2. When light falls on a shiny surface, it bounces back this phenomenon is called reflection. We are able to see image in
mirror or in water because of reflection.
The process of sending back light rays fall which fall on the surface of an object is called reflection of light
4. The ray of light which strikes the surface is called incident ray
The ray which comes back after reflection is called reflected ray
The perpendicular line drawn at the point of incidence is called normal
The angle between the normal and incident ray is called angle of incidence(<I)
The angle between the normal and reflected ray is called angle of reflection (<r)
The angle of incidence is always equal to the angle of reflection.
5. Suppose you are in a dark room. Can you see
objects in the room ? Can you see object
outside the room ?
6. The relation between the incident ray, the reflected ray and the normal is given as the laws of reflection
The laws of reflection are as follows :
The incident ray, the reflected ray and the normal at the point of incidence , all lie in the Same plane.
The angle of incidence(<I) is equal to the angle of reflection (<r)
7. When we see ourselves in a mirror, it appears that our image is actually behind the mirror. This is
illustrated in Figure. We see the light coming from a direction determined by the law of reflection.
The angles are such that our image is exactly the same distance behind the mirror as we stand away
from the mirror. If the mirror is on the wall of a room, the images in it are all behind the mirror.
8. Take a white sheet of paper and place it on the table
Let the sheet be a little outside the edge of the table
Take a comb and close all its opening except the middle
Hold the comb perpendicular to the sheet of paper
Now through light of the torch from through the opening of the comb
We can see the incident and the reflected ray on the white sheet
Now we make the normal
Using a scale , we cut the sheet from point of incidence
We can see that incident ray, reflected ray and normal lie on the chart paper. They are not up or below the
chart paper
Hence, incident, reflected and normal all lie in the same plane
9. •Explain what is reflection of light ?
•What is incident ray ?
•What is angle of incidence ?
•What are the laws of reflection ?
•Describe an activity to show reflected ray, incident ray and the normal at the
point of incidence
•What is the first law of reflection
•What makes thing visible ?
