Three sound waves of equal amplitudes have frequencies $(n - 1 ), n, (n + 1 ).$ They superimpose to give beats. The number of beats produced per second will be
NEET 2016,AIEEE 2009, Medium
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net beat frequency $=LCM$ of individual beat frequencies
$=LCM\; of $[$(n,n-1),(n,n+1)$,$(n-1,n+1)]$$[(n,n-1),(n,n+1),(n-1,n+1)]$
$=LCM \;of $$(1,1,2)(1,1,2) $$=2\;Hz$
So, no. of beats per second $=2$
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