Which frequency would be the third harmonic in a series for an open-pipe resonator if the fundamental is 440 Hz

1320 Hz

Explanation:

The third harmonic is given as 3fo, where fo is the fundamental frequency.

The fundamental frequency is the lowest frequency that can occur in a pipe. In an open pipe, both even and odd harmonics occur which are multiples of the fundamental frequency fo. Hence the harmonics in an open pipe are; 2fo, 3fo,4fo etc.

For the third harmonic; 3fo = 3 (440 Hz) = 1320 Hz

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