AND 'DO SOME GOOD REVIEW ON FUNDAMENTAL
, IN PARTICULAR
SI (International System)
DEFINITIONS AND UNITS ' MEASURING
LENGTH: METRO SYMBOL
m Weight: kg kilogram
Time: s second
Current: Ampere
A Thermodynamic temperature: Kelvin K
Amount of substance mole mol Luminous intensity
: candle cd
take for the completeness definitions
Metro: length of the path taken by light in vacuum
, in a time of
1 / 299792458 of a second
(the denominator we have the speed of light in meters)
In Italy there are samples in the Institute of Metrology Gustavo
Colonnetti, CNR, Torino
mass: mass the international prototype kept at
Pavillon de Breteuil (Sèvres)
in Italy while the sample is kept at the M.
of Industry and Commerce and 'Arts and Crafts in Rome.
Second time interval that contains
9192631770 periods of radiation corresponding to the transition between two hyperfine levels
the ground state of cesium 133. In Italy
reference is an atomic clock of the Institute G.
Ferraris in Turin
Amps. intensità di electric current, kept constant in the two conductors
straight, parallel, long innfinita,
negligible circular cross-section and placed at a distance of 1 meter
each other in a vacuum, it produces between the conductors of the power
2 / 10000000 N per meter of length.
(the Italian champion is always at the Ferraris)
Kelvin: fraction 1 / 273, 16 of the thermodynamic temperature of the triple point of water
mole (omitted) exercise for the reader
candle (omitted)
Derived quantities
Frequency, SI hertz (symbol Hz):
frequency of a periodic phenomenon whose period is 1 second
ps (add another card in the remaining)
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