A stationary source of sound is emitting sound of frequency `500Hz`. Two observers `A` and `B` lying on the same line as the source, observe frequencies `480Hz` and `530 Hz` respectively. The velocity of `A` and `B` respectively are (in `m//s`), speed of sound `=300m//s`.

Options

A. 8,18
B. 16,14
C. 12,18
D. 12,16

Answer

C

Explanation

Higher frequency heard will be when observer would move towards the source and lower frequency heard will be when observes moves away from the source.
`therefore 530 = 500 [ (300 + v_(01))/(300 - 0)] rArr v_(01) = 18 m// s`
Also , `480 = 500[(300 - v_(02))/(300 - 0)] rArr V_(02) = 12 m//s`