A Carnot heat pump supplies heat to a house at a rate of 48000 kJ/h to maintain its temperature constant at 20°C. If the temperature of the outdoors is 5°C, the power required to operate this heat pump is

Question

Quizplus · Accepted Answer

Solved by EES Software. Solutions can be verified by copying-and-pasting the following lines on a blank EES screen. 
TL=5 "C"
TH=20 "C"
QH=48000/3600 "kJ/s"
COP=(TH+273)/(TH-TL)
COP=QH/Win
"Some Wrong Solutions with Common Mistakes:"
QH=W1_Win*TH/(TH-TL) "Using temperatures in C"
QH=W2_Win "Setting work equal to heat supply"
QH=W3_Win/COP "Dividing by COP instead of multiplying" 
QH=W4_Win*(TL+273)/(TH-TL) "Using COP of refrigerator"

A Carnot Heat Pump Supplies Heat to a House at a Rate