| Above: | abampere or biot |
| Label3: | Unit of |
| Label4: | Symbol |
| Data4: | abA or Bi |
| Label5: | Named after |
| Label6: | In CGS base units |
| Data6: | g⋅cm⋅s [1] :25 |
| Header7: | Conversions |
| Data8: | |
| in ... | ... corresponds to ... |
| Label9: | SI units |
| Data9: | |
| Data10: | statamperes ≈ [2] :16 |
The abampere (abA), also called the biot (Bi) after Jean-Baptiste Biot, is the derived electromagnetic unit of electric current in the emu-cgs system of units (electromagnetic cgs). One abampere corresponds to ten amperes in the SI system of units. An abampere of current in a circular path of one centimeter radius produces a magnetic field of 2π oersteds at the center of the circle.
The name abampere was introduced by Kennelly in 1903 as a short name for the long name (absolute) electromagnetic cgs unit of current that was in use since the adoption of the cgs system in 1875.[3] The abampere was coherent with the emu-cgs system, in contrast to the ampere, the practical unit of current that had been adopted too in 1875.
The emu-cgs (or "electromagnetic cgs") units are one of several systems of electromagnetic units within the centimetre–gram–second system of units; others include esu-cgs, Gaussian units, and Heaviside–Lorentz units. In these other systems, the abampere is not one of the units; the "statcoulomb per second" or statampere is used instead.
The other units in this system related to the abampere are: