Q.

An unpolarized light is incident on the plane interface of air-dielectric medium shown in figure. If the incident angle is equal to Brewster angle, identify the expression representing reflected wave.                 [2026]

1 (Exi^+Eyj^)sin(kx-kz-ωt)  
2 (Exi^+Ezk^)sin(kx+ky-ωt)  
3 (Exj^+Eyk^)sin(ky+kz-ωt)  
4 (Exi^+Eyj^+Ezk^)sin(kx+ky-kz-ωt)  

Ans.

(1)

The incident wave travels forward (+x) and down (+z). Upon reflecting off the horizontal xy-plane, it bounces back up. It now travels in the +x and -z directions. This corresponds to the phase term sin (kx-kz-ωt), which is only present in Option (1).