Nature of Electricity

The first recorded observation on electricity was made by the ancient Greek philosopher Phales. He stated that a piece of amber rubbed with fur attracted light objects. But more than 22 centuries passed before the study of magnetism and of electrical phenomena began by Galileo and other scientists.

It was well known that not only amber, but many other substances having been rubbed behave like amber i.e. can be electrified. It was discovered that any 2 dissimilar substances forced into contact and then separated became electrified, or acquired electrical charges.

During the 19^th century the idea of the nature of electricity was completely revolutionized. The atom was regarded as the ultimate subdivision of matter. Today the atom is regarded as an electrical system. In this electrical system there is a nucleus containing positively charged particles called protons. The nucleus is surrounded by lighter negatively charged units – electrons. So the most essential constituent of matter is made up of electrically charged particles. Matter is neutral and produces no electrical effects when it has equal amounts of both charges.

But when the number of negative charge is unlike the number of positive ones, matter will produce electrical effects. Having lost some of its electrons, the atom has a positive charge: having an excess of electrons – it has a negative charge.

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