Sound waves from a tuning fork `A` reacha point `P` by two separate paths `ABP` and `ACP`. When `ACP` is greater than `ABP` by `11.5 cm`, there is silence at `p`. When the difference is `23 cm` the sound becomes loudest at `P` and `34.5 cm` there is silence again and so on. Calculate the minimum frequency of the fork if the velocity of sound is taken to be `331.2 m//s`.

Explanation

`(lambda)/(2) = 11.5 cm` or `lambda = 23 cm` or `0.23 m`
`f = (nu)/(lambda) = (331.2)/(0.23) = 1440 H_(Z)`