Question

The following diagram shows an incident ray AO and the normal ON on a plane mirror. Find the angle of incidence and angle of reflection.

Answer 1

ON is perpendicular on a plane mirror Angle of incidence ∠i (∠AON) i.e. 

Angle between incident ray and normal ray = 90° – 30° = 60° 

Angle of Reflection = 60°

∴ ∠i = ∠r 

∴ Angle between incident and reflected ray i.e. ∠AOB 

= 60 + 60 = 120°