Question

Working Principle of Refrigerator
Give the working principle of refrigerator.

Answer 1

Refrigerator works on the principle of extraction of heat from cold objects (cold tank) and rejecting the heat to the atmosphere (hot sink), by absorbing electrical energy from the environment.

This is also called the heat pump.  In this there is a compressor works with electrical power.  The compressor compresses the refrigerant liquid/gas to very high pressure.  Then the gas/liquid is allowed to expand in the presence of the cold items stored inside the refrigerator.  The refrigerant takes heat from the items inside, during sudden expansion into gas.   This heat is released to the atmosphere.

Answer 2

Answer:

Refrigerator works on the principle of thermodynamics.

Explanation:

The law of thermodynamic says that the energy is transferred from a higher temperature to a lower temperature. But the energy has to be transferred from lower temperature to the higher temperature external work has to be applied.