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A monoatomic ideal gas, initially at temperature T_1 is enclosed in a cylinder fitted with a frictionless piston. The gas is allowed to expand…

JEE Main 2021 — Physics Thermodynamics

2021mcqeasy

A monoatomic ideal gas, initially at temperature T1{T}_{1}T1​ is enclosed in a cylinder fitted with a frictionless piston. The gas is allowed to expand adiabatically to a temperature T2{T}_{2}T2​ by releasing the piston suddenly. If l1{l}_{1}l1​ and l2{l}_{2}l2​ are the lengths of the gas column, before and after the expansion respectively, then the value of T1T2\frac{{T}_{1}}{{T}_{2}}T2​T1​​ will be:

Official previous-year question

Held on 25 Jul 2021 · Verified 6 Jul 2026.

Options

  1. A

    (l1l2)23{(\frac{{l}_{1}}{{l}_{2}})}^{\frac{2}{3}}(l2​l1​​)32​

  2. B

    (l2l1)23{(\frac{{l}_{2}}{{l}_{1}})}^{\frac{2}{3}}(l1​l2​​)32​

  3. C

    (l2l1)(\frac{{l}_{2}}{{l}_{1}})(l1​l2​​)

  4. D

    l1l2\frac{{l}_{1}}{{l}_{2}}l2​l1​​

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