Question

With the help of a block diagram , write the working principal of a refrigerator and obtain the expression for its coefficient of performance

Answer 1

Answer:

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Explanation:

Ironically, refrigerators keep things cold because of the nature of heat. The Second Law of Thermodynamics essentially states that if a cold object is placed next to a hot object, the cold object will become warmer and the hot object will become cooler. The 2nd law speaks of entropy I think the zeroth law is more applicable . A refrigerator does not cool items by lowering their original temperatures; instead, an evaporating gas called a refrigerant draws heat away, leaving the surrounding area much colder. Refrigerators and air conditioners both work on the principle of cooling through evaporation.

The coefficient of performance, COP, of a refrigerator is defined as the heat removed from the cold reservoir Q cold i.e. inside a refrigerator ,  divided by the work W done to remove the heat i.e. work done by a compressor.

                                                     

                                       COP= Qcold divided by W