question_answer 19)

                  Figure shown the P-V diagram of an ideal gas undergoing a change of state from A to B. Four different part I, II, III and IV as shown in the figure may lead to the same change of state. (a) Change in internal energy is same in IV and III case, but not in I and II. (b) Change in internal energy is same in all the four cases. (c) Work done is maximum in case I (d) Work done is minimum in case II                

Answer:

                  (b, c) Internal energy of a system is the function of the state of the system. Work done = Area under P-V diagram.