Physics (AS & A Level) · May / June 2020 · Paper 12 · Question 25

A stationary person measures the speed and wavelength of the sound from a horn on a stationary vehicle. The person then repeats the measurements when the vehicle is approaching at a constant speed. Which row describes the measured wavelength and the measured speed of the sound wave from the moving vehicle when compared with the sound wave from the stationary vehicle?

1. Alonger / greater
2. Bshorter / greater
3. Clonger / same
4. Dshorter / same

As printed in the paper