JAMB - Physics (2001 - No. 9)
A ray of light strikes a plane mirror at an angle of incidence of 35°. If the mirror is rotated through 10°, through what angle is the reflected ray rotated?
70°
45°
25°
20°
Explication
When ever a ray of light is incident on a plane mirror at an angle of incidence l, if the mirror is then rotated through an angle θ, then the reflected ray is rotated through an angle twice θ
So if θ = 35°, then the reflected ray is rotated through 2 x 10o = 20°
So if θ = 35°, then the reflected ray is rotated through 2 x 10o = 20°