Question

Consider an ideal gas at a given state expanded in two different ways to a fixed final volume. In the first case, the gas is expanded at constant pressure, and in the second case at constant temperature. Sketch each process on a P-v diagram. For which case is the work done greater?

Answer 1

Area under P-v diagram represents work done for a closed system

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FYI

Process 1:- Constant temperature expansion process

Process 2:- Constant pressure or Isobaric expansion process

Process 3:- Adiabatic expansion process

By observing P-v diagram we can conclude that

Area under process 2 > Area under process 1 >Area under process 3

Hence, Work by process 2 > Work by process 1> Work by process 3.

Work under constant pressure expansion process is maximum.

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