A plane light wave in the visible region is moving along the Z-direction. The frequency of the wave is` 0.5×10^(15)` Hz and the electric field at any point is varying sinusoidally with time with an amplitude of 1V/m. Calculate the energy densities of the electric and magnetic fields.

Explanation

Total average energy density (due to both electric and magnetic fields)
`=1/2in_(0)E_(0)^(2)(8.85×10^(–12)) (1)^(2) = 4.42×10^(–12) J//m^(3)`
Since the energy is shared equally by the electric and magnetic fields, average energy density of the electric field
`=1/2(4.42×10^(–12) J//m^(3)) = 2.21×10^(–12) J//m^(3\)`
`=1/2(4.42×10^(12) J//m^(3)) = 2.21×10^(–12) J//m^(3)`