Medium MCQ +4 / -1 PYQ · JEE Mains 2023

Given below are two statements :

Statement I : The temperature of a gas is $-73^\circ$C. When the gas is heated to $527^\circ$C, the root mean square speed of the molecules is doubled.

Statement II : The product of pressure and volume of an ideal gas will be equal to translational kinetic energy of the molecules.

In the light of the above statements, choose the correct answer from the option given below :

  1. A Statement I is true but Statement II is false Correct answer
  2. B Both Statement I and Statement II are true
  3. C Statement I is false but Statement II is true
  4. D Both Statement I and Statement II are false

Solution

$T_{i}=200 \mathrm{~K} \quad\quad v_{\mathrm{rms}} \propto \sqrt{T}$ <br/><br/> $T_{f}=800 \mathrm{~K}$ <br/><br/> $\frac{V_{i}}{V_{f}}=\sqrt{\frac{T_{i}}{T_{f}}}=\sqrt{\frac{200}{800}}=\sqrt{\frac{1}{4}}=\frac{1}{2}$ <br/><br/> $V_{f}=2 V_{i}$ <br/><br/> Translational K.E. $=\left(\frac{3}{2} P V\right)$

About this question

Subject: Physics · Chapter: Thermodynamics · Topic: Zeroth and First Law

This question is part of PrepWiser's free JEE Main question bank. 271 more solved questions on Thermodynamics are available — start with the harder ones if your accuracy is >70%.

Drill 25 more like these. Every day. Free.

PrepWiser turns these solved questions into a daily practice loop. Chapter-wise drills, full mocks, AI doubt chat. No auto-renew.

Start free →