Ampeeriä

Ampeeriä is the Finnish partitive form of ampeeri, the SI unit of electric current. The ampere, symbol A, measures the rate of flow of electric charge in a circuit. In modern definitions, one ampere is the current that, if carried by two parallel conductors of infinite length and negligible resistance, would produce a force between the conductors equal to 2×10^-7 newtons per meter of length. Since 2019, the ampere is defined by fixing the elementary charge e to exactly 1.602176634×10^-19 coulombs, making one ampere equal to one coulomb per second.

The unit is named after the French physicist André-Marie Ampère, a foundational figure in electromagnetism. In Finnish usage, ampeeriä occurs as a grammatical form indicating quantities of current, such as when referring to multiple amperes or to an undetermined amount of current in a measurement or calculation.

Applications and context follow the general role of the ampere in science and engineering. It is used to describe electrical circuits, power systems, and electronic devices, with typical household currents ranging from a few amperes to tens of amperes depending on the apparatus. Measurement accuracy depends on appropriate instruments, such as ammeters, and on circuit conditions, including resistance and impedance.

Related concepts include the coulomb (unit of electric charge), the volt (potential difference), and fundamental constants that underpin the precise definition of the ampere. The term ampeeriä, while primarily a Finnish grammatical form, is encountered in technical Finnish text whenever current quantities are discussed.