Search results
Results from the WOW.Com Content Network
The International System of Units, internationally known by the abbreviation SI (from French Système international d'unités), is the modern form of the metric system and the world's most widely used system of measurement. It is the only system of measurement with official status in nearly every country in the world, employed in science ...
The SI base units form a set of mutually independent dimensions as required by dimensional analysis commonly employed in science and technology. [ citation needed ] The names and symbols of SI base units are written in lowercase, except the symbols of those named after a person, which are written with an initial capital letter.
Unit system Domain Derivation Unit name Unit symbol Dimension symbol Quantity name Definition In SI base units In other SI units SI: Physics: Basic
The SI system has been adopted as the official system of weights and measures by most countries in the world. A notable outlier is the United States (US). Although used in some contexts, the US has resisted full adoption; continuing to use "a conglomeration of basically incoherent measurement systems". [2]
The exact modern SI definition is "[The second] is defined by taking the fixed numerical value of the cesium frequency, Δν Cs, the unperturbed ground-state hyperfine transition frequency of the cesium 133 atom, to be 9 192 631 770 when expressed in the unit Hz, which is equal to s −1."
The current international standard for the metric system is the International System of Units (Système international d'unités or SI). It is a system in which all units can be expressed in terms of seven units. The units that serve as the SI base units are the metre, kilogram, second, ampere, kelvin, mole, and candela.
SI derived unit Dimension Comments Absement: A: Measure of sustained displacement: the first integral with respect to time of displacement m⋅s L T: vector Acceleration: a →: Rate of change of velocity per unit time: the second time derivative of position m/s 2: L T −2: vector Angular acceleration: ω a: Change in angular velocity per unit ...
Main page; Contents; Current events; Random article; About Wikipedia; Contact us; Pages for logged out editors learn more