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electret microphone • electrical engineer 231
audio-frequency (AF) output current. An internal
power supply (such as a battery) supplies
the necessary voltage.
electric 1. Pertaining to electricity and its various
manifestations. 2. See ELECTROSTATIC.
electric absorption See DIELECTRIC ABSORP-
TION.
electric accounting machine A self-contained
data-processing machine that is neither a computer
nor a computer peripheral.
electrical-acoustical transducer A transducer,
such as a headphone, sonic applicator, or buzzer,
that converts electrical energy into sound energy.
Compare ACOUSTICAL-ELECTRICAL TRANS-
DUCER.
electrical angle The angle assumed at any instant
by the rotating vector representing an alternating
current or voltage. A complete cycle is divided
into 360 electrical degrees. Thus, for an alternating-current
(ac) sine wave, the angle is 0 degrees
for zero and positive-going, 90 degrees for positive
maximum, 180 degrees for zero and negativegoing,
and 270 degrees for negative maximum.
−
Amplitude
y
+
−
electrical angle
θ +
Rate of
x
change
electrical attraction The attraction between two
oppositely charged bodies or particles. Compare
ELECTRICAL REPULSION.
electrical axis In a quartz crystal, the axis through
opposite corners of the hexagonal cross section.
The various electrical axes are x, x’, and x” (or x-
x, x’-x’, and x”-x”). The electrical axis is perpendicular
to the mechanical axis, which runs
through the crystal’s length. Also see CRYSTAL
AXES and X-AXIS, 2.
electrical bail An action in which a special switch
changes contact position and locks itself in that
position after a station has been actuated, at the
same time releasing a previously actuated station.
electrical bandspread In a tuned circuit, bandspread
obtained by changing values of inductance
or capacitance, rather than by mechanical
gearing.
electrical bias A current maintained in a relay coil
(sometimes an auxiliary coil) to keep the relay
partially closed, thus sensitizing it. Compare ME-
CHANICAL BIAS.
electrical boresight In radar operations, the
tracking axis, as determined by an electrical test,
such as one involving a sharp null or sharp peak
response.
electrical center The point at which an adjustable
component (variable resistor, variable inductor,
etc.) has exactly half its total value. This point
does not always coincide with the physical center.
electrical conductance See CONDUCTANCE.
electrical conduction The flow of charge carriers
through a material. The degree of conduction is
indicated by the material’s value of conductance.
electrical conductivity See CONDUCTIVITY.
electrical coupling The coupling of two or more
circuits or elements by means of electric-field effects.
electrical degree 1. In a periodic waveform, the
length of time corresponding to 1 ⁄360 of the time for
completion of one cycle. 2. In space, that distance
representing 1 ⁄360 of the wavelength in the
medium through which electromagnetic energy
travels.
electrical discharge The flow of current out of a
voltage reservoir, such as a battery or capacitor.
electrical discharge in gases The phenomenon of
electric conduction (current) by a gas, caused by
sudden breakdown as a result of gas ionization.
The discharge is often accompanied by light, as in
the red glow of a neon bulb.
electrical-discharge machining A method of machining
metals in which the metal is vaporized by
an arc formed between an electrode and the metal
workpiece (anode). In this way, metal is removed
in tiny bits from the surface of the workpiece.
electrical distance Distance in terms of the time
required for an electromagnetic wave to travel between
two points in a particular medium.
electrical drainage The diversion of electric currents
away from underground pipes to prevent
corrosion by electrolysis.
electrical efficiency The ratio of the output of an
electrical or electronic device to the total input. It
can be expressed as a decimal or percentage. For
example, for a bipolar transistor amplifier, the
percent efficiency is equal to 100(P out /P in ), where
P in is the collector input in volt-amperes, and P out
is the output power in watts.
electrical elasticity See CAPACITANCE.
electrical element See ELEMENT, 2.
electrical energy Energy in the form of electricity
(see ELECTRICITY, 1). The term is often used in
place of ELECTRICITY.
electrical engineer Abbreviation, EE. A trained
professional skilled in applying physics and mathematics
to electricity, and in the theory and application
of basic engineering and related subjects.
Of particular interest to the EE are the generation