3 of 7 lessons
Conductors and insulators
What you’ll learn about
Conductors
Conductors are materials that carry electric current really well.
Metals like copper are good conductors - that's why they're used to carry the electricity in wires and electricity wires.
Electricity always tries to find a path for itself to reach the ground - and it will travel through any conductors it can find to get there - taking whatever shortcuts it can.
Water is a really good conductor and, because your body is mostly water, electricity can easily travel through you to get to the ground. You could be seriously hurt or even killed. Remember, even if you are climbing a tree or a fence, you are still connected to the ground through the things your are standing on and can still be electrocuted.
Insulators
Insulators don't carry electric current very well. Some types of rubber, glass and plastic are really good insulators.
Electricity wires are covered in plastic so you cannot touch the metal core which carries the electricity - but the overhead power lines carried by pylons and in substations are not insulated at all - so keep well away from them. Pylons have ceramic or glass insulators to support the overhead lines so the pylon itself does not allow electricity to pass through it.
Even though some types of rubber are insulators, wearing rubber gloves or rubber-soled shoes or boots may not protect you from electric shock.
Build your own electrical circuits!
How much do you know about electrical circuits? Test your knowledge from the syllabus and try out our circuit builder game.
More lessons in this series
Quick tips about electrical safety
Dangerous situations
To stay safe, make sure you switch off the electricity before you plug in or unplug anything.
Never plug too many electrical appliances into one socket. The wires may overheat and catch fire.
Never poke things into electric sockets - you could easily be electrocuted.
Cables buried under road or footpaths could be carrying electricity and could kill you.
Never go fishing near overhead lines. Electricity might be carried down the fishing line back to you. You could be electrocuted.
Never poke things into electric toasters. The wires inside are uninsulated - you could easily be electrocuted.
Electric cables are often hidden behind walls. Make sure you know what is behind it using a cable detector from a DIY shop.
Never fly a kite near an overhead line. Electricity might be carried down the string back to you.
Building sites often have a live electricity supply. Do not go near them or you could get hurt or be killed.
Do not climb pylons or wooden poles, electricity can jump gaps if you get too close. Also, graffiti can cover warning signs and put others at risk.
Always keep electrical appliances away from water. Water conducts electricity - you could easily be electrocuted
Never climb into electricity substations or poke sticks through the fence. The high voltage electricity could kill you.
Before you climb any trees, always check there are no overhead lines nearby. If you get too close to an overhead line, you could be electrocuted.
Take extra care when mowing the grass with an electric lawn mower. If you damage the wire, you could be electrocuted.
Never play in derelict buildings - the electricity supply may not have been disconnected. You could be electrocuted.
Never touch exposed wires inside streetlights. You could be electrocuted.
Never play on or around railway lines, they carry high voltage electricity and you could be seriously hurt or killed.
Untidy wires might be tripped over or get damaged. Always make sure they are kept tidied away.
Never take electric appliances into the bathroom. Water conducts electricity - you could easily be electrocuted.
Did you know?
In 15 minutes, the sun radiates as much energy onto Earth as all the people on the planet during an entire year. Just imagine if we could channel the sun's energy effectively!
In August 1887 the London Electric Supply Corporation commissioned Ferranti to build the first power station. Today our electricity supply is still based on the system that Ferranti designed.
What is a volt? And why is it called a volt? The volt measures electromotive force. It was named after the Italian inventor Alessandro Volta (1745-1827)
In the 1780s, Alessandro Volta invented the first battery - all because of Luigi Galvani's experiments with dead frogs.
Thomas Alva Edison 1847-1931 is one of the most successful inventors ever, applying for over 1,300 patents by 1910, mainly to do with electrical or mechanical development.
High voltage electricity is carried across the country by pylons and 'stepped down' for domestic use at substations. The National Grid supplies electricity all over the country.