Kinetic Theory and Thermodynamics: Mean Free Path MCQ

Solve this quality-checked JEE multiple-choice question, then review the correct answer and explanation.

Timer-based practiceDetailed answer reviewMobile-friendly flow

Mean Free PathHardQuestion 31017

Question

Mean free path of air at room temperature is of the order:

A
1 cm
B
1 mm
C
100 nm
Correct
D
10 μm

Correct answer

100 nm

Explanation

Mean free path of air molecules at atmospheric pressure is ~70 nm ≈ 100 nm. This is much smaller than everyday length scales but large compared to molecular size.

Review Kinetic Theory and Thermodynamics notes Start timed chapter practice