JEE Main 2020PhysicsKinetic Theory of GasesEasyMCQ

JEE Main 2020 — Kinetic Theory of Gases Question with Solution

JEE Main 2020 (03 Sep Shift 1)

Question

Consider a gas of triatomic molecules. The molecules  are assumed to be triangular and made of massless rigid rods whose vertices are occupied by atoms. The internal energy of a mole of the gas at temperature T is:

Choose an option

Show full solutionCorrect option: D
Correct answer
D3RT

Step-by-step explanation

The formula of internal energy of a gas is given by

U=f2RT

Here R is the gas constant and T is temperature.

R=8.314 J mol-1 K-1

For the given configuration of triatomic molecules, the degree of freedom f=6

⇒ U=62RT=3RT

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About this question

This is a previous-year question from JEE Main 2020, covering the Kinetic Theory of Gases chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.