JEE Main 2017PhysicsElectromagnetic WavesMediumMCQ

JEE Main 2017Electromagnetic Waves Question with Solution

JEE Main 2017 (09 Apr Online)

Question

The electric field component of a monochromatic radiation is given by E=2E0coskzcosωt i^, Its magnetic field B is then given by:

Choose an option

Show full solutionCorrect option: A
Correct answer
A2E0csinkzsinωt j^

Step-by-step explanation

dEdz=-dBdt

dEdz=-2E0Ksinkzcosωt=-dBdt

dB=+2E0Ksinkzcosωt dt

B= +2E0Ksinkzcosωt dt

=+2E0kωsinkzsinωt

E0B0=ωk=C

B=2E0Csinkzsinωt

Propagation of EM radiation, Electric field oscillation and Magnetic field oscillation are perpendicular to each other.

Since propagation of EM radiation is x-axis and electric field oscillation is along z-axis, the Magnetic field oscillation is along y-axis.

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About this question

This is a previous-year question from JEE Main 2017, 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.