gcsescience.com                                       34                                       gcsescience.com

Electricity

Mains Electricity - Household Uses.

What is an Electrical Appliance?

An appliance contains a useful arrangement of
electrical components. There are a large number of
household appliances that use mains electricity. 
Appliances include cookers, heaters, lighting,
washing machines, fridges, dishwashers, freezers,
TV, computers, DVD, printers and music systems.

The first two, cookers and heaters, can be powered
by other types of energy, for example natural gas.
Lighting today is almost entirely powered by electricity
but in the past, gas lamps and candles were used.

Mains electricity has an alternating current
and this can be used directly to power cookers
and heaters. These work because of the
heating effect of current passing through a wire.

Computers, music systems, TV, DVD and
printers can only use direct current electricity.
The alternating current of mains electricity
must first be turned into direct current by using
an arrangement of diodes. Diodes allow the
current to flow in one direction only. The voltage
is often stepped down to 12 volts or less for
these appliances by using a suitable transformer.

     Links      Electricity      Mains      Revision Questions