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Number of molecules in a volume of 4 cm^3 of a perfect monoatomic gas at some temperature T and at a pressure of 2 cm of mercury is close to? (Given,…

JEE Main 2020 — Physics Thermodynamics

2020mcqeasy

Number of molecules in a volume of 4cm34{\mathrm{cm}}^{3}4cm3 of a perfect monoatomic gas at some temperature T and at a pressure of 2cm2\mathrm{cm}2cm of mercury is close to? (Given, mean kinetic energy of a molecule (at T) is 4×10−14erg,g=980cms−24\times {10}^{-14}\mathrm{erg},g=980\mathrm{cm}{s}^{-2}4×10−14erg,g=980cms−2 density of mercury =13.6gcm−3=13.6g{\mathrm{cm}}^{-3}=13.6gcm−3)

Official previous-year question

Held on 5 Sept 2020 · Verified 6 Jul 2026.

Options

  1. A

    4.8×10184.8\times {10}^{18}4.8×1018

  2. B

    4.0×10164.0\times {10}^{16}4.0×1016

  3. C

    5.8×10165.8\times {10}^{16}5.8×1016

  4. D

    5.8×10185.8\times {10}^{18}5.8×1018

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