JEE Main 2024PhysicsElectromagnetic WavesMediumMCQ

JEE Main 2024 — Electromagnetic Waves Question with Solution

JEE Main 2024 (31 Jan Shift 1)

Question

In a plane EM wave, the electric field oscillates sinusoidally at a frequency of 5×1010 Hz and an amplitude of 50 V m–1. The total average energy density of the electromagnetic field of the wave is : [Use ε0=8.85×10–12 C2 N-1 m-2]

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Show full solutionCorrect option: A
Correct answer
A1.106×10–8 J m–3

Step-by-step explanation

Total average energy density of the electromagnetic field is given by, UE=12ε0E02.

⇒UE=12×8.85×10-12×502

=1.106×10–8 J m–3

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About this question

This is a previous-year question from JEE Main 2024, 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.