Physics (AS & A Level) · May / June 2020 · Paper 13 · Question 25

A stationary source S emits a sound wave of frequency f. The source now moves away from a stationary observer. Which statement is correct?

1. AThe frequency of the source S and the observed frequency are now both higher than f.
2. BThe frequency of the source S and the observed frequency are now both lower than f.
3. CThe frequency of the source S is now lower than f.
4. DThe observed frequency is now lower than f.

As printed in the paper