JEE Main 2021 · PhysicsMultiple choiceSingle correctEasyRecall

JEE Main 18 March 2021, Shift 1, Physics Q17

Question 17 of 90 in this shift, Physics question 17 of 30, Section A.

What will be the average value of energy along one degree of freedom for an ideal gas in thermal equilibrium at a temperature T ? (

k_B

is Boltzmann constant)

(1) $k_BT$
(2) $\frac{1}{2}k_BT$ Official answer
(3) $\frac{3}{2}k_BT$
(4) $\frac{2}{3}k_BT$

Official answer

Option 2

NTA final key.

Chapter: Kinetic Theory
Topic: Kinetic Theory of Gases
Idea tested: Law of Equipartition

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Asked 3× 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 42 of the 174 JEE Main shifts held from 2017 to 2026.