What Is the Coefficient of Performance for a Carnot Engine Run as a Heat Pump?

itryphysics
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Homework Statement


An ideal (Carnot) engine has an efficiency of 50 %
If it were possible to run it backward as a heat pump, what would be its coefficient of performance?



Homework Equations


COP = (TL) / (TH - TL )


The Attempt at a Solution


no temperatures are given. I just know that since e = 1 - TL / TH then TL / TH is 0.5 since the efficiency is 50%
 
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itryphysics said:

Homework Statement


An ideal (Carnot) engine has an efficiency of 50 %
If it were possible to run it backward as a heat pump, what would be its coefficient of performance?



Homework Equations


COP = (TL) / (TH - TL )


The Attempt at a Solution


no temperatures are given. I just know that since e = 1 - TL / TH then TL / TH is 0.5 since the efficiency is 50%

Okay, since TL is 0.5 TH what does that give for COP?
 
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