Carl Friedrich Gauß in 1828, aged 50 years old

The gauss (symbol: G, sometimes Gs) is a unit of measurement of magnetic flux density, B (also known as magnetic induction or magnetic field). The unit is part of the Gaussian system of units, which inherited it from the older centimetre–gram–second electromagnetic units (CGS-EMU) system. It was named after the German mathematician and physicist Carl Friedrich Gauss in 1936. One gauss is defined as one maxwell per square centimetre.

As the centimetre–gram–second system of units (cgs system) has been superseded by the International System of Units (SI), the use of the gauss has been deprecated by the standards bodies, but is still regularly used in various subfields of science, and preferred in astrophysics. The SI unit for magnetic flux density is the tesla (symbol T), which corresponds to 10,000gauss.

Name, symbol, and metric prefixes

Although not a component of the International System of Units, the usage of the gauss generally follows the rules for SI units. Since the name is derived from a person's name, its symbol is the uppercase letter "G". When the unit is spelled out, it is written in lowercase ("gauss"), unless it begins a sentence.[citation needed] The gauss may be combined with metric prefixes,such as in milligauss, mG (or mGs), or kilogauss, kG (or kGs).

Unit conversions

1 G = M x ⋅ c m − 2 = g B i ⋅ s 2 corresponds to 10 − 4 T = 10 − 4 k g A ⋅ s 2 {\displaystyle {\begin{aligned}1\,{\rm {G}}&={\rm {Mx}}{\cdot }{\rm {cm}}^{-2}={\frac {\rm {g}}{{\rm {Bi}}{\cdot }{\rm {s}}^{2}}}\\&{\text{ corresponds to }}10^{-4}\,{\rm {T}}=10^{-4}{\frac {\rm {kg}}{{\rm {A}}{\cdot }{\rm {s^{2}}}}}\end{aligned}}}

The gauss is the unit of magnetic flux density B in the system of Gaussian units and is equal to Mx/cm2 or g/Bi/s2, while the oersted is the unit of H-field. One tesla (T) corresponds to 104gauss, and one ampere (A) per metre corresponds to 4π×10−3 oersted, both with an uncertainty of 8x10−11.

The 8th edition of the International System of Units specified that 1 gauss equalled 10−4 tesla. After the 2019 revision of the SI included a change to the definition of the base unit ampere, the 9th edition of the standard did not list any conversion factor between gauss and tesla.

Typical values

See also

Notes