JEE Main 2018PhysicsElectromagnetic WavesMediumMCQ

JEE Main 2018 — Electromagnetic Waves Question with Solution

JEE Main 2018 (16 Apr Online)

Question

A plane electromagnetic wave of wavelength λ has an intensity I. It is propagating along the positive Y-direction. The allowed expressions for the electric and magnetic fields are given by:

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Show full solutionCorrect option: A
Correct answer
AE→= 2 Iε0c cos2πλy-ctk^,

B→=+1cEi^

Step-by-step explanation

If E0 is the amplitude of the electric field then the intensity of the electromagnetic wave is given as I=12ε0E02×c. From the above relation, we get E0= 2 Ic ε0. The relation between electric and magnetic fields is B0= E0c. The direction of E → × B → will be along +j^.

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About this question

This is a previous-year question from JEE Main 2018, 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.