Page 131 - Innovator's Science-8

Uses of Spherical Mirrors

Concave mirrors are useful in the following ways:
• They are used by dentists to see enlarged images of the teeth.

• They are used in make-up and shaving mirrors.

• They are used as reflectors in the torches and headlights of automobiles.
• They are used by doctors to examine ear, nose, throat and eyes.

Convex mirrors are used as rear view or side mirrors in cars and scooters.
This is because they can view a much larger area than a plane mirror.

Science
Bytes

Testimony
The amount of light that a. Dental check up b. A side view mirror c. Headlights of a car
is reflected from a surface using a concave mirror (convex) of a vehicle (concave mirror)
depends on material, and
Uses of spherical mirrors
nature of the surface.
Reflection of Light

The bouncing back of light from the surface of an object is called reflection
of light.
When we stand in front of a mirror or a shiny metal surface, we can see not

only our image, but the images of all things around us. This happens
because the mirror or the metal surface reflects light coming from all
objects.

Let us understand this with the help of a diagram.
Reflection of light
• In figure, ON is the normal. Normal is a line perpendicular

to the surface of the mirror at the point of incidence (O).
• The ray of light coming from and object that falls on the

surface of the mirror is called incident ray . In the given
figure OA and OB are the incident rays.
• The ray of light that gets reflected from the mirror is called

reflected ray. In the alongside figure OB are the reflected rays.

• The angle formed by the incident ray with the normal is
called the angle of incidence . The two angles of incidence
in the alongside figure are i and r.

• Angle of reflection is the angle formed between the reflected
Reflection of light from ray and the normal i and r are the angles of reflection.
a plane mirror.

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Science-8