Chapter 22657*P22.63Like a refrigerator, an air conditioner has as its purpose the removal of energy by heat from the coldreservoir.Its ideal COP isCOPK20 KCarnot=−==TTTchc28014 0.(a)Its actual COP is0 400 14 05 60...af−=−QQQQtcc∆∆∆560QtQtQtc∆−=560100660.kWaf=Qtc∆and Qtc∆=848. kW(b)QWQ=+eng:WtQtQtengkWkWkW∆=−=−=10 08 481 52.(c)The air conditioner operates in a cycle, so the entropy of the working fluid does not change.The hot reservoir increases in entropy byQThh=×=×10 0 103 600300120 1035..JssKJKejbgThe cold room decreases in entropy by∆SQTcc=−××848 103600280109 1035..sKThe net entropy change is positive, as it must be:
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