Physics (AS & A Level) · May / June 2026 · Paper 11 · Question 24

A train is travelling with a constant velocity. It operates its whistle as it moves directly towards a student. The whistle emits a continuous sound of constant frequency. Which graph shows the variation with time t of the frequency f of the sound heard by the student?

1. Agraph A
2. Bgraph B
3. Cgraph C
4. Dgraph D

As printed in the paper