28/09/09

Conductors and insulators

Conductors: a substance which allows electricity to flow throught it . f .ex opper are used to carry current , electric current is carried round your home by copper wires iron ,silver , tin , aluminium , gold ,mercury and caron are conductors.

Insulators : a substance which does not allow electricity to flow through it .insulators are used for safety .the electricity used in your home can be dangerous you could easily be killed if you touched a bare wire that is why plugs and wires are covered with insulators like : rubber , plastic , wood , wool , paper ,glass ,string ,nylon etc ...

Making the right connections

The quiz board

The railway signal

When a battery is working ,the energy change is

Chemical energy to electrical energy

The battery’s chemical energy is used up pushing a current round the circuit the ‘ electrical push ‘ which the batlery gives to the current is called the voltage .it is measured in volts (v) on a volt –meter.

Diffent batteries produce different voltages .the bigger voltage supplied by the battery the bigger will be the current that plows in a circuit.