Base unit

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Base Units Definition

Unit	Symbol	Definition
meter	m	The meter is the length of the path traveled by light in vacuum during a time interval of 1/299,792,458 of a second
kilogram	kg	The kilogram is the unit of mass, it is equal to the mass of the international prototype of the kilogram
second	s	The second is the duration of 9 192 631 770 periods of radiation corresponding to the transition between the two hyperfine levels of the ground state of the Cesium 133 atom
ampere	A	The ampere is that constant current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross-section, and placed 1 meter a part in vacuum, would produce between these conductors a force equal to 2E-7 newton's per meter of length.
kelvin	K	The kelvin , unit of thermodynamic temperature, is the fraction 1/273.16 of the thermodynamic temperature of the triple point of water
candela	cd	The candela is the luminous intensity , in a given direction of a source that emits monochromatic radiation of frequency 540E12 hertz and that has a radiant intensity in that direction of 1/683 watt per steradian
mole	mol	The mole is the amount of substance of a system which contains as many elementary entities as there are atoms in 0.012 kilogram of Carbon 12 . Note: When the mole is used, the elementary entities must be specified and may be atoms, molecules, ions, electrons, other particles, or specified groups of such particles.