A sound of frequency 1500 Hz is emitted by a source which moves away from an observer and moves towards a cliff at a speed of 6 ms^(-1) (a) Calculate the frequency of the sound which is coming directly from the source. (b) Compute the frequency ofsound heard by the observer reflected off the cliff. Assume the speed of sound in air is 330 ms^(-1)

A sound of frequency 1500 Hz is emitted by a source which moves away f

1.	A sound of frequency 1500 Hz is emitted by a source which moves away from an observer and moves towards a cliff at a speed of 6 ms^(-1) (a) Calculate the frequency of the sound which is coming directly from the source. (b) Compute the frequency ofsound heard by the observer reflected off the cliff. Assume the speed of sound in air is 330 ms^(-1)
Answer» Solution :(a) SOURCE is moving away and observer is stationary, therefore, the frequency of soundheard DIRECTLY from source is `f. = (f)/((1 + (v_(s))/(v))) = (1500)/((1 + (6)/(330))) = 1473` Hz ( b) Sound is REFLECTED from the cliff and REACHES observer, therefore, `f. = (f)/((1 - (v_(s))/(v))) = (1500)/(( 1- (6)/(330))) = 1528 Hz`