Question

A source of sound is travelling with a velocity of `30(m)/(s)` towards a stationary observer. If actual frequency of source is 1000 Hz and the wind is blowing with velocity `20(m)/(s)` in a direction at `60^@C` with the direction of motion of source, then the apparent frequency heard by observer is (speed of sound is `340(m)/(s)`)
A. 1011 Hz
B. 1000 Hz
C. 1094 Hz
D. 1086 Hz

Answer 1

Correct Answer - C
`f=((v+v_m)/(v+v_m-v_(source)))1000`
`=((340+20cos60^@)/(340+20cos60^@-30))1000`
`=1094Hz`