ampere (redirected from Amperes)

ampere (ăm`pēr), abbr. amp or A, basic unit of electric current. It is the fundamental electrical unit used with the mks system of units of the metric system. The ampere is officially defined as the current in a pair of equally long, parallel, straight wires 1 meter apart that produces a force of 0.0000002 newton (2 × 10⁻⁷ N) between the wires for each meter of their length. Current meters such as ammeters and galvanometers are calibrated in reference to a current balance that actually measures the force between two wires.

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A measurement of electrical current in a circuit, commonly called an "amp." Contrast with "volts," which is a measure of force, or pressure, behind the current. Multiplying amps times volts derives "watts," the total measurement of power. In electrical equations such as Ohm's Law, the symbol for ampere is "I" (see Ohm's Law).

One ampere is 6,280,000,000,000,000,000 (6.28 x 10¹⁸) electrons passing by the point of measurement in one second. See ampere-hour, volt and watt.

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(unit, electronics)

Ampere - (Amp, A) The unit of electrical current flow. One Amp is the current that will flow through a one-ohm resistance when one Volt DC is applied across it.