Physics (AS & A Level) · Feb / March 2022 · Paper 12 · Question 25

A corridor is 13.2 m long and has closed doors that reflect sound at both ends. The speed of sound in the air in the corridor is 330 m s⁻¹. What is the lowest frequency of sound that could create a stationary wave in the corridor with a node halfway along it?

1. A0.040 Hz
2. B13 Hz
3. C25 Hz
4. D50 Hz

As printed in the paper