JEE Main 2019PhysicsElectromagnetic WavesDisplacement Current And Properties Of Em WavesmediumMCQ

JEE Main 2019Electromagnetic Waves Question with Solution

From: JEE Main 2019 (Online) 12th April Evening Slot

Question

A plane electromagnetic wave having a frequency v = 23.9 GHz propagates along the positive z-direction in free space. The peak value of the Electric Field is 60 V/m. Which among the following is the acceptable magnetic field component in the electromagnetic wave ?

Choose an option

Show full solutionCorrect option: D
Correct answer
D = 2 × 10–7 sin(0.5 × 103 z - 1.5 × 1011t)

Step-by-step explanation

Since the wave is propagating in positive z-direction

So acceptable magnetic field component will be



C =

= = 2 10-7

and = 223.9109 = 1.5 × 1011 Hz

and k = = = 0.5 × 103

Note : When wave is propagating in positive z-direction then sign of kz and should be opposite.
From option you can see only option D can be correct.

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About this question

This is a previous-year question from JEE Main 2019, covering the Electromagnetic Waves 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.