Question

A ray of light is incident on a plane mirror at angle of 30°degree .what is the angle of reflection

Answer 1

The angle of reflection is 60 degrees. (Note that the angle of incidence is not 30 degrees; it is 60 degrees since the angle of incidence is measured between the incident ray and the normal.)

Answer 2

The complete question is:-

A ray of light is incident on a plane mirror at an angle of 30°degree with the mirror. what is the angle of reflection?

Answer:-

Given:

The angle between the incident ray and the mirror is 30°

To Find:

The angle of reflection

Solution:

When a ray of light falls on a plane mirror,

the angle of incidence = angle of reflection (Law of reflection)

Since the angle between the incident ray and the mirror is 30°,

Angle of incidence (i) = (90° - 30°) = 60° (As angle of incidence is calculated from the normal)

∠i = ∠r

⇒ ∠ r = 60°

Hence, the angle of reflection is 60°