Two tuning forks produce `5 beats` when sounded together.` A` is in unison with ` 40 cm` length of a sonometer wire under a constant tension and `B` is in unison with the same wire of length `40.5 cm` under the same tension. Calculate of the forks.

Explanation

`n_(A) = (1)/( 2 xx 0.400) sqrt((T)/(m)) n_(B) = (1)/( 2 xx 0.405) sqrt((T)/(m))`
Dividing `(n_(A))/(n_(B)) = (405)/(400) ` (Obviously `n_(A) gt n_(B)`)
`:. N_(A) - n_(B) = 5` (`:.` There are `5 beats per second`)
or `(405)/(400) n_(A) - n_(B) = 5`
`(5)/( 400) n_(B) = 5`
`n_(B) = 5 xx (400)/( 5) = 400 Hz and n_(A) = 405 Hz`