JEE Main 2025 · PhysicsMultiple choiceSingle correctEasyCalculation

JEE Main 8 April 2025, Shift 2, Physics Q33

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

A monoatomic gas having

\gamma = \frac{5}{3}

is stored in a thermally insulated container and the gas is suddenly compressed to

\left(\frac{1}{8}\right)^{th}

of its initial volume. The ratio of final pressure and initial pressure is: (

\gamma

is the ratio of specific heats of the gas at constant pressure and at constant volume)

(1)32Official answer
(2)16
(3)40
(4)28

Official answer

Option 1

NTA final key.

Chapter: Thermodynamics
Topic: Thermodynamic Processes
Idea tested: Adiabatic Process Analysis

Same idea in other shifts

Asked 8× in all

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18 Mar 2021, Shift 1 · Q4The P-V diagram of a diatomic ideal gas system going under cyclic process as shown in figure. The work done during an adiabatic process CD…MediumSingle correctHas a figure

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.