Aquila Children's Magazine The Electric Issue | Page 5

For the current to flow, it needs a circuit.
This is an unending loop of conducting
material, so the electron can be passed
from one atom to the next. We add
appliances into the circuit to make them
work, these include everything from
games consoles to washing machines.
Cable grip
Neutral terminal
Earth terminal
Live terminal
Fuse
Let’s take a look at electricity in the
home. Remember that electricity can be
VERY dangerous, so don’t put anything
into the socket or take anything apart.
You could get a nasty shock.
The outside of a wall socket is mostly
made of plastic, which is a good
insulator. The plastic covering reduces
your chance of getting an electric shock.
Inside the socket are metal contacts,
which are supplied by the mains
electricity supply. You can usually see
them by looking at where the top pin of
the plug goes in. Remember not to
touch! In modern socket covers, the
lower two (and most dangerous) holes
are covered by protective shutters.
These open automatically when the top
pin of the plug is inserted.
A plug also has an insulating plastic case.
The metal pins are usually made of brass
(a good conductor) and these touch the
metal contacts inside the wall socket.
Your plug may have black insulation on
the pins, this is to reduce the chance of
touching a live pin when plugging in.
When you plug something in, the
electrical current flows from the mains
to the socket and then to the pins of the
plug. It travels through the internal
circuit of the appliance before going
back to the wall socket again. This makes
a circuit.
Each pin of the plug has a wire
connected to it, the live or line (brown)
wire has a fuse between the wire and
the pin, this breaks the circuit if too
much current flows. It protects you, the
circuit and the appliance. The live wire
carries the current from the mains
supply into the appliance and the
neutral (blue) wire completes the
circuit, carrying the current away from
the appliance back to the mains. The
earth (green-yellow) wire is there for
safety. It creates a safe route for the
current to flow through if the live wire
touches the casing, and stops you from
getting an electric shock.
Many modern plugs are completely
sealed units, but older plugs can safely
have the cover removed with the help of
an adult, so long as they are unplugged
from the wall. If you are looking at a UK
plug, the insides will look similar to the
diagram but the wires might be different
colours. Wires made before 2004 had
red insulation on live wires and black
insulation on neutral wires. Plugs from
different countries vary a little, but you
can easily find labelled diagrams of them
online.
Electricity can be very dangerous. If it
flows through your body it can disturb
the electrical messages in your muscles,
especially your heart. It will change the
rhythm of your heart or maybe stop it
altogether.
So how are birds able to sit on electricity
cables? It’s because electricity will
always take the easiest route – usually
along a nicely conductive wire. The
current would need to take a diversion
through a less conductive path to get
through the bird, so the electricity stays
in the wire. If the bird was able to flap its
wings and touch another electric wire
with a different voltage, then it would
likely get frazzled, as the bird has
become a path for the electricity to
reach a place of different voltage. This is
why electricity cables are usually high
off the ground and with plenty of space
between the wires!
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