Current, Alternating

A natural current produced by the action of electro-magnets. It is a succession of short impulses in opposite directions.

Current, Constant

A current which is uniformly maintained in a steady stream.

Current, Induced

A current produced by electro-dynamic induction.

Current Meter

An apparatus for indicating the strength of a current. An ammeter.

Current, Oscillating

A current which periodically alternates.

Current, Periodic

A periodically varying current strength.

Current, Undulating

A current which has a constant direction, but has a continuously varying strength.


The separation of a liquid, such as an electrolyte, into its prime elements, either electrically or otherwise.


The change of movement of a magnetic needle out of its regular direction of movement.


When a current passes through a coil wound on an iron core, the core becomes magnetized. When the current ceases the core is no longer a magnet. It is then said to be demagnetized. It also has reference to the process for making a watch non-magnetic so that it will not be affected when in a magnetic field.


The quantity of an electric charge in a conductor or substance.


The removal of magnetism from a permanent magnet, or a horse-shoe magnet, for instance. It is generally accomplished by applying heat.

Deposition, Electrolysis

The act of carrying metal from one pole of a cell to another pole, as in electroplating.


Mechanism for indicating the presence of a current in a circuit.


A plate in a telephone, which, in the receiver, is in the magnetic field of a magnet, and in a transmitter carries the light contact points.


A non-conductor for an electric current, but through which electro-static induction will take place. For example: glass and rubber are dielectrics.


The current flowing from an accumulator.


The breaking up of the plate or active material.


A static discharge passing through a dielectric.

Duplex Wire

A pair of wires usually twisted together and insulated from each other to form the conducting circuit of a system.

Dynamic Electricity

The term applied to a current flowing through a wire.


An apparatus, consisting of core and field magnets, which, when the core is turned, will develop a current of electricity.

Earth Returns

Instead of using two wires to carry a circuit, the earth is used for what is called the return circuit.


The total electrical energy produced, in which that wasted, as well as that used, is calculated.