0.346 kilowatt
Here, we have to find out the power required to remove heat from refrigerated space.
We know that, a refrigerator is a reversible Carnot’s engine working backwards.
For a carnot engine
we have
=
where W = work done
Q1 = heat absorbed
T1 = temperature of source
T2 = temperature of sink
Also,
From a refrigerator
=
where
T1 temp of room (higher temperature)
T2 - temperature of refrigerated space (food material)
Q2 - heat absorbed from the substance
W - work done for absorbing the heat in this process it is given
Q2 = 50 Kcal = 50 ×
103 cal
= 50 ×
103 × 4.2 J
T1 = 27°C = 300 K
T2 = 0° C = 273
That is
=
=
W = 50 ×
103 × 4.2 ×
J
We have,
Power
P =
=
and time , t = 1 minute = 60 seconds
P =
watt
= 0.346 watt
Therefore, the power required to remove heat from the refrigerated space at the rate of 50 kilocalorie per minute = 0.346 kW.