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
Eotvos (unit) Eotvos (unit) The eotvos is a unit of acceleration divided by distance that was used in conjunction with the older centimeter-gram-second system of units (cgs). The eotvos is defined as 1/1,000,000,000 galileos per centimetre. The symbol of the eotvos unit is E. In SI units or in cgs units, 1 eotvos = 10 second. The gravitational gradient of the Earth, that is, the change in the gravitational acceleration vector from one point on the Earth’s surface to another, is customarily measured in units of eotvos. The Earth's gravity gradient is dominated by the component due to Earth's near-spherical shape, which