Physics · Oct / Nov 2023 · Paper 12 · Question 20

Pot X and pot Y are both in a cool room. Pot X contains hot water below its boiling point. Pot Y is identical to pot X but contains water that is kept boiling by a hotplate underneath it. [diagram: pot X on kitchen surface, pot Y on hotplate of a cooker] What happens to the average kinetic energy of the particles in the liquid water in pot X and to the average kinetic energy of the particles in the liquid water in pot Y?

1. Akinetic energy of liquid particles in X: decreases; kinetic energy of liquid particles in Y: increases
2. Bkinetic energy of liquid particles in X: decreases; kinetic energy of liquid particles in Y: does not change
3. Ckinetic energy of liquid particles in X: stays the same; kinetic energy of liquid particles in Y: increases
4. Dkinetic energy of liquid particles in X: stays the same; kinetic energy of liquid particles in Y: does not change

As printed in the paper