JEE Main 2017PhysicsWaves and SoundMediumMCQ

JEE Main 2017 — Waves and Sound Question with Solution

JEE Main 2017 (02 Apr)

Question

An observer is moving with half the speed of light towards a stationary microwave source emitting waves at frequency 10 GHz. What is the frequency of the microwave measured by the observer? (speed of light =3×108 m s-1)

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Show full solutionCorrect option: D
Correct answer
D17.3 GHz

Step-by-step explanation

cf′=cf 1-β1+β , β=vcβ=12

⇒1f′=1f1-121+12= 131f

⇒f′= 3f

⇒f′=1.7310

⇒f′=17.3 GHz

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About this question

This is a previous-year question from JEE Main 2017, covering the Waves and Sound chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.