TWO FUNDAMENTAL LAWS OF ELECTRICITY

№1. TWO FUNDAMENTAL LAWS OF ELECTRICITY

An electric current is the movement or flow of electrons. To understand what an electron is, we must first think of matter and how it is constructed, or made up. The smallest piece of any substance is called an atom. An atom is made up of a smallest particle called a proton, which has a positive electric charge, and a number of electrons which have a negative charge. When two charges are equal, the atom is neutral. Until an atom is charged, it will remain in its original form. It is held together because opposite or unlike charges are attracted to each other. Like or similar charges of electricity repel or oppose each other. These are two fundamental laws of electricity.

№ 2. HOW IS ELECTRICITY FORMED?

Electricity is made in many ways. One way is by a battery, as used in a transistor radio. A simple battery has a positive terminal or pole connected to a carbon rod. The carbon rod is placed in a chemical paste inside zinc container. The negative terminal is attached to the zinc container. The action of the chemicals causes the poles to become charged. Any material which will allow electricity to flow through it is called a conductor. If the terminals of a battery are connected by a metal wire, the free electrons will flow along it towards the opposite terminal. This is an electric current. A simple battery converts or changes chemical energy into electrical energy.

№ 3. SOME WAYS OF PRODUCING ELECTRICITY

A simple battery converts, or changes, chemical energy into electrical energy. Other forms of energy, such as heat and light, may be converted into electricity. The most common way of making electricity is by the conversion of mechanical energy. A dynamo is a machine which makes electricity when it is made to rotate, or turn, at high speed. It is often driven by a turbine, which may be made to rotate by steam pressure. This machinery is called turbogenerator. A building which houses a turbo-generator is called a power or generating station. A station which uses the power of falling water is known as a hydropower or hydroelectric station. Most of the world's electricity for domestic and industrial use is made or generated in such power stations.

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