Question

The light ray which strikes any polished surface at some angle is called
(A) Reflected ray
(B) Incident ray
(C) Normal ray
(D) None of these

Answer 1

Hint
There are many types of rays in optics. The main ones are the incident ray (the ray that incidents on any surface), the reflected ray (the ray that gets reflected from any surface) and the refracted ray (the ray that transmits through a surface).

Complete step by step answer
A light ray is either a straight or curved line that is perpendicular to the light’s wavefronts. Through an optical system, the rays are used to model the propagation of light. As the name implies, a ray that incidents on or strikes the polished surface at some angle is called the incident ray.
A ray diagram representing the different types of the ray is as follows:

$\therefore$ The light ray which strikes any polished surface at some angle other than ${\text{90}}^\circ$ is called the incident ray of light.
So the correct answer will be option (B).

Additional Information
The rays are characterized by their interaction with the surfaces.
-An incident ray is a ray of light that strikes any surface. The angle between the incident ray and the normal (the perpendicular) to the surface is called the angle of incidence.
The reflected ray is a ray of light that gets reflected when an incident ray strikes any surface. The angle between the reflected ray and the normal (the perpendicular) to the surface is called the angle of reflection.
-The refracted ray of the transmitted ray is a ray of light that is transmitted through the surface when an incident ray strikes any surface. The angle between the refracted ray and the normal (the perpendicular) to the surface is called the angle of refraction.

Note
The different types of the rays are differentiated by the angle that they make with the normal when they hit any surface. For any smooth surface, the angle of incidence will be equal to the angle of refraction.