JEE Main 2021PhysicsElectromagnetic WavesMediumMCQ

JEE Main 2021 — Electromagnetic Waves Question with Solution

JEE Main 2021 (26 Aug Shift 2)

Question

A light beam is described by E=800sinωt-xc. An electron is allowed to move normal to the propagation of light beam with a speed of 3×107 m s-1. What is the maximum magnetic force exerted on the electron?

Choose an option

Show full solutionCorrect option: B
Correct answer
B12.8×10-18 N

Step-by-step explanation

E0=800 V

B0=E0c=8003×108

Fm=qvB0=1.6×10-19×3×107×8003×108

=12.8×10-18 N

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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.