JEE Main 2021 · PhysicsNumerical answerNumerical valueMediumCalculation

JEE Main 25 February 2021, Shift 1, Physics Q21

Question 21 of 90 in this shift, Physics question 21 of 30, Section B.

A monoatomic gas of mass 4.0 u is kept in an insulated container. Container is moving with velocity 30 m/s. If container is suddenly stopped then change in temperature of the gas (R=gas constant) is

\frac{x}{3R}

. Value of

x

is __________.

Official answer

3600

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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9 Apr 2024, Shift 2 · Q41The temperature of a gas is $-78^\circ$ C and the average translational kinetic energy of its molecules is K. The temperature at which the…EasySingle correct
27 Jan 2024, Shift 1 · Q39The average kinetic energy of a monoatomic molecule is 0.414 eV at temperature : (Use $K_B = 1.38\times10^{-23}$ J/mol-K)EasySingle correct
31 Jan 2024, Shift 1 · Q39The parameter that remains the same for molecules of all gases at a given temperature is :EasySingle correct
8 Apr 2023, Shift 2 · Q33The temperature at which the kinetic energy of oxygen molecules becomes double than its value at $27^\circ$ C isEasySingle correct
15 Apr 2023, Shift 1 · Q32A flask contains Hydrogen and Argon in the ratio 2:1 by mass. The temperature of the mixture is 30°C. The ratio of average kinetic energy…EasySingle correct
25 Jul 2022, Shift 1 · Q38Following statements are given : (A) The average kinetic energy of a gas molecule decreases when the temperature is reduced. (B) The…EasyOther

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.