JEE Main 2021PhysicsElectromagnetic WavesEasyMCQ

JEE Main 2021 — Electromagnetic Waves Question with Solution

JEE Main 2021 (22 Jul Shift 1)

Question

Intensity of sunlight is observed as 0.092 Wm-2 at a point in free space. What will be the peak value of magnetic field at that point ? ε0=8.85×10-12 C2 N-1 m-2

Choose an option

Show full solutionCorrect option: A
Correct answer
A2.77×10-8 T

Step-by-step explanation

Iavg =B02C2μ0&1μ0=ϵ0C2
I=B022ϵ0C3
 B0=2Iϵ0C3
 B0=2.77×10-8 T

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About this question

This is a previous-year question from JEE Main 2021, 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.