In an E.M. wave,the average energy density is | vedclass

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(C) The energy density due to the electric field is given by $u_E = \frac{1}{2} \epsilon_0 E^2$.The energy density due to the magnetic field is given

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electric and magnetic fields equally

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(C) The energy density due to the electric field is given by $u_E = \frac{1}{2} \epsilon_0 E^2$.The energy density due to the magnetic field is given by $u_B = \frac{1}{2} \frac{B^2}{\mu_0}$.In an electromagnetic wave,the relationship between the electric field $E$ and magnetic field $B$ is $E = cB$,where $c = \frac{1}{\sqrt{\mu_0 \epsilon_0}}$.Substituting $B = \frac{E}{c}$ into the magnetic energy density formula,we get $u_B = \frac{1}{2} \frac{(E/c)^2}{\mu_0} = \frac{1}{2} \frac{E^2}{c^2 \mu_0} = \frac{1}{2} \epsilon_0 E^2 = u_E$.Thus,the average energy density is equally contributed to by both the electric and magnetic fields.

In an $E.M.$ wave,the average energy density is associated with

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