Where m = 1 kg and a = 1 m/s2, thus F = 1 kg The international unit of force is thus obtained by applying Newton's Law: force = mass x acceleration Base SI units Base SI unit Name Symbol Length l meter m Mass mkilogramkg Time t second s Electric current I ampere A Thermodynamic temperatureT kelvin K Amount of substance n mole mol Luminous intensity I candela cd Base quantity and symbolsĪll other quantities and units are derived from the base quantities and base units.
SI units comprise the seven base SI units and coherent units derived from these base Sl units using a numerical factor of 1. The system is laid down in ISO 31 and ISO 1000 (ISO: International Organization for Standardization) and for Germany in DIN 1301 (DIN: Deutsches Institut für Normung – German Institute for Standardization).
SI denotes 'Système International d'Unités' (International System of Units). Basic principles, Physics Quantities and units SI units
