(i) Define critical angle.
(ii) State one important factor which affects the critical angle of a given medium.
The diagram below shows a point source P inside a water container. Four rays A, B, C, D starting from the source P are shown up to the water surface
1) Show in the diagram the path of these rays after striking the water surface.
The Critical Angle for the water-air surface is 48°.
2) Name the phenomenon which the rays B and D exhibit.
A light ray is incident from a denser medium on the boundary separating it from a rarer mediuma an angle of incident equal to the critical angle, what is the angle of refraction for the ray?