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

Options

A. 2
B. 1
C. 4
D. 3

Answer

A

Explanation

`{:(A,B,C),(v-1,v,v+1):}`
Between `A & B 1 b//s 1`
`B & C 1 b//s 1`
`C & A 2 b//s (1)/(2) ((2)/(2))`
`rArr 2 b//s`