Converter
electric current · International · Modern
ampere
Aexact
- Record
- M502
- Definition quality
- Standardized
- Conversion mode
- multiplicative
- Calculator
- Fully calculable
Definition
SI base unit of electric current. The elementary charge is fixed exactly at 1.602176634×10^-19 C, with C = A·s.
History & use
The 1948 definition was based on the force between ideal parallel conductors. The 2019 revision instead fixed the elementary charge.
Modern use
International SI base unit for electric current.
Did you know?
The old definition imagined infinitely long parallel wires; the modern definition is tied to the exact charge of the electron/proton magnitude.