Question 46
Use tuning forks (or a small constant-frequency source), a plastic pipe at least 4 cm in diameter and about 70 cm long, a deep water container and a metre rule. Set up the equipment shown. Strike the tuning fork and hold it over the open end of the pipe. Move the pipe up or down in the water to vary its length above the water. Listen for increased loudness; strike again if necessary. Adjust until the sound is loudest, then measure the pipe length above water. Repeat with a tuning fork of different pitch.
