All Problems

First law of thermodynamics, heat capacity

Problem 2.26

Demonstrate that the interval energy \(U\) of the air in a room is independent of temperature provided the outside pressure \(p\) is constant. Calculate \(U,\) if \(p\) is equal to the normal atmospheric pressure and the room's volume is equal to \(V=40 \mathrm{~m}^{3}\).

Reveal Answer
U=pV/(γ1)=10MJU=p V /(\gamma-1)=10 \mathrm{MJ}