Question

A mirror is tilted at an angle of 35 degrees to the bench. A ray of light is directed so that it hits the mirror at an angle of 45 degrees to the surface of the mirror as shown. What is the angle of reflection?

Answer 1

By first law reflection, angle of incidence is equal to angle of reflection.

Angle of incidence is angle between incident ray and normal ( perpendicular to surface) at the point of incidence. Similarly angle of reflection is angle between reflected ray and normal at point of incidence.

As incident ray makes angle of 45 degree with surface and normal makes angle of 90 degree with surface, angle between incident ray and normal or angle of incidence

= 90 - 45 = 45 degree

Hence angle of reflection =45 degree