Page 134 - Active Science 5 Ebook and Activity

Non-luminous objects are made of various kinds of substances. Different objects allow
different amount of light to pass through them and are classified according to the same.

Activity 12.1

Aim : Identifying different kinds of materials on the basis of the amount of

light they allow to pass through.

Materials Required: A clear laminating sheet, a waxed paper and a cardboard.

Procedure : • Take a clear laminating sheet, a waxed paper and a cardboard.

• Now try to see through these objects.

Observation : You will observe that you can easily see through the clear laminating
sheet, partially through waxed paper and not be able to see through
cardboard.

Laminating Sheet Waxed Paper Cardboard

T ransparent Objects

The objects through which light can pass completely are called transparent objects.
We can easily see through them. Examples of such objects are plastic cover, glass, clear

water, lenses and air.
Factual Study
What do you think about a mirror?
Is it a transparent material? No, it is
not a transparent material because
Lens we cannot see objects on the other
Clear Water side of the mirror. We can only see
Plastic cover our own image in the mirror.

Let’s Recapitulate

Tick the correct statements.

1. Those objects which produce their own light are called non-luminous objects. _____
2. Different materials allow different amount of light to pass through them. _____

3. Stars are luminous objects. _____
4. Air allows light to completely pass through it. _____

134 Active Science-5