One mole of an ideal diatomic gas undergoes a transition from A to B along a path AB as shown in the figure.
The change in internal energy of the gas during the transition is :
-20 kJ
20 J
-12 kJ
20 kJ
∆U=nCV∆T and T=PVnR So ∆T=T2-T1=P2V2-P1V1nR So ∆U=nRγ-1P2V2-P1V1nR=P2V2-P1V1γ-1 ⇒ ∆U=-8×1032/5=-20 kJ