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1. ### Deegres of fredom in thermodynamics

In thermodynamics heat reservoir has a lot deegres of freedom. Can you tell me some examples of that deegres. Thx
2. ### Thermodynamics question

This \delta-s from my posts are variations, not derivatives.
3. ### Thermodynamics question

You can't use eq \delta U=T\delta S-P\delta V Second law of thermodynamics is defined by eq d U=TdS-Pd V You can't simply change derivatives with variations. Give reference for that.
4. ### Thermodynamics question

Also is interesting that Landau then says \frac{\partial^2 U}{\partial S^2}(\delta S)^2+2\frac{\partial^2 U}{\partial S\partial V}\delta S\delta V+\frac{\partial^2 U}{\partial V^2}(\delta V)^2>0 If such an inequality holds for arbitrary \delta S and \delta V then \frac{\partial^2 U}{\partial...
5. ### Thermodynamics question

Yes you're right. Landau says in his book. In thermodynamics equlibrium G is minimum. Thus for any small deviation from equilibrium the change of the quontity G musy be positive. So \delta U -T\delta S+P\delta V>0 In other words the minimum work which must be done from bring this part of...
6. ### Thermodynamics question

Tnx. I fixed it. Do you know answer to my question?
7. ### Thermodynamics question

If in some thermodynamics system preasure P and temperature T are constant then Gibbs potential has minimum. G=U-TS+PV Variation of G is \delta G=\delta U-T \delta S+P \delta V U=U(S,V) \delta U=(\frac{\partial U}{\partial S})_V\delta S+(\frac{\partial U}{\partial V})_S\delta...