The ampere (symbol: A) is the SI unit of electric current. The ampere, in practice often shortened to amp, is an SI base unit, and is named after André-Marie Ampère, one of the main discoverers of electromagnetism.
In practical terms, the ampere is a measure of the amount of electric charge passing a point per unit time. Around 6.242 × 10 electrons passing a given point each second constitutes one ampere. (Since electrons have negative charge, th...
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The ampere (symbol: A) is the SI unit of electric current. The ampere, in practice often shortened to amp, is an SI base unit, and is named after André-Marie Ampère, one of the main discoverers of electromagnetism.
In practical terms, the ampere is a measure of the amount of electric charge passing a point per unit time. Around 6.242 × 10 electrons passing a given point each second constitutes one ampere. (Since electrons have negative charge, they flow in the opposite direction to the conventional current.)
Qualitatively, the ampere "is now defined in terms of a current that, if maintained in two straight parallel conductors of specific sizes and positions, would produce a certain amount of [magnetic] force between the conductors." Quantitatively, the ampere is defined to be the constant current which will produce an attractive force of 2 × 10 newtons per metre of length between two straight, parallel conductors of infinite length and negligible circular cross section placed one...
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