Figure (16-E12) shows a source of sound moving along the X-axis at a speed of $22 m s^{- 1}$ continuously emitting a sound of frequency 2.0 kHz which travels in air at a speed of $330 m s^{- 1}$ . A listener Q stands on the Y-axis at a distance of 330 m from the origin. At t = 0, the source crosses the origin P. (a) When does the sound emitted from the source at P reach the listener Q ? (b) What will be the frequency heard by the listener at this instant? (c) Where will the source be at this instant ?

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Solution

Here, v=22 ms^{-5},

$n = 2 k H z, v_{a i r} = 330 m s^{- 1}$

(a)Since, $S = V_{n} t$

$\Rightarrow t = \frac{330}{330} = 1 s e c$

(b)n'=2 kHz

(Because frequency does not depend on distance).

(c)S=22 m away from P at x-axis

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Here, v=22 ms^{-5}, n=2kHz,vair=330ms−1 (a)Since, S=Vnt ⇒t=330330=1 sec (b)n'=2 kHz (Because frequency does not depend on distance). (c)S=22 m away from P at x-axis

Here, v=22 ms^{-5},

$n = 2 k H z, v_{a i r} = 330 m s^{- 1}$

(a)Since, $S = V_{n} t$

$\Rightarrow t = \frac{330}{330} = 1 s e c$

(b)n'=2 kHz

(Because frequency does not depend on distance).

(c)S=22 m away from P at x-axis