Question

Figure shows the P-V diagram of an ideal gas undergoing a change of state from A to B. Four different parts I, II, III and IV as shown in the figure may lead to the same change of state.

1. Change in internal energy is same in IV and III cases, but not in I and II.
2. Change in internal energy is same in all the four cases.
3. Work done is maximum in case I
4. Work done is minimum in case II.

Answer 1

b and c

Explanation:

Change in internal energy depends only upon the initial and final positions and not on the path followed. Hence, the change in internal energy is the same for all the cases. The work done is dependent upon the path followed. Work done is the area enclosed by the path with the x-axis. Since path I enclose the maximum area with the x-axis, the work done is maximum in case I.