JEE Main 2025 · PhysicsMultiple choiceSingle correctEasyConceptual

JEE Main 7 April 2025, Shift 2, Physics Q33

Question 33 of 75 in this shift, Physics question 8 of 25, Section A.

The helium and argon are put in the flask at the same room temperature (300 K). The ratio of average kinetic energies (per molecule) of helium and argon is : (Give : Molar mass of helium = 4 g/mol, Molar mass of argon = 40 g/mol)

(1) $1:1$ Official answer
(2) $1:10$
(3) $10:1$
(4) $1:\sqrt{10}$

Official answer

Option 1

NTA final key.

Chapter: Kinetic Theory
Topic: Kinetic Theory of Gases
Idea tested: Kinetic Energy and Temp

Same idea in other shifts

Asked 11× 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.