Question

Imagine an ideal (Carnot) refrigerator that keeps helium in its liquid state, at a temperature of about 4.00 K. The refrigerator, with the helium container inside, is in a laboratory where the temperature is about 294 K. Because of the imperfection of the insulation, 2.00 J of heat is absorbed by the refrigerator each hour. How much electrical energy E must be used by the refrigerator to maintain a temperature of 4.00 K inside for one hour?

Answer 1

147 Joule per hour

Step-by-step explanation:

Cold temperature, T2 = 4 k

Hot temperature, T1 = 294 k

Heat absorbed, Q2 = 2 J per hour

Let the electrical energy is Q1.

by use of the condition of ideal refrigerator

`(Q_(1))/(Q_(2))=(T_(1))/(T_(2))`

`(Q_(1))/(2)=(294)/(4)`

Q1 = 147 Joule per hour