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Friday, 9 October

NEET UG 2026 · Physics · Question 2

NEET 2026 Physics, question 2

Question 2 of the NEET 2026 paper (re-exam) is a Physics question from Kinetic Theory. Its idea, Mean Free Path, was asked twice, in 2020 and 2026, across NEET 2017–2026. The NTA final answer key gives option 4.

Updated 2026-10-08

Q2 · Physics

The mean free path of molecules in an ideal gas A is half that of another ideal gas B. The diameter of the spherical molecules of gas A is twice the diameter of the molecules of B. If number densities of the gases A and B are nAn_A and nBn_B, respectively, then the correct option is :

  1. 1nA=nBn_A=n_B
  2. 2nA=2nBn_A=2n_B
  3. 3nA=14nBn_A=\frac{1}{4}n_B
  4. 4nA=12nBn_A=\frac{1}{2}n_BOfficial answer

Official answer: option 4 · NTA final answer key

Same idea

Mean Free Path, in other papers

NEET asked this idea twice, in 2020 and 2026. The other question below.

  • 2020 Q155The mean free path for a gas, with molecular diameter d and number density n can be expressed as :One-line MCQ · Medium

Mean Free Path: every question and how it was framed

The chapter

Kinetic Theory in ten years of NEET

14 questions from 2017–2026, asked in 10 of 10 papers, about 1.4 a paper. Kinetic Theory of Gases alone had 14.

Chapter analysisStudy this chapterPractise this chapter

Kinetic Theory: questions per paper

0241’171’181’193’201’211’221’231’242’252’26