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Alligator Clip

A long-nosed, spring-loaded metal clip with meshing teeth. Used to make temporary electrical connections

Allotropic

A term that applies to elements that appear in more than one form, though their atomic composition is the same. For example, the properties of graphite and diamond are the same as the element carbon (C). Since their physical properties are entirely different, both are called an allotropic of carbon.

Alloy

A metal containing additions of other metallic or nonmetallic elements to enhance specific properties such as strength and corrosion resistance.

Alloy Powder

Powder prepared from a homogeneous molten alloy or from the solidification product of such an alloy.

Alloy Steel

Steel containing specified quantities of alloying elements added to effect changes in mechanical or physical properties.

Alloys

Light-weight aluminum or magnesium alloy wheels. Also see mags.

Alnico

A permanent-magnet alloy of aluminum, nickel, and cobalt.

Alpha Particle

A particle that is a by-product of radioactive decay. It has a positive electrical charge that is twice the negative charge of an electron.

Alpha Version

A very early version of a software product.

Alphanumeric

Describes the combined set of all letters in the alphabet and the numbers 0 through 9 Sometimes additional characters are considered alphanumeric, for example, on IBM mainframe computers the charaters @, #, and $ are used.

Alt

An abbreviation for alternator. Also, may be used as an abbreviation for alternate or altitude.

Altered

A drag-racing vehicle with a stock-looking coupe, roadster, or sedan body, but without normal street equipment. The engine and/or cockpit may be moved to the rear for better weight distribution.

Alternate Mode

A Display mode of operation in which the oscilliscope completes tracing one channel before beginning to trace another channel.

Alternating Current (ac Or Ac)

[1] The type of electrical current actually produced in an alternator. [2] A current flow that begins at "0" volts with the passage of a magnet and flows in one direction as it's inducted voltage increases to its maximum then decreases to its minimum then the inducted voltage induced by the opposite end of the magnet increases from "0" again however the current flows in the opposite direction.

Alternative Refrigerant

A refrigerant that can be used to replace an existing refrigerant, such as ozone friendly HFC-134a that is used to replace ozone depleting CFC-12.

Alternator

An electricity-generating device that converts mechanical energy to electrical energy in the form of alternating current. Diodes rectify the alternating current into direct current.

Altitude

The distance of a point above sea level. Important to automotive emissions control because the higher the altitude, the fewer oxygen molecules per given volume of air, which alters the effective compression and air/fuel ratios.

Altitude Compensation System

An altitude barometric switch and solenoid used to provide better driveability at more than 4,000 feet (1,219 meters) above sea level.

Alu

Arithmetic Logic Unit, which is the part of the computer containing the necessary designed circuitry to carry out the computational information requirements such as addition, subtraction, multiplication, division, and comparing of poerations of a digital system.

Alum

1. A crystallized double sulfate of aluminum (Al) and potassium (K). 2. More commonly, an acronym for aluminum (Al).