Physics (AS & A Level) · Oct / Nov 2019 · Paper 12 · Question 22

A microphone is connected to a cathode-ray oscilloscope (CRO). When a tuning fork is struck and then held next to the microphone, the following waveform is shown on the display of the CRO. [waveform on CRO display] The time-base setting on the CRO is 2.00 ms per division. What is the best estimate of the frequency of the sound produced by the tuning fork?

1. A63 Hz
2. B170 Hz
3. C250 Hz
4. D500 Hz

As printed in the paper