Materials and their properties What are materials A

Materials and their properties.

What are materials? A material is a physical substance used to make things. Metals, plastics, ceramics, glass and fibres are some of the main categories for materials. If we look around, everything we see is made from a material, sometimes more than one. .

For example: � The clothes you are wearing are made from fibres. � The chair you are sitting on is made from plastic. � The windows in the school are made from glass. � � Can you see any other examples around you?

Properties of materials � A property of a material is a description of the characteristics which it has. They are adjectives which tell us about the material. � Materials have different properties and characteristics depending on what they are used for. � Some materials are hard, others are soft. Some are strong, others are weak.

List of properties � Here is a list of the properties which describe different materials: � Shiny – It reflects light � Strong – It won’t break easily � Flexible – It can be bent easily without breaking � Light - It doesn’t weigh much � Heavy – It weighs a lot � Coloured – Has colour � Magnetic – It’s attracted to magnets � Bendy - Flexible

� Hard – Something which can’t be bent easily � Brittle – It’s hard but will break easily � Malleable – It can be shaped easily � Magnetic – It’s attracted to magnets � Bendy – Flexible � Transparent – Something you can see through � Translucent – Something you can partially see through � Opaque – Something you can not see through � Conductor – It allows heat or electricity to pass through � Insulator – It doesn’t allow heat or electricity to pass through.

� Which of the previous words could you use to describe: � A) a pencil. . . � Hard, light, opaque � B) A window � Transparent or translucent, hard, brittle � C) A piece of paper. . . � Light, opaque, malleable � D) A fork. . . � Shiny, hard, magnetic, opaque, conductor

� Materials can be categorised into groups. One of the main groups is. . . Shiny Strong METALS Usually opaque E, g aluminium, copper, iron, lead. . . Good conductors of heat and electricity Some are magnetic

� These properties make metals suitable for many things. . . � � � Tools Bridges Coins � Knives, forks and spoons � Can you think of any other uses of metals?

Uses and properties. . � Q) Why is copper suitable for electrical wiring? What properties must it have? �- Good conductor of electricity - It is strong.

� Why are saucepans made from metal? Which properties make it suitable for the use? �- It is a good conductor or heat. �- It is It does not melt with high temperatures. �- It is strong