A thermodynamic process is shown in Fig. The pressures and volumes corresponding to some points in
the figure are,. In process AB, 600 J of heat and in process BC, 200 J of heat is added to the system. The change in the internal energy in process AC would be
560 J
800 J
600 J
640 J
Process AB is isochoric, i.e. the volume remains constant. Thus ?V = 0. Hence work
done P?V = 0. Process BC is isobaric, i.e. the pressure remains constant and external
work has to be done. The work done = Therefore, change in internal energy is