Physics (AS & A Level) · May / June 2020 · Paper 11 · Question 24

A long glass tube is almost completely immersed in a large tank of water. A tuning fork is struck and held just above the open end of the tube as it is slowly raised. A louder sound is first heard when the height h of the end of the tube above the water is 18.8 cm. A louder sound is next heard when h is 56.4 cm. The speed of sound in air is 330 m s–1. What is the frequency of the sound produced by the tuning fork?

1. A220 Hz
2. B440 Hz
3. C660 Hz
4. D880 Hz

As printed in the paper