Refrigerators&Heat Pumps Flashcards
1
Q
How is a refrigerator different from a heat engine
A
It take energy from a cold reservoir to a warmer sink
Work is required for this to happen
2
Q
How does a heat pump work?
A
Heat energy is taken from a cold reservoir to a hot sink with work
3
Q
What is the Coefficient of performance of. Heat pump
A
It measures how efficient a heat pump is
4
Q
What is the equation for COP
A
Power from heat pump/power used by compressor
5
Q
What is the equation for COP of Refrigerator
A
Qc/ Qh-Qc
6
Q
How does a refrigerator work
A
Compressor turns gas into a warm liquid
The fan blows air on the warm liquid and the heat energy is lost to the surroundings
The liquid goes through an evaporator and the liquid loses its energy to its surroundings
The cold gas then absorbs heat energy from the fridge
