THE THREE PIN PLUG
1.Collect a diagram of the three pin plug which has been
provided.
2.Stick it into your notebook.
Information :- the earth is for safety .The fuse is for safety,
and the switch is for safety.The electricity flows FROM the
LIVE wire and BACK via the NEUTRAL
3.You will be shown how to wire the plug by your teacher.
Slide 33
energy
electrical safety in the house
THE THREE PIN PLUG CONT`D
THE FUSE
A fuse is a thin piece of wire which will melt if too much
current flows through it.If more than 3 amperes flows through
a 3 ampere fuse it will melt and will cause all the electricity to
be switched off.This means that the plug wires cannot overheat
and cause a fire.Fuses are of two types in a three pin plug.
If an appliance uses more than 3 amperes(3A) then a 13 ampere
fuse must be used.If it uses less than 3A then a 3A fuse is used.
INFORMATION
Slide 34
ELECTRICAL ENERGY
Fuses.
We generally have two types of fuse , the 3Amp and the 13 Amp.
The fuse is a safety device in the three pin plug.
If the power of an appliance is greater than 700Watts , e.g. a kettle , we use a 13Amp fuse.If it is less than 700 Watts , e.g. a lamp , we fit a 3Amp fuse.
Slide 35
energy
electrical safety in the house
INFORMATION THE EARTH WIRE
Normally the earth does nothing in a circuit, but if the live wire
somehow touches the casing of an appliance such as a toaster,
You would get an electric shock and be badly injured.To stop this
happening,the earth wire causes a large current to flow.This
blows the fuse and the appliance becomes dead.
Slide 36
NON RENEWABLE SOURCES OF ENERGY
The Fossil Fuels.
These are coal , oil and gas.
Coal is made from dead plant material milloins of years old.
Oil and Gas are made from dead sea creatures millons of years old.
Once they have been used they can no longer be used and are therefore running out.
Slide 37
CRUDE OIL
Crude oil is a mixture of hundreds of different compounds and is difficult to burn.
It is taken from the worlds oil fields to refineries where it is cleaned.
It is separated into different chemicals we can use.
Each different chemical is separated out at a different temperature.
Slide 38
CRUDE OIL
Crude oil products include the following ,
Bottled gas at 200C.
Petrol at 700C for vehicles.