A ray OA is incident upon a smooth surface POQ. It is reflected back along OB. A normal ON is drawn perpendicular to the surface at O (the point of incidence). The value of ∠AOP is60∘. Find the value of the angle of reflection.
∠AOP+∠AON=90∘ (as ON is perpendicular to POQ)
⇒∠AON=90∘−60∘ (as ∠AOP=60∘ )
Now, ∠AON=angle of incidence = angle of reflection=∠BON
Thus, angle of reflection =30∘