Page 248 - Electrical Engineering Dictionary

electric field intensity a force field that is electric vehicle a vehicle powered by an
a measure of the magnitude and direction of electrical energy storage device such as bat-
theforceimparteduponadiscretechargenor- teries.
malized to the discrete charge’s value. De-
pends on material characteristics. The units electrical breakdown See breakdown.
are volts per meter.
electrical degrees a convenient way of
representing the distance around the circum-
electric flux density basic electromag-
ference of a machine with two poles spanning
netic field quantity used to describe the ef-
the entire 360 of the circumference,
◦
fects of permeable matter to the electric field;
it is expressed in SI units of coulombs per
Electrical Degree = Pairs of poles
square meter.
× Mechanical Degree
electric furnace a method of smelting
metals and applying high heat for industrial
electrical network a collection of inter-
processes which makes use of the heat from
connected electrical devices.
an electric arc struck between (typically) car-
bon electrodes.
electrical tree a microscopic cracking
pattern which forms in the insulation of elec-
electric permittivity tensor relationship tric power cables which are not exposed to
between the electric field vector and the elec- water See tree, water tree.
tric displacement vector in a medium with no
hysteresis; displacement divided by the elec- electrically alterable read-only memory
tric field in scalar media. (EAROM) a PROM device that can be
erased electronically. More costly than the
electric polarization vector an auxil- EPROM (erasable PROM) device, which
iary vector in electromagnetics that accounts must be erased using ultra-violet light.
for the creation of atomic dipoles in a di-
electrically erasable programmable read-
electric material due to an applied electric
only memory (EEPROM) a nonvolatile
field. Macroscopically, the electric polariza-
semiconductor memory, it is used at the
tion vector is equal to the average number
place of PROM or EPROM. They can be
of electric dipole moments per unit volume.
programed and erased by electrical means.
Mathematically, P = D − 0 E, where D is
the electric flux density, E is the electric field
intensity, and 0 is the free space permittivity.
SI units are coulombs per square meter.
electro-acoustic smart material one of
severalmaterialsthathaveself-adaptivechar-
electric susceptibility tensor relationship
acteristics in their acoustic behavior (such
between the electric field vector and the elec-
as transmission, reflection, and absorption of
tric polarization vector in a medium with no
acoustical energy) in response to an external
hysteresis. It is the polarization divided by
stimulus applied as a function of the sensed
the permittivity of free space and the electric
acoustical response.
field in scalar media.
electro-optic coefficient a parameter that
electric vector potential avectorfunction describes the change in refractive index in a
that is used to derive solutions for electric and medium with application of an electric field.
magnetic fields. The linear electro-optic coefficient describes

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