A ray of light strikes a flat plane mirror surface such that the angle between the light ray and the mirror…
A ray of light strikes a flat plane mirror surface such that the angle between the light ray and the mirror surface is $30^\circ$. What is the angle of reflection measured from the normal?
$30^\circ$
$60^\circ$
$90^\circ$
$120^\circ$
Solution
The normal is perpendicular ($90^\circ$) to the surface. Angle of incidence $= 90^\circ - 30^\circ = 60^\circ$. According to laws of reflection, angle of reflection $= 60^\circ$.