Level 1: Close One End of an Open Pipe: Does the Note Go Up?
Match the overtones of two pipes.
The first overtone of a pipe closed at one end has the same frequency as the first overtone of an open pipe 60 cm long. Ignoring end corrections, the length of the closed pipe is:
A closed pipe has only odd harmonics, so its first overtone is its third harmonic, 3v/4L. An open pipe has all the harmonics, so its first overtone is its second harmonic, 2v/2L.
The closed pipe is 45 cm long. Taking the first overtone of a closed pipe to be its second harmonic, which a closed pipe does not have, gives 30 cm instead.
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