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A heat pump is a refrigerator that uses the inside of a building as a hot-temp reservoir in the winter and the outside of the building as a hot-temp reservoir in the summer. So.....

For a carnot refrigerator engine operating between 25C and 40C in the summer, what is the coefficient of performance?And, for each joule of heat trasnfer from the cooler reservoir per cycle, how many joules of work are done by the refrigerator engine? Is this work positive or negative....and, what additional information is needed to determine an appropriate heat pump for a building?

Ok, so I figured out the COP....

COP=1/ [(Th/Tc)-1]

COP=1/ [(313k/298K)-1]

COP=19.9

But thenn I get confused on the second part

I know that

COP=Qc/W

W=Qc/COP

so is the value for Qc just 1 J? THat is the part i am having trouble with, and the work is negative correct? because it is work done by the system?

And, any thouhts on the last part?

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# Homework Help: Refrigerator problem!

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