Question

A ray of light incident at an angle of incidence $i_1$ passes through an equilateral glass prism such that the refracted ray inside the prism is parallel to its base and emerges at an angle of emergence$i_2$. (i) How is the angle of emergence '$i_2$' related to the angle of incidence '$i_1$'? (ii) What can you say about the angle of deviation in such a situation?

Answer 1

(i) $i_2$ = $i_2$
(ii) Angle of deviation is minimum
In minimum deviation position, the refracted ray inside the prism travels parallel to it if the prism is equilateral and the angle of incidence is equal to the angle of emergence.