Question
A refrigerator, whose coefficient of performance is 5, extracts heat from the cooling compartment at the rate of 250 per cycle. How much heat per cycle is discharged to the room?
✓
Answer
$\beta=\frac{\text{Q}_2}{\text{Q}_1-\text{Q}_2}$ or $5=\frac{250}{\text{Q}_1-250}$
$5\text{Q}_1-1250=250$ or $\text{Q}_1=\frac{1500}{5}\text{J}=300\text{J}$
$\therefore$ Heat discharged per cycle to the room = 300J.
$5\text{Q}_1-1250=250$ or $\text{Q}_1=\frac{1500}{5}\text{J}=300\text{J}$
$\therefore$ Heat discharged per cycle to the room = 300J.
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