Easy MCQ +4 / -1 PYQ · JEE Mains 2023

The energy density associated with electric field $\vec{E}$ and magnetic field $\vec{B}$ of an electromagnetic wave in free space is given by $\left(\epsilon_{0}-\right.$ permittivity of free space, $\mu_{0}-$ permeability of free space)

  1. A $U_{E}=\frac{\epsilon_{0} E^{2}}{2}, U_{B}=\frac{B^{2}}{2 \mu_{0}}$ Correct answer
  2. B $U_{E}=\frac{E^{2}}{2 \epsilon_{0}}, U_{B}=\frac{\mu_{0} B^{2}}{2}$
  3. C $U_{E}=\frac{\epsilon_{0} E^{2}}{2}, U_{B}=\frac{\mu_{0} B^{2}}{2}$
  4. D $U_{E}=\frac{E^{2}}{2 \epsilon_{0}}, U_{B}=\frac{B^{2}}{2 \mu_{0}}$

Solution

<p>The energy density associated with the electric field $\vec{E}$ and magnetic field $\vec{B}$ of an electromagnetic wave in free space is given by:</p> <p>For the electric field: $U_{E} = \frac{1}{2} \epsilon_{0} E^2$</p> <p>For the magnetic field: $U_{B} = \frac{1}{2} \frac{B^2}{\mu_{0}}$</p> <p>These expressions match Option A:</p> <p>$U_{E} = \frac{\epsilon</em>{0} E^{2}}{2}, U_{B} = \frac{B^{2}}{2 \mu</em>{0}}$</p>

About this question

Subject: Physics · Chapter: Electromagnetic Waves · Topic: Maxwell's Equations

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