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A man standing on a platform observes th...

A man standing on a platform observes that the frequency of the sound of a whistle emitted by a train drops by 140 Hz. If the velocity of sound in air is 330 m/s and the speed of the train is 70 m/s, the frequency of the whistle is

A

571 Hz

B

800 Hz

C

400 Hz

D

260 Hz

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The correct Answer is:
B
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AAKASH INSTITUTE-WAVES-Assignment (Section-A)
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  4. Two waves of equal amplitude when superposed, give a resultant wave ha...

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  5. The change in phase, if a wave is reflected at a less dense surface, i...

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  9. The ratio of fundamental frequencies of an open organ pipe and a cloed...

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  10. if the first overtone of a closed pipe of length 50 cm has the same fr...

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  11. Two waves of frequencies 6 Hz and 10 hz are superposed. The beat frequ...

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  19. A listener and a source of sound are moving with the same speed in the...

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