A ray of light incident at 25° on one refracting surface of a prism of angle 60° suffers a deviation of 50°. What will be the angle of emergence?

85°

The correct answer is Option (1) → 85°

Given:

Angle of incidence: $i = 25^\circ$

Prism angle: $A = 60^\circ$

Deviation: $\delta = 50^\circ$

Relation between deviation, prism angle, and angles of incidence and emergence:

$\delta = i + e - A \Rightarrow e = \delta + A - i$

Substitute values:

$e = 50 + 60 - 25 = 85^\circ$

∴ Angle of emergence = 85°