Question

A point source is placed at a depth h below the surface of water (refractive index = μ). (a) Show that light escapes through a circular area on the water surface with its centre directly above the point source. (b) Find the angle subtended by a radius of the area on the source.

Answer 1

So, light escapes through a circular area on the water surface directly above the point source.
b) Anglesubtained by a radius of the area on the source, C = sin ^-1(1/μ).