Page 49 - Science Class 06

Similarly, fill a glass with water. If you v Materials have concrete bodies and can
pour more water into it, the water will
spill over the brim and fall to the
ground.
Liquids take the shape of the container
in which they are kept.
Gases cannot be easily seen. But every
empty vessel is full of air. Let us examine
this fact. Take a bucket and fill it half with
water. Now, take empty glass. Invert it
straight into the water and try to push it
down. It will not go down. Why? Because it
is full of air and there is no space for water
in it. But if you lt it to one side the air in it
will escape in the form of bubbles and
water will start ge ng it.
Similarly, when we blow into an empty
balloon, it gets puffed up to show that the
air of the breath has taken up the space
inside the balloon.
Sor ng Materials into Groups
v All objects around us are made of one or more materials.
v Materials are sorted into groups based on their proper es.
The material used to make an object depends e.g., tumbler used for storing water is
on:
v proper es of the material.
v purpose of which the object will be used.
Science-6
be touched. As all solids have bodies,
we can touch any solid-stone. Sugar, ice,
etc. are known whether it is hard,
crumbly or smooth.
Again we can touch any liquid and feel
that it has a body. Water, milk, oil,
honey all have bodies that can be
touched.
As for gases, air etc. we know that we
feel it when it blows, though we cannot
see it because it has no colour. The
touch of the air feels very soothing
when it is hot and stuffy. Fans are used
for this purpose because they make the
s ll air into mo on and reach us.
v Materials have weight. Take any hard
substance (solid) and weigh it in a
balance to find out its weight. Similarly,
a liquid can be weighed a er pu ng it
into a container of known weight. Thus
its own weight can be found out. As for
gases, we can know the weight of the air
in a puffed up balloon a er weighing it
against an empty balloon. It will be
heavier showing thereby that air has
weight. A used up gas cylinder is lighter
than a newly filled one. What is this
weight of different materials due to? It
is due to the mass that they have. Mass
is amount of something has been
named ma er.
made of glass, metal or plas c.
It cannot be made up of cloth or
paper.
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