Question

Among given curves, which one could represent isothermal process?

• A. Curve $A$
• B. Curve $B$
• C. Curve $C$
• D. None of the curves could represent isothermal process

Answer 1

Answer: (A)

In isothermal process, temperature is constant.
From ideal gas equation, $pV=\mu RT$
At constant temperature, $pV=$ constant
So, with decreasing pressure $p,V$ must increase to keep product $pV$ constant.
This inverse relation between $p$ and $V$ is depicted correctly by curve $A$,
where $p$ decreases with increasing $V$.