How would I show that during quastatic isothermal expansion of a monatomic ideal gas, the change in entropy is related to the heat input Q by the simple formula: delta S=Q/T(adsbygoogle = window.adsbygoogle || []).push({});

Show that it is not valid for the free expansion process described.

Answer: Putting heat into a system always increases its entrophy.

deltaS=Nk lnVf/Vi (U,N fixed).

Ireally don't know how to do this. Can someone explain?

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# Quasistatic isothermal expansion

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