C1 - Heat Pumps (Refrigerators)

Question 1

What do heat pumps do?

Answer 1

Transfer heat energy from colder objects to hotter objects

Question 2

What type of devices transfer heat energy from colder objects to hotter objects?

Answer 2

Heat pumps

Question 3

What are the four parts of a refrigerator?

Answer 3

Compressor, Condenser coils, Expansion device, Evaporator coils

Question 4

What does the compressor do in a fridge?

Answer 4

Compresses coolant vapour, which heats it up

Question 5

What component in a fridge compresses coolant vapour, which heats up the coolant?

Answer 5

Compressor

Question 6

What do the condenser coils do in a fridge?

Answer 6

Remove heat from the coolant by transferring it to the surroundings

Question 7

What component in a fridge removes heat from the coolant by transferring it to the surroundings?

Answer 7

Condenser coils

Question 8

What does the expansion device do in a fridge?

Answer 8

Expand the liquid coolant, partially turning it into a vapour and decreasing its temperature

Question 9

What component in a fridge expands the liquid coolant, partially turning it into a vapour and decreasing its temperature

Answer 9

Expansion device

Question 10

What do the evaporator coils do in a fridge?

Answer 10

Remove heat energy from the fridge by transferring it to the coolant

Question 11

What component in a fridge removes heat energy from the fridge by transferring it to the coolant?

Answer 11

Evaporator coils

Question 12

What affects the efficiency of a fridge?

Answer 12

The temperature difference between the hot coolant and the surroundings

Question 13

When is a fridge most efficient?

Answer 13

When there is a large temperature difference between the hot coolant and the surroundings (e.g. winter)

Question 14

When is a fridge least efficient?

Answer 14

When there is a small temperature difference between the hot coolant and the surroundings (e.g. summer)