Electromagnetic Waves

JEE Main level, single correct, medium

135 of 165

Question 135 of 165

The rms value of the electric field of the light coming from the Sun is 720 N/C720 \mathrm{~N} / \mathrm{C}. The average total energy density of the electromagnetic wave is

Show answer and solution

Answer: (B) 4.58×10−6 J/m34.58 \times 10^{-6} \mathrm{~J} / \mathrm{m}^3

Uav=ε0Ers 2=4.58×10−6 J/m3U_{a v}=\varepsilon_0 E_{\text {rs }}^2=4.58 \times 10^{-6} \mathrm{~J} / \mathrm{m}^3
Erms =4.58×10−6 J/m3E_{\text {rms }}=4.58 \times 10^{-6} \mathrm{~J} / \mathrm{m}^3

JEE Main question paper PDF

Open a shift to read the full paper on this page, or download it.

JEE Main 2025 Apr 2 Shift 1 question paper

Open Download PDF

Opening paper…

Explain it as a whiteboard videoStep-by-step, in Hinglish or English. Your first video needs no login.Solved it on paper but got it wrong?Upload a photo of your working. Mistake Doctor marks the exact line that broke.

More Physics practice

JEE Main Physics practice question on Electromagnetic Waves (Electromagnetic Waves and Maxwell's equations), with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.