Page 53 - The Illustrated Dictionary of Electronics

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38 arc cosecant • area code

radians or degrees, corresponding to a given
cosecant.
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arc cosine Abbreviated arc cos or cos . 1. The in- arc length The length along a given arc, usually a
verse of the cosine function. 2. The angle, in radi- part of the circumference of a circle. If the circle
ans or degrees, corresponding to a given cosine. has circumference C and the arc measures x de-
arc cotangent Abbreviated arc cot or cot . 1. The grees, then the arc length is Cx/360 units.
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inverse of the cotangent function. 2. The angle, in arc minute See MINUTE.
radians or degrees, corresponding to a given arc oscillation Oscillations that can occur when
cotangent. opening relay contacts arc.
arc failure 1. Damage to, and/or failure of, insula- arcover The occurrence of an electrical ARC be-
tion or a dielectric as a result of ARCOVER. 2. tween electrodes, contacts, or capacitive plates.
Failure of make-and-break contacts through arcover voltage The voltage at which disruptive
damage caused by arcover. discharge occurs, typically accompanied by an
arc function An inverse trigonometric function. See arc.
ARC COSECANT, ARC COSINE, ARC COTAN- arc resistance The ability of a material, usually a
GENT, ARC SECANT, ARC SINE, and ARC TAN- dielectric, to resist damage from arcing. This
GENT. property is commonly expressed as the length of
arc furnace A high-temperature electric furnace in time between the start of the arc and the estab-
which heat is produced by one or more electrical lishment of a conductive path through the mate-
arcs. rial.
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architecture The functional design elements of a arc secant Abbreviated arc sec or sec . 1. The in-
computer—especially the components of the cen- verse of the secant function. 2. The angle, in ra-
tral processing unit (CPU) and the manner in dians or degrees, that corresponds to a given
which these elements interact. secant.
archived file A computer file stored on some arc second See SECOND.
backup medium, such as magnetic tape, disk- arc sensor A device for detecting visible arcs and
ette, or CD-ROM (compact disk, read-only mem- excessive reflected power in microwave systems.
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ory), rather than being held on the hard disk. arc sine Abbreviated arc sin or sin . 1. The inverse
Such a file will be apart from the operating sys- of the sine function. 2. The angle, in radians or
tem’s catalog of current files, but can be reconsti- degrees, that corresponds to a given sine.
tuted as needed. arc suppression Extinguishing an arc discharge.
archives A complete, periodically updated set of Disruptive arcs in electronic circuits are sup-
ARCHIVED FILES. pressed by means of auxiliary diodes or resistor-
arcing See ARCOVER. capacitor networks.
arcing contacts Make-and-break contacts be- arc-suppressor diode A semiconductor diode used
tween which an arc occurs when they are sepa- to prevent arcing between make-and-break con-
rated. tacts.
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arcing ring A metal ring placed around an insula- arc tangent Abbreviated arc tan or tan . 1. The
tor in a high-voltage electrical system. This keeps inverse of the tangent function. 2. The angle, in
an arc from charring or breaking the insulator. radians or degrees, corresponding to a given tan-
arcing time The elapsed time between the break- gent.
ing of contacts and the end of the arc between the arcthrough The puncturing of a material by an
contacts. arc.
arc lamp An electric lamp in which a brilliant arc area code In the United States, a three-digit
jumps between the tips of two rods (originally car- number that indicates the location, according to
bon). specified assigned districts, of a telephone sub-