The abohm is the

derived Derive may refer to: * Derive (computer algebra system), a commercial system made by Texas Instruments * ''Dérive'' (magazine), an Austrian science magazine on urbanism *Dérive, a psychogeographical concept See also * *Derivation (disambiguatio ...

unit of electrical resistance in the emu-cgs ''(centimeter-gram-second)'' system of units (emu stands for "electromagnetic units"). One abohm corresponds to 10⁻⁹

ohm Ohm (symbol Ω) is a unit of electrical resistance named after Georg Ohm. Ohm or OHM may also refer to: People * Georg Ohm (1789–1854), German physicist and namesake of the term ''ohm'' * Germán Ohm (born 1936), Mexican boxer * Jörg Ohm (b ...

s in the SI system of units, which is a nanoohm. The emu-cgs (or "electromagnetic cgs") units are one of several systems of electromagnetic units within the

centimetre gram second system of units 330px, Different lengths as in respect to the Electromagnetic spectrum, measured by the Metre and its deriveds scales. The Microwave are in-between 1 meter to 1 millimeter. A centimetre (international spelling) or centimeter (American spellin ...

; others include esu-cgs,

Gaussian units Gaussian units constitute a metric system of physical units. This system is the most common of the several electromagnetic unit systems based on cgs (centimetre–gram–second) units. It is also called the Gaussian unit system, Gaussian-cgs unit ...

, and

Heaviside–Lorentz units Heaviside–Lorentz units (or Lorentz–Heaviside units) constitute a system of units (particularly electromagnetic units) within CGS, named for Hendrik Antoon Lorentz and Oliver Heaviside. They share with CGS-Gaussian units the property that th ...

. In these other systems, the abohm is ''not'' one of the units. When a current of one

abampere 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 ...

(1 abA) flows through a resistance of 1 abohm, the resulting potential difference across the component is one

abvolt The abvolt (abV) is the unit of potential difference in the CGS-EMU system of units. It corresponds to in the SI system and 1/ statvolt ≈ in the CGS-ESU system. A potential difference of 1 abV will drive a current of one abampere through ...

(1 abV). The name abohm was introduced by Kennelly in 1903 as a short name for the long name ''(absolute) electromagnetic cgs unit of resistance'' that was in use since the adoption of the cgs system in 1875.A.E. Kennelly (1903
"Magnetic units and other subjects that might occupy attention at the next international electrical congress"
''20th Annual Convention of the American Institute of Electrical Engineers, 1903'' The abohm was

coherent Coherence, coherency, or coherent may refer to the following: Physics * Coherence (physics), an ideal property of waves that enables stationary (i.e. temporally and spatially constant) interference * Coherence (units of measurement), a deri ...

with the emu-cgs system, in contrast to the ohm, the practical unit of resistance that had been adopted too in 1875.

References

* ''The McGraw Hill Dictionary Of Scientific and Technical Terms'', . Units of electrical resistance Centimetre–gram–second system of units {{measurement-stub