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Home > Physics > Using electricity > From the wall socket


From the wall socket

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This bite deals with the safe use of electricity in the home.

WARNING: The mains supply can be dangerous if it is not treated properly.DO NOT INTERFERE WITH THE MAINS SUPPLY OR ANY APPLIANCES AT HOME.

This bite includes the subjects household appliances and the earth wire.

Work through them all or go to the ones that interest you. You may wish to print a hard copy for your reference.

Household appliances

The mains supply is used as the source of electrical energy for all types of household appliances. Here are some of the facts you should know:

  • In all electrical appliances, electrical energy is transferred into other forms. For example:

ApplianceElectrical energy transferred to
hair dryerkinetic and heat
  • In general, the appliances that transfer electrical energy into heat are the appliances with the highest power ratings.
  • Appliances are connected to the mains supply by means of a flexible cable, more often called a flex. The size and type of flex used must suit the type of appliance. Appliances with higher power ratings need flexes with larger diameter wires in them.
  • The flex of an appliance is usually connected to the mains with a 3-pin plug.You need to know the wires that are connected to each pin in a plug, and the colours of insulation used for each of the three wires live, neutral and earth.
Wiring a plug - showing the earth, neutral and live wires as well as the fude, cable grip and outer insulation

Wiring a plug

The colours of insulation used for the wires in a flex are:

  • Live wire - brown
  • Neutral wire - blue
  • Earth wire - green/yellow stripes

Its easy to remember which wire is connected to each pin in a plug.

As you look at a plug the way it would be inserted:

  • The BRown covered wire goes to the Bottom Right pin
  • The BLue covered wire goes to the Bottom Left pin
  • The striped wire goes to the only pin that remains.

We've even got a short animation which can help you to remember this:


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A still from an animation about the dangers of mains electricity.

Class Clips

Video clip about the dangers of mains electricity

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