Question

In any cyclic process, the internal energy of any gas

(A) increases

(B) decreases

(C) becomes zero

(D) remains constant

Answer 1

Correct option is (D) remains constant

Internal energy is a state function. In a cyclic process the system returns to its initial state and so the internal energy is not changed. The heat added to the system equals the work done by the system. A free expansion is an adiabatic change that does no work.