Physics (AS & A Level) · May / June 2019 · Paper 11 · Question 25

A stationary insect on the surface of water creates circular waves with its legs, as shown in diagram 1. The insect begins to travel to the right as shown in diagram 2. Which row describes the change to the waves at X caused by the movement of the insect?

1. Afrequency decreases; wave speed increases
2. Bfrequency decreases; wave speed stays the same
3. Cfrequency increases; wave speed increases
4. Dfrequency increases; wave speed stays the same

As printed in the paper