Question

In , consider the closed loop 1→2→3→4→1. This is a cyclic process in which the initial and final states are the same. Take the graduation p0 = 2.0 atm and the graduation V0 = 1.0 L .

Part A

Find the total work done by the system in this process, and show that it is equal to the area enclosed by the loop.

Part B

How is the work done during the process in Part A related to the work done if the loop is traversed in the opposite direction, 1→4→3→2→1?

Express your answer in joules to two significant figures.

Answer 1

Part A

Work done for processes 2-->3 and 4 -->1 is zero

Work done for process 1 --> 2 = p₁ (V₂ - V₁) = 10 * 1.013e5 (8 - 2 )e-3

Work done for process 1 --> 2 = 10 * 1.013e5 * 6e-3

Work done for process 1 --> 2 = 6078 J

Now,

Work done for process 3 ---> 4 = -2 * 1.013e5 * 6e-3

Work done for process 3 ---> 4 = -1215.6 J

so,

total work done = 4862.4 J

Now , To prove that it is equal to the area enclosed by the loop.

W = (6e-3) * (8*1.013e5)

W = 4862.4 J

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Part B

If the loop is traversed in the opposite direction,

W = -4862.4 J