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NTA Abhyas JEE Main2020PhysicsWaves and SoundPractice

A certain radar operates at a wavelength of 50 cm . If the beat frequency between the transmitted signal and the signal reflected from aircraft ∆ f = 1 kHz , then what will be the velocity (in km h - 1 ) of the aircraft?

Correct answer

900

Step-by-step solution

∆ f = f 2 v c = 2 v 1 λ ∴ v = λ ∆ f 2 = 0.5 × 1000 2 = 250   m   s - 1 = 900   k m / h r

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