Question

If a ray of light is incident at an angle of $60°$ to the normal, then the angle formed by the reflected ray with the normal is equal to_______.

Answer 1

Angle of incidence:

The angle of incidence is the angle between the direction of motion of the wave and a line drawn perpendicular to the reflecting boundary.

Angle of reflection:

The angle between the reflected ray and the normal at the point of incidence to a reflecting surface is known as the angle of reflection.

Determine the angle formed by the reflected ray with the normal:

1. According to the law of reflection, the angle that an incident light ray makes to the normal and the angle that it makes when it is reflected on a smooth surface must be equal.
2. Draw the direction of incident ray and reflected ray.
3. Therefore, if the incident ray and the normal ray are at a $60°$ angle, the reflected ray will be at a$60°$ angle as well.
4. Additionally, according to the law of reflection, the incident ray, the normal ray, and the reflected ray all reside on the same plane, the laws of reflection are not obeyed and the incidence angle and the reflection angle are not equal if an incident ray falls on an uneven surface.

Hence, If a ray of light is incident at an angle of $60°$ to the normal, then the angle formed by the reflected ray with the normal is equal to $60°$.