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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

0.25 km/s

B

0.5 km/s

C

1.0 km/s

D

2.0 km/s

Text Solution

Verified by Experts

The correct Answer is:
B
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Knowledge Check

  • The frequency of waves emitted from a radar is 750 MHz. The frequency of reflected wave from the aeroplane as observed at the radar station is increased by 2.5 KHz. What is the speed of aeroplane

    A
    `4 Kms^(-1)`
    B
    `2 Kms^(-1)`
    C
    `1 Kms^(-1)`
    D
    `0.5 Kms^(-1)`

  • When a laser beam returns after reflection from an aeroplane, the observed change in frequency is 1% , then the speed of the aeroplane is (c is the velocity of light)

    A
    `(c)/(50)`
    B
    `(c)/(100)`
    C
    `(c)/(200)`
    D
    `(c)/(2)`

  • When a train approaches a stationary observer, the apparent frequency of the whistle is n' and when the same train recedes away from the observer, the apparent frequency is n" . Then the apperent frquency n when the observer sitting in the train is :

    A
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    B
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    D
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