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The frequency of a radar is 780 MHz. Aft...

The frequency of a radar is 780 MHz. After getting reflected from an approaching aeroplane, the apparent frequency is more than the actual frequency by 2.6 kHz. The aeroplane has a speed of

A

`2Km//se`

B

`1Km//se`

C

`0.5Km//s`

D

`0.25Km//s`

Text Solution

Verified by Experts

The correct Answer is:
C
`Deltan=((2V_(s))/(C ))n`
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NARAYNA-WAVES-Exercise-I (C.W)
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  4. The frequency of a radar is 780 MHz. After getting reflected from an a...

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  5. An observer moves towards a stationary source of sound, with a veloci...

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  6. A train is moving at 30 m//s in still air. The frequency of the locomo...

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  7. A vehicle, with a horn of frequency n is moving with a velocity of 30 ...

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

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  9. A truck blowing horn of frequency 500Hz travels towards a vertical mou...

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  10. One train is approaching an observer at rest and another train is rece...

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  11. A tuning fork of frequency 328Hz is moved towards a wall at a speed of...

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  12. The frequency of the sound of a car horn as recorded by an observer to...

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  13. Two trains are approaching each other on parallel tracks with same vel...

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  14. A girl swings in a cardle with period pi//4 second and amplitude 2m. A...

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  15. The difference between the apparent frequency of a source of sound as ...

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  16. Two different sound sources S(1) and S(2) have frequencies in the rati...

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  17. A stationary source emitting sound of frequency 680Hz is at the origin...

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  18. A source S emitting sound of frequency 300Hz is fixed on block A which...

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  19. An observer is standing 500 m away from a vertical hill. Starting betw...

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  20. A star is moving away from the earth with a velocity of 10^(5) m/sec. ...

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