Question

What do we understand by the term point of incidence? What is called as the normal in the reflection of light from the plane mirror? Define the angle of incidence and also explain the angle of reflection.

Answer 1

Hint: The phenomenon or the process of sending back the light rays which have fallen on the surface of a body is known as reflection of light. Incident ray is a kind of ray of light that incidents on the mirror surface. The reflected ray or the ray of reflection is defined as the ray of light which is sent back by the mirror or the ray which gets reflected by the mirror. This will help you in answering this question.

Complete step by step answer:
 The phenomenon or the process of sending back the light rays which have fallen on the surface of a body is known as reflection of light. Incident ray is a kind of ray of light that incidents on the mirror surface. Point of Incidence will be the point at which the ray of incidence falls on the mirror. Now let us look at the parameter called as normal. The normal is a line which is at right angle to the mirror surface. This line is usually drawn at the point of incidence. The reflected ray or the ray of reflection is defined as the ray of light which is sent back by the mirror or the ray which gets reflected by the mirror. Angle of incidence is defined as the angle produced by the incident ray with the normal at the point of incidence. The angle of reflection is defined as the angle developed by the ray of reflection with the normal at the point of incidence. Therefore all the parameters have been explained.

Note: A plane mirror is defined as a mirror having a flat reflective surface. For the light rays which are striking a plane mirror, the angle of incidence will be equivalent to the angle of reflection. A plane mirror can always form a virtual image.