If a source emitting waves of frequency f moves towards an observer with a velocity `(v)/(4)` and the observer moves away from the source with a velocity `(v)/(6)`, the apparent frequency as heard by the observer will be (v=velocity of sound)

Options

A. `(14)/(15)f`
B. `(14)/(9)f`
C. `(10)/(9)f`
D. `(2)/(3)f`

Answer

C

Explanation

When source and observer both are moving in the same direction and observer is head of source, then apparent frequency.
`f'=(v-v_(0))/(v-v_(s))f`
`=(v-(v)/(6))/(v-(v)/(4))=((5v)/(6))/((3v)/(4)f)=(10)/(9)f`