Physics - Heat & Thermo Question with Solution | TestHub

Compare the points A and B:

$P_A{V}_A=P_0(2V_0)=2P_0{V}_0$

$P_B{V}_B=(2P_0)(V_0)=2P_0{V}_0$

$P_A{V}_A=P_B{V}_B$

Both points lie on the same isotherm, and the curve A to B is that isotherm (isothermal process). So:

$\Delta T=0\Rightarrow \Delta U=0$

The volume decreases from $2V_0$ to $V_0$, so the gas is compressed. Work is done on the gas:

$W<0$

First law:

$Q=\Delta U+W=0+W=W<0$

Q is negative, so the gas gives out heat. The process is exothermic.

Answer: (A) exothermic process