Question

An incident ray of light is initially normal to the surface of the plane mirror. The mirror is rotated until the angle between the incident and reflected rays is 30° the mirror has been rotated through an angle of.The mirror has been rotated through an angle of

1)7.5°
2)15°
3)30°
4)45°​

Answer 1

Answer:

2) 15°

Explanation:

Firstly, the incident ray is normal to the surface of the plane mirror but when the mirror was rotated , the angle betw incident and the reflected ray is 30°.

we know that the angle of incidence= angle of reflection. so 30°=2 angles ..hence angle of incidence/reflection=15°. therefore the mirror was rotated 15°.