JEE Main 2020PhysicsElectromagnetic WavesMediumMCQ

JEE Main 2020 — Electromagnetic Waves Question with Solution

JEE Main 2020 (03 Sep Shift 2)

Question

The electric field of a plane electromagnetic wave propagating along the x direction in vacuum is E→=E0jcos(ωt-kx). The magnetic field B→, at the moment t=0 is:
 

Choose an option

Show full solutionCorrect option: C
Correct answer
CB→=E0μ0ε0cos(kx)k^

Step-by-step explanation

B0=E0C=E01/μ0ε0=E0μ0ε0

As the light is propagating in x direction

and E^×B^ || C^

∴ B→ should be in K^ direction

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About this question

This is a previous-year question from JEE Main 2020, 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.