JEE Main 2021 · PhysicsMultiple choiceSingle correctEasyCalculation

JEE Main 16 March 2021, Shift 2, Physics Q7

Question 7 of 90 in this shift, Physics question 7 of 30, Section A.

Calculate the value of mean free path (

\lambda

) for oxygen molecules at temperature

27^\circ\mathrm{C}

and pressure

1.01\times10^5

Pa. Assume the molecular diameter 0.3 nm and the gas is ideal. (

k=1.38\times10^{-23}\ \mathrm{JK^{-1}}

)

(1)32 nm
(2)58 nm
(3)86 nm
(4)102 nmOfficial answer

Official answer

Option 4

NTA final key.

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

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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.