JEE Main 2022 · PhysicsMultiple choiceSingle correctMediumMulti-step

JEE Main 26 June 2022, Shift 1, Physics Q39

Question 39 of 90 in this shift, Physics question 9 of 30, Section A.

A thermally insulated vessel contains an ideal gas of molecular mass M and ratio of specific heats 1.4. Vessel is moving with speed

v

and is suddenly brought to rest. Assuming no heat is lost to the surrounding and vessel temperature of the gas increases by : (R=universal gas constant)

(1) $\frac{Mv^2}{7R}$
(2) $\frac{M\,v^2}{5\,R}$ Official answer
(3) $2\,\frac{M\,v^2}{7\,R}$
(4) $7\,\frac{M\,v^2}{5\,R}$

Official answer

Option 2

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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17 Mar 2021, Shift 1 · Q8A polyatomic ideal gas has 24 vibrational modes. What is the value of $\gamma$ ?MediumSingle correct
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3 Sep 2020, Shift 2 · Q8To raise the temperature of a certain mass of gas by $50^\circ$ C at a constant pressure, 160 calories of heat is required. When the same…MediumSingle correct
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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.