Two Whistles A And B Produce Notes Of Frequencies 660 Hz And 596 Hz Respectively. There Is A Listener At The Midpoint Of The Line Joining Them. Both The Whistle B and The Listener Start Moving With Speed 30 M/s Away From Whistle A. If Speed Of Sound Be 330 M/s, How Many Beats Will Be Heard By The Listener?

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Two whistles A and B produce notes of frequencies 660 Hz and 596 Hz respectively. There is a listener at the midpoint of the line joining them. Both the whistle B and the listener start moving with speed 30 m/s away from whistle A. If speed of sound be 330 m/s, how many beats will be heard by the listener?


Correct option is



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(v = 330 m/s):


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