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fact sheet: Unusual Water

Static Electricity

Have you ever gotten a small electric shock when you've touched something metal? Have you tried rubbing a balloon against your hair and seen how your hair stands on end and how the balloon can stick to a wall? If you haven't, get a balloon and try it for yourself!

These are all examples of static electricity. We say that the balloon has become charged. It has static electricity.

Getting Charged

If an object is uncharged, it has equal amounts of positive and negative charges. The positive charges are called protons and the negative charges are called electrons. If these charges are balanced, the object is neutral.

If there are different numbers of positive and negative charges, the charges are unbalanced and the object is charged. If there are more negative electrons, the object has a negative charge. If there are more positive protons the object has a positive charge.

An object can be charged by knocking off its negative electrons.

If you take a strip of plastic polythene and rub it with a dry dusting cloth, you can knock some electrons off the cloth and onto the polythene. This makes the cloth have a positive charge. The polythene has gained some more electrons, so it now has a negative charge.

Shocking!!

Sometimes when you walk towards your car door, you knock electrons off the pavement (or whatever you've just walked over) and onto you. You now have a negative charge. When you touch the metal handle of a car, the negative electrons flow out of you and onto the car.

Whenever electrons move, or flow, this is called electricity. You get a little electric shock as the electrons move from you and onto the car.

Click here to investigate static electricity and water.

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