws.

Joules law of free expansion of gas into a vacuum . No work is done therefore no force therefore no reaction therefore no acceleration .

Again, as explained before:

• No work is not the same as no force applied. If you hold a weight stationary with your arm extended (for fun, imagine a mug of beer), no work is done, as the object doesn't move; however upward and downward forces are applied - in this case they cancel each other out.
• Joule's law of free expansion does not apply, because it describes a completely different process.

 

You do not understand the principles behind these laws - these laws are not open to debate .

As repeatedly state, I do not question those laws.
Despite your constant (and unproven) claim to the contrary, however, I do understand the principles behind those laws.
That is why I feel the need to comment on your faulty application of these laws, which lead you to wrong conclusions.

They dictate the inability of a rocket engine to produce any force in a vacuum .

See above. They do not, quite the opposite.

All amply demonstrated in the videos where experimenters cannot even ignite rocket fuel in a vacuum .

The problem of igniting the fuel is a separate (chemical) one and the videos have shown, that it is possible.
The videos have also shown, that rockets work in a near vacuum. They would also show them working in a total vacuum.
That's hard to do in an experiment, luckily satellites in orbit (controlling their orbit with thrusters) prove that what Newton's Law describes is also working in reality.

You seem to be unable to differentiate between a rocket engine and a bomb.

For the sake of "starting a chemical reaction in a vacuum" I think it really doesn't matter that much.
Blocking the exhaust temporarily as in the videos does not turn a rocket into a bomb.
If you'd really block the exhaust, e.g. welding it shut, that would likely turn it into a bomb.
So again ... it is you who is unable to correctly apply definitions.

You have however , excelled in your sophistry.

Thank you for the compliment, but I cannot accept it. While my reasoning is skillful, it is not deceptive.
Unfortunately I can't return it either. While your reasoning appears deceptive, it does not appear skillful to me.

iC
(Edited for typos and some phrasing.)