# Search results

1. ### Question about fluid expansion

Thank you, you are very helpful I wish I could somehow give you a thumbs up or something :)
2. ### Question about fluid expansion

Thanks a lot for the answer, that's exactly what I wanted, could you please tell me how much this temperature change is in one cycle is it a small amount and needs to be repeated or can it be large with the right substance? And also, the inversion temperature must be above room temperature in...
3. ### Question about fluid expansion

Hi, When a hot and dense fluid suddenly expands, how much can it cool down. Lets take for example an expansion valve from an AC, does the fluid do work when passing through the valve or does it not even need to do work in order to cool down. What is the lowest temperature that the fluid can...
4. ### Principle of least action?

great, thanks a lot on that info that's exactly what I needed. Susskind is a funny guy :)
5. ### Principle of least action?

hehe I bet he did but I think that Lagrange did most of the important work on this subject.
6. ### Principle of least action?

hi, please if somebody could explain why anybody would consider the "action" and is there any proof that the minimal action actually gives the correct route of a problem?