What causes cooling in an air conditioner?
- ABy compressing and releasing gas
- BBy evaporation of water
- CBy compressing water
- DBy compressing a solid
Show answer and explanation
Correct answer: (a) By compressing and releasing gas
Explanation
An air conditioner cools by compressing a refrigerant gas and letting it expand. Compressed, the gas gets hot and gives off its heat outside; expanding, it cools sharply and takes in heat from the room's air.
So heat is pumped from inside the room to the outside.