A source of sound is travelling towards a stationary observer. The frequency of sound heard by the observer is `25 %` more than the actual frequency. If the speed of sound is `v`, that of the source is

Options

A. `v//5`
B. `v//4`
C. `v//3`
D. `v//2`

Answer

A

Explanation

`{:(rarr v_(s),,larr v_(o) = 0),(overset(*)(S),overset(v)rarr,overset(*)(O)):}`
`f' = f((v)/(v-v_(s)))`
`1.25f = f((v)/(v-v_(s)))`
`1.25 v-1.25 v_(s) = v rArr v_(s) = v//5`