JEE Main 2020PhysicsElectromagnetic WavesEasyMCQ

JEE Main 2020 — Electromagnetic Waves Question with Solution

JEE Main 2020 (06 Sep Shift 2)

Question

For a plane electromagnetic wave, the magnetic field at a point x and time t is :

B→x, t=1.2×10−7sin0.5×103x+1.5×1011tk^ T.

The instantaneous electric field E→ corresponding to B→ is :

Choose an option

Show full solutionCorrect option: A
Correct answer
AE→x,t=-36 sin0.5×103x+1.5×1011tj^ Vm

Step-by-step explanation

E0=B0×C=1.2×10-7×3×108=36

As the light is propagating in x direction.

& E^×B^||C^

∴ E→ should be in j^ direction.

So electric field E→=E0sinE→·(x,t)=-36sin0.5×103x+1.5×1011tj^Vm

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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.