Physics · 2021
JEE Main · 24 February 2021, Shift 2 · Q5
If one mole of an ideal gas at ( P_1, V_1) is allowed to expand reversibly and isothermally (A to B) its pressure is reduced to one-half of the…
If one mole of an ideal gas at $\displaystyle \left(\mathrm{P}_1, \mathrm{~V}_1\right)$ 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 :
Official answer
(1)
$\displaystyle \operatorname{RT}\left(\ln 2-\frac{1}{2(\gamma-1)}\right)$
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.