base SI unit Comparison Table

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base SI unit comparison table

Subject has absolute zero is named after has definition has historical origin has symbol has triple point of water has approval agency has synonym requires qualification has approval date convert to Celsiu has consequence is a unit of

ampere constant current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross-section, and placed 1 meter apart in vacuum, would produce between these conductors a force equal to 2 × 10^-7 newton per meter of length A fixes the magnetic constant (permeability of vacuum) at exactly 4 × 10^-7 H · m^-1 current

candela the luminous intensity in a given direction, of a source that emits monochromatic radiation of frequency 540 × 10¹² hertz and that has a radiant intensity in that direction of 1/683 watt per steradian in 1933 it was based on the luminous emission of a blackbody at the freezing temperature of platinum (2045 K) cd 13th CGPM 1967 luminous intensity

Kelvin 0 Lord Kelvin (1824-1907) Unit of thermodynamic temperature, is the fraction 1/273.16 of the thermodynamic temperature of the triple point of water K 273.16 16th CGPM absolute 1968 subtract 273.15 temperature

kilogram Unit of mass equal to the international prototype of the kilogram at the end of the 18th century, a kilogram was the mass of a cubic decimeter of water kg mass

meter length of the path travelled by light in vacuum during a time interval of 1/299 792 458 of a second chosen in 1791 by the French Academy of Sciences as 10^-7 of the length of the meridian through Paris from pole to the equator m 11th CGPM 1960 fixes the speed of light in vacuum at exactly 299792458 m·s^-1 length

mole amount of substance of a system which contains as many elementary entities as there are atoms in 0.012 kilogram of carbon 12 mol 14th CGPM elementary entities must be specified and may be atoms, molecules, ions, electrons, other particles, or specified groups of such particles 1971 amount of substance

second duration of 9192631770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom was defined originally as the fraction 1/86400 of the mean solar day s time

Subject	has absolute zero	is named after	has definition	has historical origin	has symbol	has triple point of water	has approval agency	has synonym	requires qualification	has approval date	convert to Celsiu	has consequence	is a unit of
ampere			constant current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross-section, and placed 1 meter apart in vacuum, would produce between these conductors a force equal to 2 × 10^-7 newton per meter of length		A							fixes the magnetic constant (permeability of vacuum) at exactly 4 × 10^-7 H · m^-1	current
candela			the luminous intensity in a given direction, of a source that emits monochromatic radiation of frequency 540 × 10¹² hertz and that has a radiant intensity in that direction of 1/683 watt per steradian	in 1933 it was based on the luminous emission of a blackbody at the freezing temperature of platinum (2045 K)	cd		13th CGPM			1967			luminous intensity
Kelvin	0	Lord Kelvin (1824-1907)	Unit of thermodynamic temperature, is the fraction 1/273.16 of the thermodynamic temperature of the triple point of water		K	273.16	16th CGPM	absolute		1968	subtract 273.15		temperature
kilogram			Unit of mass equal to the international prototype of the kilogram	at the end of the 18th century, a kilogram was the mass of a cubic decimeter of water	kg								mass
meter			length of the path travelled by light in vacuum during a time interval of 1/299 792 458 of a second	chosen in 1791 by the French Academy of Sciences as 10^-7 of the length of the meridian through Paris from pole to the equator	m		11th CGPM			1960		fixes the speed of light in vacuum at exactly 299792458 m·s^-1	length
mole			amount of substance of a system which contains as many elementary entities as there are atoms in 0.012 kilogram of carbon 12		mol		14th CGPM		elementary entities must be specified and may be atoms, molecules, ions, electrons, other particles, or specified groups of such particles	1971			amount of substance
second			duration of 9192631770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom	was defined originally as the fraction 1/86400 of the mean solar day	s								time

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