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An ideal gas in a cylinder is separated by a piston in such a way that the entropy of one part is S_1 and that of the other part is S_2. Given that…

JEE Main 2021 — Physics Thermodynamics

2021mcqmedium

An ideal gas in a cylinder is separated by a piston in such a way that the entropy of one part is S1{S}_{1}S1​ and that of the other part is S2{S}_{2}S2​. Given that S1>S2{S}_{1}>{S}_{2}S1​>S2​. If the piston is removed then the total entropy of the system will be:

Official previous-year question

Held on 18 Mar 2021 · Verified 6 Jul 2026.

Options

  1. A

    S1×S2{S}_{1}\times {S}_{2}S1​×S2​

  2. B

    S1−S2{S}_{1}-{S}_{2}S1​−S2​

  3. C

    S1S2\frac{{S}_{1}}{{S}_{2}}S2​S1​​

  4. D

    S1+S2{S}_{1}+{S}_{2}S1​+S2​

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