Physics (AS & A Level) · May / June 2019 · Paper 12 · Question 26

In one of the first experiments to demonstrate the Doppler effect, a train was filled with trumpeters all playing a note of frequency 440 Hz. The difference in observed frequency of the note as the train directly approached a stationary observer was 22 Hz. The speed of sound was 340 m s⁻¹. At which speed was the train moving?

1. A15.4 m s⁻¹
2. B16.2 m s⁻¹
3. C17.0 m s⁻¹
4. D17.9 m s⁻¹

As printed in the paper