Question

What is the average energy density of an electromagnetic wave?

Answer 1

Dear student

energy density of electromagnetic wave in an Electric field is $U_E=\frac{1}{2}{\epsilon }_0{E}^2$
And Energy density of electromagnetic wave in magnetic field is $U_B=\frac{{\displaystyle \frac{1}{2}}{B}^2}{{\mu }_0}$

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