Answer Happy

5 The Fresnel reflection coefficients for p polarised light incident from air upon the surface of a non-magnetic material with refractive index n is given by Tp nt cos inį cos Ot ni cost+nt cos 0₂ Show that for the special case of incidence at Brewster's angle, 0, we have 0; = π/2-0t, and hence express B in terms of ni and nt. 16 State Snell's law. Hence show that all the light that reaches a scuba diver lying on the bottom of a shallow lake must pass through a circular region on the surface of the water. Illustrate your answer with a simple ray diagram. [5]