MCQ
In an isothermal process the volume of an ideal gas is halved. One can say that
- AInternal energy of the system decreases
- BWork done by the gas is positive
- ✓Work done by the gas is negative
- DInternal energy of the system increases
✓
Answer
Correct option: C.
Work done by the gas is negative
c
(c) For isothermal process
$dU = 0$ and work done $ = dW = P({V_2} - {V_1})$
$\;{V_2} = \frac{{{V_1}}}{2} = \frac{V}{2}$
(c) For isothermal process
$dU = 0$ and work done $ = dW = P({V_2} - {V_1})$
$\;{V_2} = \frac{{{V_1}}}{2} = \frac{V}{2}$
$dW = - \frac{{PV}}{2}$
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