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Two trains A and B are moving in the sam...

Two trains A and B are moving in the same direction with velocities 30 m/s and 10 m/s respectively, B is behind from A, blows a horn of frequency 450 Hz. Then the apparent frequency heard by B is (The velocity of sound is 330 m/s) :-

A

425 Hz

B

300 Hz

C

450 Hz

D

350 Hz

Text Solution

Verified by Experts

The correct Answer is:
A
`f_(B)=f_(a)((v+v_(B))/(v+v_(A)))=450((330+10)/(330+30))=425 Hz`
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ALLEN -WAVES AND OSCILLATIONS-Part-1(Exercise-01)
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  13. Two tuning forks having frequency 256 Hz (A) and 262 Hz (B) tuning for...

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  16. A sound absorber attenuates the sound level by 20 dB. The intensity de...

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  17. A whistle giving out 450 H(Z) approaches a stationary observer at a sp...

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  18. A person observes a change of 2.5 % in frequency of sound of horn of a...

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  19. Two trains A and B are moving in the same direction with velocities 30...

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