JEE Main 2021PhysicsKinetic Theory of GasesMediumNumerical

JEE Main 2021 — Kinetic Theory of Gases Question with Solution

JEE Main 2021 (24 Feb Shift 2)

Question

The root-mean-square speed of molecules of a given mass of a gas at 27 °C and 1 atmosphere pressure is 200 m s-1. The root-mean-square speed of molecules of the gas at 127 °C and 2 atmosphere pressure is x3 m s-1. The value of x will be __________.

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Show full solutionCorrect answer: 400
Correct answer
400

Step-by-step explanation

vrms=3RTM⇒vrms∝T⇒vrms2vrms1=T2 T1=400300=23

vrms2=23vrms1=23×200⇒vrms2=4003 m s-1.

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About this question

This is a previous-year question from JEE Main 2021, 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.