18WuD2x

electric generator • electric residue 235
+ −
Flux
lines
electric flux lines
Flux
lines
teries, dynamos, oscillators, solar cells, and thermocouples,
are classed as generators.
electric glow The light (usually pale blue) that occasionally
accompanies an electric discharge in
air.
electric guitar A guitar whose acoustic vibrations
are converted by a transducer to an electrical signal
for amplification.
electric hygrometer An instrument for measuring
humidity in terms of the moisture-sensitive resistance
of a sensor. A relatively simple directcurrent
(dc) circuit is used. Compare
ELECTRONIC HYGROMETER.
electric hysteresis See ELECTROSTATIC HYS-
TERESIS.
electrician A professional person who installs and
services electrical equipment and wiring.
electric image For solving certain problems involving
electricity, an array of electrical points
forming an image of certain other electrical
points.
electricity 1. Phenomena resulting from the existence
of stationary or moving electric charge carriers,
such as electrons, holes, and ions. 2. A
branch of physics concerned with phenomena resulting
from the existence of stationary or moving
charge carriers. 3. Electrical energy or power. 4.
The voltage existing at utility outlets. In the North
America, this is nominally an alternating-current
(ac) voltage of 117 or 234 V at 60 Hz.
electric lamp An electric-powered device used primarily
as a source of light. Common types are
arc, incandescent, and fluorescent.
electric light 1. Visible light produced by means of
electricity. 2. Electric lamp.
electric lines of flux Lines of flux associated with
an electric charge and constituting the charge’s
electric field.
electric machine A mechanical device for generating
static electricity. See, for example, ELEC-
TROSTATIC GENERATOR, VAN DE GRAAFF GEN-
ERATOR, and WIMSHURST MACHINE.
electric meter 1. An instrument such as an ammeter,
voltmeter, or wattmeter, used to indicate
an electrical quantity (usually directly). 2. See
KILOWATT-HOUR METER.
electric mirror See ELECTRON MIRROR.
electric moment In an electric field of unit intensity,
the maximum torque exerted on an electric
dipole.
electric motor A machine that converts electrical
energy into mechanical work. The familiar form is
a machine in which an armature rotates between
the poles of a field magnet, mechanical energy being
produced at the armature’s revolving shaft.
electric needle A needle electrode carrying highfrequency
current; it is used in surgery to cut tissue
and sear it immediately to prevent bleeding.
electric network See ELECTRICAL NETWORK.
electric organ See ELECTRONIC ORGAN.
electric oscillations The alternate flow of electric
charges in opposite directions, occurring at a defined
frequency or frequencies.
electric osmosis See ELECTRO-OSMOSIS.
electric piano See ELECTRONIC PIANO.
electric polarization 1. The orientation of flux
lines in an electric field. 2. The orientation of the
electric field component in an electromagnetic
field.
electric potential See ELECTROSTATIC POTEN-
TIAL.
electric power Symbol, P. Unit, watt. The rate at
which electrical energy is used. Power is energy
per unit time; in the context of electricity, it is expressed
as the product of current and voltage. In
terms of heat losses, it is often expressed as I 2 R
(current in amperes squared, multiplied by resistance
in ohms).
electric precipitator See DUST PRECIPITATOR.
electric probe A pin or rod inserted into an electrostatic
field to sample it, or into an electromagnetic
field to sample its electric component. See,
for example, WAVEGUIDE PROBE. Compare
MAGNETIC PROBE.
electric radiation 1. The radiation of energy by
means of electric waves. 2. The energy so radiated.
electric recording Inkless recording on paper by
direct use of an electric current. The two principal
types are: (1) A current-carrying stylus burns
away (in a fine line) the metallic coating of the
recording paper, exposing the dark underlying
layer. (2) A stylus delivers current that produces
a line by means of electrolysis in a special paper
(see ELECTROLYTIC RECORDER). Compare
ELECTROSTATIC PRINTER.
electric reset See ELECTRICAL RESET.
electric residue A residual electric charge, such as
might remain on a capacitor after it has been incompletely
discharged.