P2.6

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alterenating current lows one way and then the opposite in successice cycles. THE FREQUENCY is the number of cycles it passes through each second.

THE MAINS FREQUENCY IN THE UK IS 50hz.

every mains circuit has a live wire and a neutral wire. It alternates between the two wires. Neutral wire is earthed at the local sub station whereas, the live wire is dangerous because it reaches 300 v in each direction.

The earth wire is connected to the ground of your home.

the longest pin of a three pin plug is designed to make contact with the earth wire to make it automatically earthed.

Cables have two or three wires insulated copper wires surrounded by flexible plastic material.

THE BROWN WIRE IS LIVE AND CONNECTED TO THE LIVE PIN.

THE BLUE WIRE IS CONNECTED TO THE NEUTRAL PIN

THE GREEN AND YELLOW PIN IS CONNECTED TO THE EARTH PIN. A TWO CORE CABLE DOESNT HAVE A EARTH WIRE. I.E HAIR DRYERS AND RADIOS.

a fuse contains a thin wire that heats up and melts if too much current passes through it.

A fuse must always have the correct current running through it

A circuit breaker is an electromagnetic switch that opens and cuts the current off if to much current passes through it.

alternanting current.

cables and plugs

FUSE