JEE Main 2020 · PhysicsMultiple choiceSingle correctMediumMulti-step

JEE Main 3 September 2020, Shift 2, Physics Q8

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

To 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 mass of gas is cooled by

100^\circ

C at constant volume, 240 calories of heat is released. How many degrees of freedom does each molecule of this gas have (assume gas to be ideal) ?

(1)3
(2)5
(3)6Official answer
(4)7

Official answer

Option 3

NTA final key (Sep 2020).

Chapter: Thermodynamics
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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26 Jul 2022, Shift 2 · Q42A gas has $n$ degrees of freedom. The ratio of specific heat of gas at constant volume to the specific heat of gas at constant pressure…EasySingle correct
25 Jun 2022, Shift 2 · Q36The ratio of specific heats $\left(\frac{C_P}{C_V}\right)$ in terms of degree of freedom ( $f$ ) is given by :EasySingle correct
26 Jun 2022, Shift 1 · Q39A thermally insulated vessel contains an ideal gas of molecular mass M and ratio of specific heats 1.4. Vessel is moving with speed $v$ …MediumSingle correct
17 Mar 2021, Shift 1 · Q8A polyatomic ideal gas has 24 vibrational modes. What is the value of $\gamma$ ?MediumSingle correct
17 Mar 2021, Shift 2 · Q18If one mole of the polyatomic gas is having two vibrational modes and $\beta$ is the ratio of molar specific heats for polyatomic gas…MediumSingle correct
4 Sep 2020, Shift 1 · Q8Match the $\mathrm{C_P/C_V}$ ratio for ideal gases with different type of molecules : Molecule Type | $\mathrm{C_P/C_V}$ (A) Monatomic |…EasyMatch the list

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.