JEE Main 2021 · PhysicsMultiple choiceSingle correctMediumCalculation

JEE Main 17 March 2021, Shift 1, Physics Q8

Question 8 of 90 in this shift, Physics question 8 of 30, Section A.

A polyatomic ideal gas has 24 vibrational modes. What is the value of

\gamma

(1)10.3
(2)1.30
(3)1.03Official answer
(4)1.37

Official answer

Option 3

NTA final key.

Chapter: Kinetic Theory
Topic: Kinetic Theory of Gases
Idea tested: Gamma and Degrees of Freedom

Same idea in other shifts

Asked 9× in all

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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 108 of the 174 JEE Main shifts held from 2017 to 2026.