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If a stationary observer notes a change ...

If a stationary observer notes a change of 25% in the frequency of a whistle of an engine coming towards him, then the velocity of the engine is (velocity of sound = `332 m//s`)

A

`66.4 m//s`

B

`64 m//s`

C

`60 km//hr`

D

`32 km//hr`

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TARGET PUBLICATION-Sound-Exercise
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  4. A train A is travelling at a speed of 108 km hr^(-1). The train approa...

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  5. Two cars are approaching each other with same speed of 20 m//s. A man ...

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  6. An engine is moving on a circular track with a constant speed. It is b...

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  7. An engine driver moving towards a wall with a velocity of 60 m//s emit...

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  8. An object producing a pitch of 600 Hz approaches a stationary person i...

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  9. When both source and listener approach each other with a velocity equa...

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  10. The difference between the apparent frequency 71. of a source of sound...

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  11. If sound velocity is v, velocity of observer is v0 and velocity of sou...

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  12. Consider a source of sound S and an observer P. The frequency of sound...

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  13. A car is travelling with a velocity of 40 m//s towards a source of sou...

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  14. What should be the velocity of sound from a source w.r.t. an observer,...

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  15. The frequency of a whistle of the engine of an express train moving wi...

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  16. Two cars are moving on two perpendicular roads towards a crossing with...

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  17. An observer starts moving with uniform acceleration ‘a’ towards a stat...

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  18. The frequency of a note emitted by a source changes by 20% as it appro...

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  19. A source of sound is travelling towards a stationary observer. The fre...

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  20. A man is watching two trains, one leaving and the other coming in with...

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