Question

Select the correct order of steps in which a working substance(gas) goes through in a refrigerator.

(a) Expansion of gas, absorption of heat, heating of vapour, release of heat

(b) Absorption of heat, expansion of gas, heating of vapour, release of heat

(c) Heating of vapour, expansion of gas, absorption of heat, release of heat

(d) Heating of vapour, absorption of heat, expansion of gas, release of heat

I got this question during an online interview.

The query is from Thermodynamics topic in section Thermodynamics of Physics – Class 11

Answer 1

Right answer is (a) Expansion of gas, absorption of heat, heating of vapour, release of heat

Best explanation: In a refrigerator, the working substance(gas) first gets expanded from high to low pressure which cools it into a vapour-liquid mixture. Then heat is absorbed from the region to be cooled. Then the external work done on the system heats up the vapour. Finally, the vapour’s heat is released to the surroundings.