A thermodynamic system undergoes a cyclic process consisting of two isobaric and two isothermal transformations. Which of the following statements correctly describes the net work done and change in internal energy over one complete cycle?

💡 Solution & Explanation

Internal energy is a state function, meaning its value depends solely on the current state of the system and not on the path taken. Over any complete thermodynamic cycle, the system returns to its initial state, resulting in a net internal energy change of zero. By the first law of thermodynamics, the net heat supplied in a cycle must therefore equal the net mechanical work done by the system on its surroundings.