In the case of a rocket, the pressure in the reaction chamber increases (due to gas and heat being produced bei the exothermic chemical reaction) => gas gets "thrown" out to "wherever".
You just admitted Joule's Law.
I have never doubted Joule's Law. I'm simply pointing out, that it does not apply to the way rockets work. Specifically it does not prevent them from working in a vacuum.
For the detailed explanation, see my previous posts.
When are you going to admit a rocket is a closed system, as depicted in the source I provided?
I have already answered that:
This source does not claim, that a rocket is a closed system.
It claims that "rocket + fuel" (to be more precise "rocket + fuel + exhaust") can be defined as a closed system as far as forces are concerned.
Clever definition of "systems" is a legitimate approach to make calculations or solving a problem easier.
As momentum does not care about volume/heat and the vacuum does not interact with mass and force, this would seem to be a valid assumption when looking at Newton's Laws.
I don't have an issue with the definition as depicted in the source you provided.
For calculating acceleration the assumption of a closed system as described seems to be a valid approach leading to the conclusion, that a rocket will work in a vacuum.
My problem was - and still is - that you are not specific about what
you define as "rocket"?
Is it the same as in the source (with/without fuel/exhaust/...?) and what conclusions you draw from that?
Do you agree that a jet engine and a rocket engine are essentially the same thing, performing the same functions, the exception being the rocket carries its own oxidizers, requiring no intakes?
This sounds like one of those directional/suggestive questions that try to (mis-)lead you on a specific path ... but let's see where you want to take us. Live's a journey.
It isn't as simple as that, but on a basic level I do agree.
Both are internal combustion engines; burning fuel to create heat and gas (and/or other products of the chemical reaction) thereby creating thrust from the chemical energy stored in the fuel.
Rockets generally require no intake (generally, as rockets can be air-augmented). On the other hand, let me point out, that the oxidizer is only part of why jet engines require an intake.
So the requirement of an intake is by far not the only and not necessarily the most signifikant difference between rockets and jet engines (as used e.g. for airplanes).
The details of the process are quite different for both.
iC