Is there a clear analogy here between volume and entropy? Looking at: (dQ)/T=dS, (dW)/P=dV

Bernard Boyer 2022-07-20 Answered
Is there a clear analogy here between volume and entropy? Looking at: d Q T = d S , d W P = d V
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Answers (1)

minotaurafe
Answered 2022-07-21 Author has 22 answers
The general expression for the first law (using the OP sign convention) is: d E = δ q + δ w. When the process is reversible it is possible to write: d E = T d S + P d V. This expression is the diferential of a function E(S,V):
d E = E S d S + E V d V
The similarity between V and S in the expression is that both are independent functions of the internal energy, while temperature and pressure are partial derivatives:
T = E S
P = E V
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