The temperature of a gas is -78^ C and the average translational kinetic energy of its molecules is K . The temperature at which the average translational kinetic energy of the molecules of the same gas becomes 2 ~K is :

Correct answer: B. 117^ C aligned & K . E= nf_1 RT 2 \& ~T_ i =-78^ C arrow 273+[-78^ C]=195 ~K aligned K.E α T To double the K.E energy temp also become double aligned & T_ f =390 ~K & ~T_ f =117^ C aligned

JEE Main 20249 AprilEvening Shift

Exam: JEE Main
Year: 2024
Date: 9 April
Shift: Evening Shift
Subject: Physics
Chapter: Kinetic Theory of Gases

JEE Main 2024 · 9 April · Evening Shift · Physics · Kinetic Theory of Gases

The temperature of a gas is -78^ C and the average translational...

The temperature of a gas is

-78^{\circ} \mathrm{C}

and the average translational kinetic energy of its molecules is

\mathrm{K}

. The temperature at which the average translational kinetic energy of the molecules of the same gas becomes

2 \mathrm{~K}

is :

Options

A $127^{\circ} \mathrm{C}$
B $117^{\circ} \mathrm{C}$
C $-39^{\circ} \mathrm{C}$
D $-78^{\circ} \mathrm{C}$

Correct answer

B. $117^{\circ} \mathrm{C}$

Step-by-step solution

\begin{aligned}& \mathrm{K} . \mathrm{E}=\frac{\mathrm{nf}_1 \mathrm{RT}}{2} \& \mathrm{~T}_{\mathrm{i}}=-78^{\circ} \mathrm{C} \rightarrow 273+\left[-78^{\circ} \mathrm{C}\right]=195 \mathrm{~K} \end{aligned}

K.E

\alpha \mathrm{T}

To double the K.E energy temp also become double

\begin{aligned}& \mathrm{T}_{\mathrm{f}}=390 \mathrm{~K} \\ & \mathrm{~T}_{\mathrm{f}}=117^{\circ} \mathrm{C}\end{aligned}

Practice Kinetic Theory of Gases on Quantrex Academy →

More from Kinetic Theory of Gases

If 2 mole of an ideal monoatomic gas at temperature T , is mixed with 6 mole of another… JEE Main 2026 Given below are two statements: one is labelled as Assertion A and the other is labelled… JEE Main 2026 Given below are two statements: one is labelled as Assertion A and the other is labelled… JEE Main 2026 One gas of n_1 mole of molecules at temperature T_1 , volume V_1 , and pressure P_1 , and… JEE Main 2026 A mixture of carbon dioxide and oxygen has volume 8310 cm ^3 , temperature 300 K… JEE Main 2026 The mean free path of a molecule of diameter 5 × 10^ -10 ~m at the temperature 41^ ∘ C… JEE Main 2026 A gas of certain mass filled in a closed cylinder at a pressure of 3.23 kPa has… JEE Main 2026 Consider two boxes containing ideal gases A and B such that their temperatures, pressures… JEE Main 2026 Full Kinetic Theory of Gases list All JEE Main PYQs