You must use the right materials to make objects.
To choose the right material for an object, you must
• know what the object is used for
• know what properties the object must have
• nd out what materials have these properties
Materials such as rubber, wood and paper are obtained from plants.
Glass is made from a special type of sand called silica sand.
Dierent materials have dierent properties.
Wood, metal and some plastics are hard materials used to make objects
such as chairs and tables.
Paper is a soft material used to make objects such as books, copy books, newspapers
and gift wrappings.
Glass is a transparent material used to make window panes, bottles and glasses.
Plastic, metal and glass are impermeable materials. They are used to make objects
that can hold water. They are also used to protect us from rain.
Permeable materials allow water to pass through. For example, cotton cloth and
paper are permeable.
We must use the right materials to make objects.
If we choose the wrong materials to make objects, we will not be able to use
them properly.
What I have learnt
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