# Definition: Ampere

From Open Energy Information

# Ampere

A unit of measure for electric current that refers to the amount of electric charge passing a point per unit of time; frequently abbreviated to “amp".^{[1]}^{[2]}

### Wikipedia Definition

- The ampere (SI unit symbol: A), often shortened to "amp", is the SI unit of electric current (dimension symbol: I) and is one of the seven SI base units. It is named after André-Marie Ampère (1775–1836), French mathematician and physicist, considered the father of electrodynamics.The ampere is equivalent to one coulomb (roughly 7018624100000000000♠6.241×1018 times the elementary charge) per second. Amperes are used to express flow rate of electric charge. For any point experiencing a current, if the number of charged particles passing through it — or the charge on the particles passing through it — is increased, the amperes of current at that point will proportionately increase.The ampere should not be confused with the coulomb (also called "ampere-second") or the ampere-hour (A⋅h). The ampere is a unit of current, the amount of charge transiting per unit time, and the coulomb is a unit of charge. When SI units are used, constant, instantaneous and average current are expressed in amperes (as in "the charging current is 1.2 A") and the charge accumulated, or passed through a circuit over a period of time is expressed in coulombs (as in "the battery charge is 7004300000000000000♠30000 C"). The relation of the ampere (C/s) to the coulomb is the same as that of the watt (J/s) to the joule., The ampere (SI unit symbol: A), often shortened to "amp", is the SI unit of electric current (dimension symbol: I) and is one of the seven SI base units. It is named after André-Marie Ampère (1775–1836), French mathematician and physicist, considered the father of electrodynamics.The ampere is equivalent to one coulomb (roughly 7018624100000000000♠6.241×1018 times the elementary charge) per second. Amperes are used to express flow rate of electric charge. For any point experiencing a current, if the number of charged particles passing through it — or the charge on the particles passing through it — is increased, the amperes of current at that point will proportionately increase.The ampere should not be confused with the coulomb (also called "ampere-second") or the ampere hour (A⋅h). The ampere is a unit of current, the amount of charge transiting per unit time, and the coulomb is a unit of charge. When SI units are used, constant, instantaneous and average current are expressed in amperes (as in "the charging current is 1.2 A") and the charge accumulated, or passed through a circuit over a period of time is expressed in coulombs (as in "the battery charge is 7004300000000000000♠30000 C"). The relation of the ampere (C/s) to the coulomb is the same as that of the watt (J/s) to the joule., The ampere (; symbol: A), often shortened to "amp", is the base unit of electric current in the International System of Units (SI). It is named after André-Marie Ampère (1775–1836), French mathematician and physicist, considered the father of electrodynamics.The International System of Units defines the ampere in terms of other base units by measuring the electromagnetic force between electrical conductors carrying electric current. The earlier CGS measurement system had two different definitions of current, one essentially the same as the SI's and the other using electric charge as the base unit, with the unit of charge defined by measuring the force between two charged metal plates. The ampere was then defined as one coulomb of charge per second. In SI, the unit of charge, the coulomb, is defined as the charge carried by one ampere during one second.

- Also Known As
- Amp

- Related Terms
- Electric current

##### References

- ↑ http://needtoknow.nas.edu/energy/glossary/
- ↑ http://www1.eere.energy.gov/site_administration/glossary.html#A