A sample of ideal gas is subjected to two distinct cyclic processes on a PV diagram, each starting and ending at the same state S.
• Cycle 1 is a clockwise triangular loop whose vertices are S(P0,V0), E(2P0,V0), and F(P0,2V0).
• Cycle 2 is a counter-clockwise rectangular loop whose corners are S(P0,V0), G(3P0,V0), H(3P0,2V0), and J(P0,2V0).
Assume quasi-static processes along all edges and take expansion work done by the gas as positive.
(a) For each cycle, state whether the net work done by the gas is positive, negative, or zero. Explain how the direction of traversal on the PV diagram determines the sign.
(b) Compare the magnitudes of the net work done by the gas in Cycle 1 and Cycle 2. Provide a reasoned argument based solely on the areas enclosed by the two loops.
(c) Suppose both cycles are executed once in succession, starting and ending at state S. Determine the algebraic sum of the net work done by the gas over the combined two-cycle process and justify your answer.