The international system of units known as the SI units is based on the seven basic units: Mass, Length, Time, Electric current, Temperature, Amount of substance and Luminous intensity.
The basic seven quantities from which other units are derived are tabulated below:
|Amount of substance||mole||mol|
The radian and steradian may also be treated as basic units.
These are multiplications and divisions of the basic units to form derived units. Some of these derived units are listed below along with their derivation in terms of basic units:
|Derived quantity||Name||Symbol||Basic Unit Derivation|
|Magnetic Flux Density||tesla||T||kgs-2A-1|
1866 The use of the metric system in the United States was legalized by Congress but was not made obligatory.