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Materials

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Origin of materials

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Natural origin

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They come directly from nature.

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For example, wool, wood, cotton, gold, etc.

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Artificial origin

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They are made from natural materials.

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For example, paper, glass, plastic or steel.

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Properties of materials.

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Each material has its own characteristics and properties.

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We can perceive some properties through our senses.

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For example, the smell, the texture, the taste or the color.

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To perceive other properties we have to experiment.

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Hardness. It is the resistance to scratching. Materials can be hard or soft.

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For example, diamonds and bronze are the hardest ones.

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Conductivity. It is the material's ability to transfer electricity or heat.

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A material can be conductive. It lets electricity or heat pass on, for example, iron.

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Non-conductive. It does not let electricity or heat pass on, for example, plastic.

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Thermal insulation.

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The material reduces the transfer of heat, for example, glass.

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Acoustic insulation. It is the material's ability to let sound pass through.

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We use these materials to reduce noise, for example in houses.

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Waterproof. These materials do not let water go through. For example, rubber or plastic.

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Light transmission. It is the property of allowing light to go through.

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Materials can be transparent. It lets the 100% of light go through and you can see what is on the other side. For example, glass.

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Translucent. It lets part of the light pass through but you cannot perfectly see the other side. For example, plastic.

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Opaque. It does not let fly, throw and you cannot see this other side. For example, stone.

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Flexibility. It is the capacity of a material to be folded or bent.

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Materials can be flexible. It can be easily folded. For example, paper.

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Rigid. It cannot be folded or bent. For example, wood.

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Elasticity. It is the material's capacity to be deformed and to recover its original form.

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Materials can be elastic. It can be deformed and recover its original form easily. For example, rubber.

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Non-elastic. It cannot be deformed, for example, a stone.

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Magnetism. It is the property of attraction between magnets and metal.

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Materials can be magnetic. They attract each other easily, for example, metal.

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Non-magnetic. They do not attract each other, for example, wood.