Q100 / 125 · BITSAT 2020 · Physics
In an adiabatic process, the pressure is increased by $\frac{2}{3} \% .$ If $\gamma=\frac{3}{2},$ then the volume decreases by nearly
- Correct answerA$\frac{4}{9} \%$
- B$\frac{2}{3} \%$
- C$1 \%$
- D$\frac{9}{4} \%$
Solution
$\mathrm{PV}^{3 / 2}=\mathrm{K}$
$\log \mathrm{P}+\frac{3}{2} \log \mathrm{V}=\log \mathrm{K}$
$\frac{\Delta \mathrm{P}}{\mathrm{P}}+\frac{3}{2} \frac{\Delta \mathrm{V}}{\mathrm{V}}=0$
$\frac{\Delta \mathrm{V}}{\mathrm{V}}=-\frac{2}{3} \frac{\Delta \mathrm{P}}{\mathrm{P}}$ or $\frac{\Delta \mathrm{V}}{\mathrm{V}}=\left(-\frac{2}{3}\right)\left(\frac{2}{3}\right)=-\frac{4}{9}$
Hence, the correct answer is option: 'A'.