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3 months ago

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A household refrigerator runs one-fourth of the time and removes heat from the food compartment at an average rate of 800 kJ/h.

If the COP of the refrigerator is 2.2, determine the power the refrigerator draws when running.

1 answer:

Ostrovityanka [3.2K]3 months ago

4 0

Answer:

1454.54 kJ/h or 0.404 kW

Explanation:

Provided:

The heat being removed by the refrigerator is 800 kJ/h.

The refrigerator's coefficient of performance (COP) is 2.2.

Since the refrigerator operates for one-fourth of the time,

it effectively removes heat, Q = $4\times 800 kJ/h$ = 3200 kJ/h.

Next, the power consumed by the refrigerator during its operation is calculated as:

$\frac{Q}{COP}$

= $\frac{3200 kJ/h}{2.2}$ .

= 1454.54 kJ/h

Thus, the fridge uses 1454.54 kJ/h

or 0.404 kW (given 1 kW = 3600 kJ/h).

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