A table is revolving on its axis at 5 revolutions per second. A sound source of frequency 1000 Hz is fixed on the table at 70 cm from the axis. The minimum frequency heard by a listener standing at a distance from the table will be (speed of sound $352ms^{- 1}$)

Question

Dr. Abubacker · Accepted Answer

(c) $v_{s} = r\omega = r 	imes 2\pi v$
$= \frac{70}{100} 	imes 2 	imes \frac{22}{7} 	imes 5 = 22ms^{- 1}$
Frequency is minimum when source is moving away from listener.
$v^{'} = \frac{u 	imes v}{u + u_{s}} = \frac{352 	imes 1000}{352 + 22} = 941\ Hz$

Q. A table is revolving on its axis at 5 revolutions per second. A sound source of frequency 1000 Hz is fixed on the table at 70 cm from the axis. The minimum frequency heard by a listener standing at a distance from the table will be (speed of sound $352ms^{- 1}$)

Explanation

Reviewed by Dr. Abubacker

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