Q42. (i) A ray PQ of light is incident on the face AB of a glass prism ABC (as shown in the figure ) and emerges out of the face AC. Trace the path of the ray. Show that
i + e = A +
where, and e denote the angle of deviation and angle of emergence, respectively.
Plot a graph showing the variation of the angle of deviation as a function of angle of incidence. State the condition under which is minimum.