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Electricity and magnetism

What is electricity and how is it made?

Inside an atom, electrons orbit the nucleus.Inside an atom, electrons orbit the nucleus.Electricity is a kind of energy stored inside atoms, the minute building blocks of which all things are made. Atoms themselves are made up of particles, including electrons, which have a negative electric charge, and protons, which have a positive electric charge. In normal atoms, there are the same number of electrons and protons, and so the charges cancel each other out. But when an atom loses or gains an electron, it becomes electrically charged, either positively (if it loses one) or negatively (if it gains one). The atom is then known as an ion. To make electricity, we must either make the atoms lose or gain electrons, or enable free electrons to move. 


Sparks of electricity leap through the airSparks of electricity leap through the airProducing static electricity by combingProducing static electricity by combing

Static electricity

Static electricity is produced when two objects rub against each other: the electrons rub off from the atoms of one material on to the other. You can make static electricity by running a comb through your hair. The comb leaves a few of its electrons behind in the hair, so the comb now has a small positive charge. It can pick up small pieces of paper because it attracts the electrons in the paper’s atoms. If you comb your hair in a dark room then hold the comb close to your thumb, you will see a tiny spark. The release of electricity heats the air molecules (groups of atoms) between comb and thumb, producing a flash of light.

The word electricity comes from the Greek electron, meaning amber (fossilized tree resin). This is because static electricity could be produced by rubbing amber.

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