electro-, electr-, electri-

1. Any electrical device; such as, a switch or a potentiometer (a resistor with three terminals, the third being an adjustable center terminal; used to adjust voltages in radios and TV sets), which is used to vary a circuit parameter.
2. The control of a machine by electric switches, relays, rheostats, or a resistor designed to allow variation in resistance without breaking the electrical circuit of which it is a part.
3. The control of a machine or instrument by switches, relays, or rheostats, as contrasted with electronic control by electron tubes or by devices which do the work of electron tubes.

1. An apparatus that regulates or governs in some predetermined manner the amount of electric power which is delivered to an apparatus.
2. An instrument which regulates the electric power that is delivered to a piece of machinery, a tool, or a device which is used for a specific purpose.

1. A converter in which motor and generator windings are combined on one armature and excited by one magnetic field: A synchronous converter is normally used to change alternating to direct current and is also known as a converter or electric converter.
2. A synchronous device used to convert alternating current (AC) to direct current (DC), or the reverse: The AC-to-DC converter, provided by the synchronous converter, has been replaced by a mercury arc rectifier (for reasons of efficiency, lower maintenance costs, and fewer problems) or by motor-generator sets.

A discharge of electricity appearing as a bluish-purple glow on the surface of and next to a conductor when the voltage gradient exceeds a certain critical value resulting from the ionization of the air in the area around the high voltage.

1. A magnetic-field coupling between the shafts (cylindrical pieces of metal used to carry rotating machine parts) of a driver and the vehicle being driven.
2. A rotating machine whose torque is transmitted or controlled by electric or magnetic processes.

The current per unit of a cross-sectional area of a conductor.

1. An instrument that is used for measuring the magnitude of electric current flow.
2. A device which is used to measure the magnitude of an electric current of several amperes or more.

An ammeter is usually combined with a voltmeter and an ohmmeter in a multipurpose tool.

1. The time rate of flow of an electric charge, in the direction that a positive moving charge would take and having magnitude equal to the quantity of charge per unit of time measured in amperes.
2. Charged particles, most often electrons, moving through a conductor or transmitter; such as, copper and aluminum.
3. A flow of charged particles; such as, electrons or protons, accompanied by the field which they generate.
4. Movement of electric charge carriers.

In a wire, electric current is a flow of electrons that have been dislodged from atoms and is a measure of the quantity of electrical charge passing any point of the wire per unit of time.

1. Pairs (two conductors employed to form an electric circuit) that are brought out of a cable and terminated at some place other than at the end of the cable.
2. An electrical instrument which is used to interrupt the flow of current through any special apparatus or instrument, either automatically or manually.

1. An instrument which postpones an electric signal's arrival time in a circuit by employing capacitive (a system that enables it to store an electric charge) and inductive properties (production of an electromotive forces).
2. A delay line that uses properties of lumped or distributed capacitive and inductive elements.

It can be used for signal storage by recirculating information-carrying wave patterns.

1. A method for removing impurities from crude oil by settling out in an electrostatic field.
2. A process used to remove impurities; such as, inorganic salts from crude oil by settling them out (gravity separation of heavy from light materials) in an electrostatic field.

1. An explosive device activated by a fuse wire that initiates the operation of a primer.
2. A detonator ignited by a fuse wire which serves to touch off the primer.

1. A localized distribution of positive and negative electricity, without a net charge, whose mean positions of positive and negative charges do not coincide.
2. A pair of equal and opposite electric charges, the centers of which do not coincide.
3. Any object or system which is oppositely charged at two points, or poles; such as, a magnet or a polar molecule.
4. A pair of equal and opposite charges an infinitesimal distance apart from each other.

A quantity that is characteristic of a charge distribution, equal to the vector sum over the electric charges of the product of the charge and the position vector of the charge.

The primary process by which an atom produces or absorbs radiation when it changes from one energy level to another one: An electric dipole transition takes place when an oscillating electric field interacts with the electric dipole (a separation of positive and negative charges) movement of an electron inside an atom during which an electric radiation is discharged or absorbed.