Question 818: Thermodynamics & KTG

Question

An ideal refrigerator has freezer at a temperature of $$-13^{\circ} \mathrm{C}$$. The coefficient of performance of the engine is 5. The temperature of the air (to which heat is rejected) is

Accepted Answer

Coefficient of performance, $$\beta=\frac{T_2}{T_1-T_2}$$
Given that, $$\beta=5$$ and $$\mathrm{T}_2=-13^{\circ} \mathrm{C}=260 \mathrm{~K}$$
$$\begin{array}{ll}
	herefore & \frac{260}{\mathrm{~T}_1-260}=5 \
	herefore & 5 \mathrm{~T}_1-1300=260 \
	herefore & \mathrm{T}_1=\frac{1560}{5}=312 \mathrm{~K} \
	herefore & \mathrm{T}_1=39^{\circ} \mathrm{C}
\end{array}$$

Answer

$$320^{\circ} \mathrm{C}$$

Answer

$$39^{\circ} \mathrm{C}$$

Answer

$$325 \mathrm{~K}$$

Answer

$$325^{\circ} \mathrm{C}$$

Thermodynamics & KTG

An ideal refrigerator has freezer at a temperature of $-13^{\circ} \mathrm{C}$. The coefficient of performance of the engine is 5. The temperature of the air (to which heat is rejected) is

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