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A siren emitting sound of frequency 800 ...

A siren emitting sound of frequency 800 Hz is going away from a static listener with a speed of 30 m/s. The frequency of sound heard by listener is (velocity of sound = 300 m/s) :

A

727.3 Hz

B

481.2 Hz

C

644.8 Hz

D

286.5 Hz.

Text Solution

Verified by Experts

The correct Answer is:
A
`v. = ((V)/(V + U_(s)) ) v = ((300)/(300 + 30)) 800 `
= 727.3 Hz
correct choice is (a).
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