JEE Main 2021 · PhysicsMultiple choiceSingle correctEasyApplication

JEE Main 25 February 2021, Shift 1, Physics Q18

Question 18 of 90 in this shift, Physics question 18 of 30, Section A.

A diatomic gas, having

C_P=\frac{7}{2}R

and

C_V=\frac{5}{2}R

, is heated at constant pressure. The ratio dU : dQ : dW :

(1)5 : 7 : 2Official answer
(2)3 : 7 : 2
(3)3 : 5 : 2
(4)5 : 7 : 3

Official answer

Option 1

NTA final key.

Chapter: Thermodynamics
Topic: First Law of Thermodynamics
Idea tested: Heat in Isochoric and Isobaric Processes

Same idea in other shifts

Asked 5× 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.