ELECTRICITY

One of the most useful forms of energy in today’s world is electricity. It is transportable, which means it can be carried long distances by wires and cables. It is convertible, being changed into many other forms of energy, such as light from an electric light-bulb, and movement in an electric motor. It is also controllable. We can turn it on and off with a switch, or up and down with a knob. When a city suffers a power cut and falls still and silent, we realize how much we depend on electricity.

Electricity is the movement of electrons, the negative particles around the nucleus of an atom. Most metals, especially silver and copper, have electrons that can move easily from atom to atom, so they are good carriers or conductors of electricity. Electrons are pushed along the conductor by a battery or generator. But they flow only if they have a complete pathway of conductors called a circuit. Flowing electricity is known as electric current.

In substances such as rocks, wood, plastics, rubber and glass the electrons do not move easily. These materials prevent the flow of electricity and are known as insulators, but they may gain or lose electrons on their surface as a static electric charge.

            Static electricity is produced when electrons are separated from their atoms. On a comb it attracts bits of paper. In the sky it causes lightning!

            Electric current flows along a wire as electrons which detach from the outermost parts of their own atoms and jump or hop along to the next available atoms.

Picture Credit : Google