Physics (AS & A Level) · May / June 2023 · Paper 12 · Question 22

A source X emits a sound wave of constant frequency f. The wave is subsequently received at a stationary detector Y. The frequency of the wave that is detected by Y is less than f. What could be the reason for this?

1. ABetween X and Y, the wave undergoes diffraction.
2. BBetween X and Y, the wave undergoes reflection.
3. CX is moving away from Y.
4. DX is moving towards Y.

As printed in the paper