A source of sound is moving with a uniform
speed along a circle. The frequency of sound as
heard by listener stationed at the centre of the
path
(a) Increases
(b) Decreases
(c) Remains the same
(d) May increase and decrease alternately
Answers
Answer: The frequency of the sound as heard by Listener stationed at the centre of the path will Remain the Same.
Explanation:
Since the distance between the source and observer does not change in this case. Hence, the apparent frequency remains the same.
Extra Explanation :-
The Doppler effect is the change in frequency of a wave in relation to an observer who is moving relative to the wave source. It is named after the Austrian physicist Christian Doppler, who described the phenomenon in 1842.
A common example of Doppler shift is the change of pitch heard when a vehicle sounding a horn approaches and recedes from an observer. Compared to the emitted frequency, the received frequency is higher during the approach, identical at the instant of passing by, and lower during the recession.