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Keith_Richards [23]
3 years ago
7

How fast should the platform move, vp, for the person to detect a beat frequency of 7.00 hz ? take the speed of sound to be 344

m/s. express your answer numerically in meters per second using three significant figures. hints?
Physics
1 answer:
NeX [460]3 years ago
7 0
<span>Delta(f) =f0 * v_rel/c , where v_rel is the relative velocity between source and observer. The source is moving at a speed v but the sound bounced off the wall and the receiver is moving toward it too. So, Delta(f) = f0 (2 V) / c Hence V = c Delta(f) /(2 f0)= 344 m/s * (7.00Hz/(2*245Hz)) =4.91 m/s</span>
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