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Energy & Forces - Conversion & transfer of energy - Electricity - G13
This is the Teacher's Guide for this targetThis is the Teacher's Guide for this targetTeacher's Guide


 1. Working with static electricity is not always predictable. Demonstrations of the effects of static tend to work better in dry conditions and so try to choose a dry day and work in the morning before the vapour level in the class builds up.

2. To show the children the effects of static do some simple demonstrations. Firstly take a plastic comb or ruler (these are better options than an acetate or polythene rod) and rub it vigorously about 10 times with a clean, dry cloth ( a yellow duster is ideal). You will now be able to pick up small pieces of tissue paper with the comb.

Rub a ruler or comb again with the dry cloth and this time turn on a cold tap so that there is a steady gentle stream running. Hold the charged ruler close to the stream and you should see the stream of water bend as it passes the ruler. (Practice this before trying to show the class.)

A nice variation of this is to make the ruler a fishing rod and to cut out several ‘fish’ shapes from some coloured tissue. How many fish can your charged ruler catch?

Static Electricity

We are all used to electricity from the mains and from batteries. This type of electricity flows and is called ‘current’ electricity. There is another type called ‘static’ electricity which stays in one place. Static electricity happens when two things are rubbed together so that one thing rubs off tiny parts of the atoms of the other thing. These tiny parts are called electrons. The item with the extra electrons will now be pulled to anything which is short of electrons but will be pushed away from anything which has too many electrons. so when you rub a balloon against a jumper, the balloon picks up some extra electrons from the wool. It will now stick to anything which has a need of electrons but will push away from another rubbed balloon which also has too many electrons.

We call the item which has picked up electrons ‘negatively charged’ and the thing which has lost electrons is called ‘’positively charged’.

3. The children will all be familiar with thunder and lightning and this is a good opportunity to talk about thunderstorms, how lightning can hit the ground and how to count the time between a lightning flash and the sound to see how many miles away the storm is. Some safety aspects should be mentioned - never shelter under a tree in a thunderstorm - try to get into a building or stay in a car and so long as you are completely within the car, you should remain unharmed in the event of a direct hit.

If you cannot find any shelter, and feel your hair ‘standing on end’ a strike is imminent - get close to the ground so that you are not the tallest thing around.

In the classroom we cannot make lightning but can make a tiny spark.

Making a Spark

An enjoyable demonstration which the children can repeat themselves, is easily done using a small cake tin, a metal teaspoon, a lump of plasticine and a black bin bag. Sellotape the bag out flat on the table and make the plasticine into a handle on the inside of the tin. Hold the tin using the plasticine handle and rub it around in a circle about ten times on the bin bag. Lift it off the bag and hold the teaspoon very close to the tin and a tiny spark should jump across from the tin to the teaspoon. Again this will work better some days than others but it makes a tiny crackle as it jumps and the children will have to be very quiet to try and hear it! It might be seen better in a darkened room and may work better with an acetate sheet rather than a bin bag.

Another way of showing charges. First charge the tin as described above. Now hold the tin close to the nose, but not touching it, the charged tin makes the nose tickle!


Thunder and lightning are caused by static electricity. Clouds become charged as the tiny ice crystals inside them rub against each other. A cloud can get so charged up that electrons jump between it and the ground, or another cloud. This causes a huge spark which is lightning. Sometimes the spark will jump to another cloud and sometimes it will jump to Earth. The noise of lightning which we call ‘thunder’ is caused by the spark ripping through the air. Because light travels very much faster than sound we see the lightning before we hear the thunder. The time between the two depends on how far away we are from the spark.

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