Three sound waves of equal amplitudes have frequencies (ν−1), ν, (ν+1). They superpose to give beats. The number of beats produced per second will be:

Correct answer: 2

Solution

The pairwise beat frequencies are 1, 1, and 2 Hz; the maximum number of beats per second is between (v+1) and (v-1), i.e. 2 Hz. Answer: 2.

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