What does induction mean?

   Induction is a term used in physics to denote the action of an electrified body or a magnet in producing an electrified condition or magnetism in another body without coming in contact with it. It is called electrostatic induction when a charged body brought near an insulated one causes a separation of the positive and negative electricity in it, the opposite in kind being attracted. The repelled charge, similar in kind, may be removed, when the second body is left oppositely charged. This is called charging by induction. When a magnet is brought near an unmagnetized piece of soft iron, the latter becomes a magnet by induction. Removing the magnet, the soft iron loses its polarity. The term electromagnetic induction is applied to the power of a current to produce polarity in a piece of iron near it or around which it flows. Such a magnet is called an electromagnet. Then again an intermittent current will produce a flow of electricity in a closed conductor near it. It is the change in the inducing current. which causes the second. This has given rise to the instrument known as an induction coil whereby a weak current automatically made and broken in a coil of coarse wire, produces one of much greater intensity in a coil of fine wire surrounding it. Transformers used in the transmission of electrical energy are mere induction coils.