A refrigerator requires 200Jof work and exhausts 600Jof heat per cycle. What is the refrigerator’s coefficient of performance?

Short Answer

Expert verified

The refrigerator's coefficient of performance is2

Step by step solution

01

Step :1 Introduction 

Refrigerator is an example of heat pomp . All types of heat engines are capable of extracting heat from an object continuously with the help of an input energy . In a refrigerator, input energy is provided by electrical energy being used by it .

Its efficiency is measured in terms of coefficient of performance which is as follows.

COP = Heat extracted from object / Energy used by machine

Total energy given out by heat pump to surrounding is total of heat extracted and energy input.

02

Step :2 Explanation 

That 600 J is total heat drained out in one cycle, and heat given as input to the pump is W=200J, we can find the energy taken out from the cold reservoir.

Qc=QhW=600200=400J_

03

Step :3 Coefficient of performance 

Considering this, the refrigerator's performance coefficient will be

K=QcW=400200=2

K=QcW=400200=2

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