If one mole of an ideal gas at (P1,V1) is allowed to expand reversibly and isothermally (A to B) its pressure is reduced to one-half of the original pressure (see figure). This is followed by a constant volume cooling till its pressure is reduced to one-fourth of the initial value (B→C). Then it is restored to its initial state by a reversible adiabatic compression (C to A). The net workdone by the gas is equal to:
Held on 24 Feb 2021 · Verified 6 Jul 2026.
0
RTln(2)
−2(γ−1)RT
RT[ln(2)−2(γ−1)1]
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