Medium MCQ +4 / -1 PYQ · JEE Mains 2024

A sample of gas at temperature $T$ is adiabatically expanded to double its volume. Adiabatic constant for the gas is $\gamma=3 / 2$. The work done by the gas in the process is:

$(\mu=1 \text { mole })$

  1. A $R T[2 \sqrt{2}-1]$
  2. B $R T[2-\sqrt{2}]$ Correct answer
  3. C $R T[1-2 \sqrt{2}]$
  4. D $R T[\sqrt{2}-2]$

Solution

<p>$$\begin{aligned} & w=\frac{-n R}{\gamma-1}(\Delta T) \\ &=\frac{-R}{1 / 2}\left(\frac{T}{\sqrt{2}}-T\right) \\ &=2 R\left(\frac{\sqrt{2} T-T}{\sqrt{2}}\right) \\ &=R T(2-\sqrt{2}) \\ & \therefore \quad T V_\gamma^{-1}=\text { cons. } \\ & T V_\gamma^{-1}=T_f(2 V)^{\gamma-1} \\ & T_f=\frac{T}{\sqrt{2}} \end{aligned}$$</p>

About this question

Subject: Physics · Chapter: Thermodynamics · Topic: Thermodynamic Processes

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 →