JEE Main 2023 · PhysicsMultiple choiceSingle correctMediumCalculation

JEE Main 13 April 2023, Shift 2, Physics Q39

Question 39 of 90 in this shift, Physics question 9 of 30, Section A.

The mean free path of molecules of a certain gas at STP is

1500d

, where

d

is the diameter of the gas molecules. While maintaining the standard pressure, the mean free path of the molecules at 373K is approximately:

(1) $1500d$
(2) $750d$
(3) $2049d$ Official answer
(4) $1098d$

Official answer

Option 3

NTA final key.

Chapter: Kinetic Theory
Topic: Kinetic Theory of Gases
Idea tested: Mean Free Path Temperature Dependence

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.