A source of sound is travelling towards a stationary observer. The frequency of sound heard by the observer is of three times the original frequency. The velocity of sound is v m / sec . The speed of source will be

Options

A. `(2)/(3)v`
B. `v`
C. `(3)/(2)v`
D. `3v`

Answer

A

Explanation

We use
`n' = n((v)/(v - v_(S))) implies (n')/(n) = ((v)/(v - v_(S)))`
implies ` (v)/(v - v_(S)) = 3 impliesv_(s) = (2v)/(3)`.