A uniform plane wave, impinging at normal incidence on the plane (x 1 = 0) of separation between two lossless dielectric media, conveys a power density of 1 mW/mm 2 . The power density of the...

A uniform plane wave, impinging at normal incidence on the plane (x₁
= 0) of separation between two lossless dielectric media, conveys a power density of 1 mW/mm². The power density of the transmitted wave is 3 dB below that of the incident wave. Find the modulus of the electric field of the reflected wave in the following two cases:

a) the medium in which the incident and the reflected waves travel is air;

 b) the medium in which the transmitted wave travels is air. Repeat the problem assuming that the incidence angle is π/4 and that the power densities on the x₁
= 0 plane remain the same as in the previous cases.