Question

A cyclic process $ABCA$ is shown in $PT$ diagram. When presented on $PV$ , it would

• A.
• B.
• C.
• D.

Answer 1

Answer: (C)

The ideal gas equation is given by,
$PV=nRT$ ; where $n$ is number of moles and $R$ is gas constant.
From $A$ to $B$ , the pressure is constant and temperature is decreasing, hence volume will also decrease ( $V\propto T$ )
From $B$ to $C$ , the temperature is constant and pressure is decreasing, so the volume will increase as,
$V\propto \frac{1}{P}$
In $C$ to $A$ , the slope is constant, i.e.,
$\frac{P}{T}=\frac{nR}{V}=constant$ ; so the volume will be constant.
From the above analysis the graph will look like,