Question

A cyclic Process is shown in the given $P-T$ diagram for an ideal gas. Which of the following curves shows the same process in $V-T$ diagram ?

• A.
• B.
• C.
• D.

Answer 1

The correct option is D

It is clear that during the process $\text{C to A}$:
$P$ is constant and temperature is decreasing.
As, $PV=nRT$ for ideal gas.
Hence, $V\propto T$ during the process $\text{C to A}$. Temperature is decreasing, therefore volume will also decrease during this process.

Temperature is constant from $\text{B to C}$ and pressure is decreasing, hence in $V-T$ curve Temperature is also going to be constant from $\text{B to C}$.
Here, $PV=\text{constant}$.
Hence, as $P$ will decrease $V$ will increase during $B-C.$

It is clear that during the process $\text{A to B}$:
$P\propto T$
As, $PV=nRT$ for ideal gas.
Hence, $V$ is constant during process $\text{A to B}$ and temperature will increase.

Hence, graph $\left(d\right)$ satisfies all the conditons.