1. Conductors of Electricity
My Pals are Here! Science © 2008 Marshall Cavendish (Singapore) Private Limited
© 2009 Marshall Cavendish International (Singapore) Private Limited

2. Questions to think about…
What are electrical conductors and insulators?
Are good conductors of electricity also good conductors of heat?
How do we use electricity safely?
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3. What is electricity?
Electricity is conducted through some things better than others do.
Some materials are very resistant. Their atoms hold their electrons very tightly so they cannot move very well. These things are called insulators. (Can you give some examples?)
E.g. rubber, plastic, cloth, glass, dry air etc.
Some materials have loosely held electrons which move through them very easily. These are called
Conductors e.g. most metals like copper, aluminum, steel etc.

4. Conductors and insulators
Take a close look at this wire.
There is metal on the inside and plastic on the outside.
Why?
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5. Conductors and insulators
Some materials, like copper, allow an electric current to flow through them.
Such materials are called conductors of electricity.
Many other metals also conduct electricity well.
Hence, wires are usually made of metals.
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6. Conductors and insulators
Examples of metals that are conductors of electricity:
aluminium
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7. Conductors and insulators
Examples of metals that are conductors of electricity:
iron
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8. Conductors and insulators
Examples of metals that are conductors of electricity:
copper
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9. Conductors and insulators
Examples of metals that are conductors of electricity:
gold
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10. Conductors and insulators
Examples of metals that are conductors of electricity:
silver
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11. Conductors and insulators
To prevent the electric current from flowing out of a circuit, wires are coated with plastic.
Plastic does not allow an electric current to flow through it.
plastic
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12. Conductors and insulators
Other than plastic, many other materials do not allow an electric current to flow through them.
These materials are called non- conductors of electricity.
Non-conductors of electricity are also called insulators.
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13. Conductors and insulators
Examples of non-conductors of electricity:
paper
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14. Conductors and insulators
Examples of non-conductors of electricity:
rubber
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15. Conductors and insulators
Examples of non-conductors of electricity:
wood
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16. Conductors and insulators
Examples of non-conductors of electricity:
glass
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17. Conductors and insulators
Examples of non-conductors of electricity:
clay
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18. Using electricity safely
Electricity is useful but it can harm us if we do not use it carefully.
Other than getting a nasty shock, we can cause a fire if we do not use electricity carefully.
So what can we do to protect ourselves?
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19. Using electricity safely
Never try to repair any electrical equipment or electrical socket yourself.
Get an adult or an electrician who knows how to repair it.
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20. Using electricity safely
When repairing any electrical equipment, proper tools with plastic or wooden handles should be used.
Such materials are non- conductors of electricity.
They prevent electricity from flowing from the equipment to our hands.
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21. Using electricity safely
Ensure that there are no exposed wires in electrical equipment.
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22. Using electricity safely
Never touch switches or electrical equipment with wet hands.
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23. Using electricity safely
Do not put too many plugs into one socket.
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24. Using electricity safely
Use safety devices such as circuit breakers and fuses.
Sometimes, fires are accidentally caused when too much current flows through a circuit.
Circuit breakers and fuses break a circuit when too much current flows through them.
fuse
circuit breaker
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25. The end
My Pals are Here! Science © 2008 Marshall Cavendish (Singapore) Private Limited
© 2009 Marshall Cavendish International (Singapore) Private Limited