Question

In a prism, is angle of incidence always equal to angle of emergence?

Answer 1

The angle of minimum deviation is attained when the angle of incidence and angle of emergence for a ray of light being refracted through a prism, are equal. Where, is the angle of deviation at an arbitrary angle of incidence , and is the refractive index of the prism.


angle of incidence is not equal to angle of emergence in glass prism. but in case of minimum diviation , they are equal.

ang. of incidence + angle of emergence= angle of deviation + angle of the prism