Every material has special features called properties. Properties tell us how a material looks, feels and behaves. We choose materials by their properties.
Common properties
- Hard or soft — a rock is hard, a sponge is soft.
- Waterproof or absorbent — plastic keeps water out, a towel soaks water up.
- Can float or sink — wood floats, a stone sinks.
- Lets light through or not — glass is clear, wood is not.
- Bends easily or stays stiff — rubber bends, metal stays stiff.
Key idea
The properties of a material decide what it can be used for. We match the material to the job.
Choosing the right material
A raincoat is made of plastic because plastic is waterproof, so it keeps us dry. A window is made of glass because glass lets light through, so we can see outside.
Example
A cooking pot is made of metal because metal is strong and does not melt with heat. A pillow is filled with soft material so it feels comfortable.
Remember
- One material can have many properties.
- We pick a material that fits what we need it to do.