Electricity And Magnetism – A Close Relationship
Electricity for most of us simply means electric power provided by the electric companies to households and industries so that devices, appliances and equipment that require such power can run. This is however not a precise definition of electricity. Electricity is a general term that covers a lot of different phenomena that comes about because of the presence and movement of an electrical charge. Examples of these phenomena are lightning, static electricity, the electrical current that runs in homes, offices and industries and the electromagnetic field. Electricity and magnetism are two topics that are often tackled in relation to each other. This is because the two are closely related and very similar.
Basic properties of electricity and magnetism will illustrate why these two phenomena are closely related. Electricity as earlier mentioned is the presence and motion of an electric charge, magnetism in general terms on the other hand is the property of an object that enables it to attract another object. Electricity involves electrically charged positive and negative particles. Particles with the same charge repel while particles with opposite charges attract. Magnets on the other hand have what are called north poles and south poles. Two magnets only attract when the north pole of one of the magnets is placed beside the south pole of the other magnet. In other words, like poles repel and opposite poles attract. Another similarity of electricity and magnetism is that in electricity, current flows from negative to positive poles. In much the same way, in magnets the magnetic field or field lines travel from North to South.
It was a Danish chemist and physicist named Hans Christian Orstead who accidentally discovered a connection between electricity and magnetism more than 100 years ago. Orstead while demonstrating something to his class accidentally placed a compass over an electric wire. When he did, the compass’ needle suddenly moved to a position perpendicular to the current making him conclude that electricity and magnetism are two related phenomena.