MCQ
The average degree of freedom per molecule of a gas is $6$. The gas performs $25\ J$ work, while expanding at constant pressure. The heat absorbed by the gas is .... $J$
- A$75$
- ✓$100$
- C$150$
- D$125$
✓
Answer
Correct option: B.
$100$
b
$f = 6$
$f = 6$
$\gamma = 1 + \frac{2}{f} = 1 + \frac{2}{6} = \frac{4}{3}$
$\frac{{\Delta W}}{{\Delta Q}} = \left( {1 - \frac{1}{\gamma }} \right)$
==> $\frac{{25}}{{\Delta Q}} = \left( {1 - \frac{1}{{4/3}}} \right)$
$ = 1 - \frac{3}{4} = \frac{1}{4}$
==> $\Delta Q = 25 \times 4 = 100\,Joule$
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