Question

A refrigerator is designed to release 750
calories of heat per second. If the range
of its operation is 5 degree Celsius to 25
degree Celsius, then its power is:
A.
226 W
B.
300 W​

Answer 1

b) 300 w

hope it helps you ✌️

Answer 2

Answer:

The power consumed by the refrigerator is 226w.

Explanation:

The coefficient of performance of the refrigerator is given as,

$\beta=\frac{Q_2}{W}=\frac{T_2}{T_1-T_2}$

β=coefficient of performance

Q₂=heat released by the refrigerator

T₁=temperature of a hot bath in kelvin

T₂=temperature of cold bath in kelvin

W=work to be done per second=power required

From question,

Q₂=750 cal=750 ×4.2=3150J   (∴ 1cal=4.2Joule)

T₁=273+25=298K

T₂=273+5=278K

$\frac{3150}{W}=\frac{278}{298-278}=\frac{278}{20}$

$W=\frac{3150\times 20}{278}=226 w$

Hence, the power consumed by the refrigerator is 226w.