SI Measurement System Chart - NIST · YZ EP TG Mk hd ad c m µ np fa zy PREFIXES SI symbols are the...
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yotta 1 000 000 000 000 000 000 000 000 1 000 000 000 000 000 000 000 1 000 000 000 000 000 000 1 000 000 000 000 000 1 000 000 000 000 1 000 000 000 1 000 000 1 000 100 10 0.1 0.01 0.001 0.000 001 0.000 000 001 0.000 000 000 001 0.000 000 000 000 001 0.000 000 000 000 000 001 0. 000 000 000 000 000 000 001 0. 000 000 000 000 000 000 000 001 1 zetta exa peta tera giga mega kilo hecto deka deci centi milli micro nano pico femto atto zepto yocto 10 24 10 21 10 18 10 15 10 12 10 9 10 6 10 3 10 2 10 1 10 0 10 -1 10 -2 10 -3 10 -6 10 -9 10 -12 10 -15 10 -18 10 -21 10 -24 Y Z E P T G M k h da d c m μ n p f a z y PREFIXES SI symbols are the same worldwide, regardless of the spelling, language, or alphabet. Prefix symbols are used with a unit symbol to represent smaller or larger units by factors that are powers of 10. NIST SP 304A July 2017 [email protected] www.nist.gov/metric www.nist.gov The International System of Units (SI) is made up of 7 base units, featured on this chart with their Measurement League counterparts. The SI, commonly known as the metric system, is easy to use. G U A R D IA N S O F T H E S I AMPERE (A) ELECTRIC CURRENT 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 apart in vacuum, would produce between these conductors a force equal to 2 x 10 -7 newton per meter of length. CANDELA (cd) LUMINOUS INTENSITY KILOGRAM (kg) MASS The kilogram is the unit of mass, equal to the mass of the international prototype of the kilogram (IPK). KELVIN (K) TEMPERATURE The kelvin, unit of thermodynamic temperature, is the fraction 73. 16 of the thermodynamic temperature of the triple point of water. MOLE (mol) AMOUNT OF SUBSTANCE 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. SECOND (s) TIME The second is the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom. METER (m) LENGTH The meter is the length of the path traveled by light in vacuum during a time interval of 99 792 458 of a second. The candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency 540 x 10 12 hertz and that has a radiant intensity in that direction of 83 watt per steradian. This publication is free of charge from: https://doi. org/10.6028/NIST. SP.304a-2017
Transcript of SI Measurement System Chart - NIST · YZ EP TG Mk hd ad c m µ np fa zy PREFIXES SI symbols are the...
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Y Z E P T G M k h da d c m µ n p f a z y
PREFIXES
SI symbols are the same worldwide, regardless of the spelling, language, or alphabet. Prefix symbols are used with a unit symbol to represent
smaller or larger units by factors that are powers of 10.
NIST SP 304A July [email protected]/metric
www.nist.gov
The International System of Units (SI) is made up of 7 base units, featured on this chart with their Measurement League counterparts. The SI, commonly known as the metric system, is easy to use.
GUARDIANS OF THE SI
AMPERE (A) ELECTRIC CURRENT 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 apart in vacuum, would produce between these conductors a force equal to 2 x 10-7 newton per meter of length.
CANDELA (cd) LUMINOUS INTENSITY
KILOGRAM (kg) MASS The kilogram is the unit of mass, equal to the mass of the international prototype of the kilogram (IPK).
KELVIN (K) TEMPERATUREThe kelvin, unit of thermodynamic temperature, is the fraction 1/273.16 of the thermodynamic temperature of the triple point of water.
MOLE (mol) AMOUNT OF SUBSTANCE 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.
SECOND (s) TIME The second is the duration of9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom.
METER (m) LENGTH 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.
The candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency 540 x 1012 hertz and that has a radiant intensity in that direction of 1/683 watt per steradian.
This publication is free of charge from: https://doi.org/10.6028/NIST.SP.304a-2017
