Thermodynamics - Result Question 35
37. At $27^{\circ} C$ a gas is compressed suddenly such that its pressure becomes $(1 / 8)$ of original pressure. Final temperature will be $(\gamma=5 / 3)$
(a) $420 K$
(b) $300 K$
(c) $-142^{\circ} C$
(d) $327^{\circ} C$
[1989]
Topic 3: Carnot Engine, Refrigerator & Second Law of Thermodynamics
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Answer:
Correct Answer: 37. (c)
Solution:
- (c) $T_1^{\gamma} P_1^{1-\gamma}=T_2^{\gamma} P_2^{1-\gamma}$
$\Rightarrow(\frac{T_2}{T_1})^{\gamma}=(\frac{P_1}{P_2})^{1-\gamma}$
$\Rightarrow T_2=T_1 \cdot(\frac{P_1}{P_2})^{\frac{1-\gamma}{\gamma}}=300 \times(8)^{-2 / 5}=142^{\circ} C$
