An observer moves towards a stationary source of sound with a speed `((1)/(5))`th of the speed of sound. The wavelength and frequency of the source emitted are `lamda` and f, respectively. The apparent frequency and wavelength recorded by the observer are, respectively.

Options

A. `1.2 f, lambda`
B. `f, 1.2 lambda`
C. `0.8 f, 0.8 lambda`
D. `1.2 f, 1.2 lambda`

Answer

A

Explanation

`f.=((v+v_(o))/(v))f=((v+(v)/(5))/(v))f=1.2f`
Since, source is stationary, so wavelength remains unchanged for observer.