COP refrigerator vs COP Heat Pump

[ChunkymonkeyI]

Homework Statement

I just want to know when do I use the formula for COP refrigerator vs COP Heat pump. If the heat is absorbing something then what formula do I use

Homework Equations

3. The Attempt at a Solution [/b}
Uh I just trying 2 figure out the concept so Idk how 2 solve it lol

 

[Spinnor]

This explains it i think,

http://en.wikipedia.org/wiki/Coefficient_of_performance

Found via,

https://www.google.com/webhp?hl=en#...w.,cf.osb&fp=cb785b2a153d08fa&biw=734&bih=439

 

[Andrew Mason]

Homework Statement

I just want to know when do I use the formula for COP refrigerator vs COP Heat pump. If the heat is absorbing something then what formula do I use

If you think of COP as: output/input you will avoid confusion. If it is a heat pump, the output is the heat flow to the hot reservoir. If it is a refrigerator the output is the heat flow from the cold reservoir. The input is the work done.

So, for a refrigerator: COP = output/input = Qc/W

and for a heat pump: COP = output/input = Qh/W = (Qc + W)/W = Qc/W + 1

AM