SI derived unit Until 1995, the SI classified the radian and the steradian as "supplementary units", but this designation was abandoned and the units were grouped as derived units. SI derived unit SI derived units are units of measurement derived from the seven base units specified by the International System of Units (SI). They are either dimensionless or can be expressed as a product of one or more of the base units, possibly scaled by an appropriate power of exponentiation. The SI has special names for 22 of these derived units (for example, hertz, the SI unit of measurement of frequency), but the
Maxwell (unit) non-SI unit. That is, one maxwell is the total flux across a surface of one square centimetre perpendicular to a magnetic field of strength one gauss. The weber is the related SI unit of magnetic flux, which was defined in 1946. Maxwell (unit) The maxwell (symbol: Mx) is the CGS (centimetre-gram-second) unit of magnetic flux (). The unit name honours James Clerk Maxwell, who presented a unified theory of electromagnetism. The "maxwell" was recommended as a CGS unit at the International Electrical Congress held in 1900 at Paris. This practical unit was previously called a "line", reflecting Faraday's conception of