SI Reference Point - Units and Prefixes
type: Ontology
license: igo
comment: Ontology, part of the SI Reference Point, covering measurement units (SI base units and SI units with special names) and prefixes.
comment: The SI Reference Point Ontology developed by the BIPM is licensed under CC-BY-3.0-IGO. You are free to share (copy and redistribute the material in any medium or format) and adapt (remix, transform, and build upon the material) for any purpose, even commercially, for any purpose, even commercially. The licensor cannot revoke these freedoms as long as you follow the license terms. You must give appropriate credit (by using the original ontology IRI for the whole ontology and original term IRIs for individual terms), provide a link to the license, and indicate if any changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
comment: L'ontologie SI Reference Point developpée par le BIPM est sous licence CC-BY-3.0-IGO. Vous êtes autorisés à partager (copier, distribuer et communiquer le matériel par tous moyens et sous tous formats) et adapter (remixer, transformer et créer à partir du matériel) pour toute utilisation, y compris commerciale. L'Offrant ne peut retirer les autorisations concédées par la licence tant que vous appliquez les termes de cette licence. Vous devez créditer l'oeuvre (en utilisant l'IRI de l'ontologie originale pour l'ontologie entière et les IRIs originaux des termes individuels), intégrer un lien vers la licence et indiquer si des modifications ont été effectuées à l'oeuvre. Vous devez indiquer ces informations par tous les moyens raisonnables, sans toutefois suggérer que l'offrant vous soutient ou soutient la façon dont vous avez utilisé son Oeuvre. @fr

arcminute
type: nonSIUnit
has symbol: ′
has unit type as string: Non-SI unit accepted for use with the SI
has unit type as string: Unité en dehors du SI dont l'usage est accepté avec le SI @fr
in other SI units: UnitMultiple
  has numeric factor: 0.000290888208665722
  has numeric factor as string: (π \; / \; 10800)
  has unit term: radian
is unit of qty kind: ANGP
prefix restriction: true

arcsecond
type: nonSIUnit
preferred label: arcseconde @fr
has symbol: ″
has unit type as string: Non-SI unit accepted for use with the SI
has unit type as string: Unité en dehors du SI dont l'usage est accepté avec le SI @fr
in other SI units: UnitMultiple
  has numeric factor: 4.84813681109536e-06
  has numeric factor as string: (π \; / \; 648000)
  has unit term: radian
is unit of qty kind: ANGP
prefix restriction: true

astronomical unit
type: nonSIUnit
preferred label: unité astronomique @fr
has symbol: au
has unit type as string: Non-SI unit accepted for use with the SI
has unit type as string: Unité en dehors du SI dont l'usage est accepté avec le SI @fr
in other SI units: UnitMultiple
  has numeric factor: 149597870700
  has numeric factor as string: 149\:597\:870\:700
  has unit term: metre
is unit of qty kind: LENG
prefix restriction: true

becquerel
type: SISpecialNamedUnit
has defining resolution: CGPM15-Res8
has symbol: Bq
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitPower
  has numeric exponent: -1
  has unit base: second
is unit of qty kind: ARRN
prefix restriction: false

bel
type: nonSIUnit
has symbol: B
has unit type as string: Non-SI unit accepted for use with the SI
has unit type as string: Unité en dehors du SI dont l'usage est accepté avec le SI @fr
is unit of qty kind: RLGB
prefix restriction: false

dalton
type: nonSIUnit
has symbol: Da
has unit type as string: Non-SI unit accepted for use with the SI
has unit type as string: Unité en dehors du SI dont l'usage est accepté avec le SI @fr
in other SI units: UnitMultiple
  has numeric factor: 1.6605390666e-27
  has numeric factor as string: 1.660\:539\:066\:60(50) \times 10^{-27}
  has unit term: kilogram
is unit of qty kind: MASS
prefix restriction: false

day
type: nonSIUnit
preferred label: jour @fr
has symbol: d
has unit type as string: Non-SI unit accepted for use with the SI
has unit type as string: Unité en dehors du SI dont l'usage est accepté avec le SI @fr
in other SI units: UnitMultiple
  has numeric factor: 86400
  has numeric factor as string: 86\:400
  has unit term: second
is unit of qty kind: TIME
prefix restriction: true

degree
type: nonSIUnit
preferred label: degré @fr
has symbol: °
has unit type as string: Non-SI unit accepted for use with the SI
has unit type as string: Unité en dehors du SI dont l'usage est accepté avec le SI @fr
in other SI units: UnitMultiple
  has numeric factor: 0.0174532925199433
  has numeric factor as string: (π \; / \; 180)
  has unit term: radian
is unit of qty kind: ANGP
prefix restriction: true

degree Celsius
type: SISpecialNamedUnit
preferred label: degré Celsius @fr
has defining resolution: CGPM9-Res7
has symbol: ℃
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: kelvin
is unit of qty kind: TEMC
prefix restriction: false

electronvolt
type: nonSIUnit
preferred label: électronvolt @fr
has symbol: eV
has unit type as string: Non-SI unit accepted for use with the SI
has unit type as string: Unité en dehors du SI dont l'usage est accepté avec le SI @fr
in other SI units: UnitMultiple
  has numeric factor: 1.602176634e-19
  has numeric factor as string: 1.602\:176\:634 \times 10^{-19}
  has unit term: joule
is unit of qty kind: ENGY
prefix restriction: false

farad
type: SISpecialNamedUnit
has defining resolution: CGPM9-Res7
has symbol: F
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitProduct
  has left unit term: UnitPower
    has numeric exponent: -1
    has unit base: kilogram
  has right unit term: UnitProduct
    has left unit term: UnitPower
      has numeric exponent: -2
      has unit base: metre
    has right unit term: UnitProduct
      has left unit term: UnitPower
        has numeric exponent: 4
        has unit base: second
      has right unit term: UnitPower
        has numeric exponent: 2
        has unit base: ampere
in other SI units: UnitProduct
  has left unit term: coulomb
  has right unit term: UnitPower
    has numeric exponent: -1
    has unit base: volt
is unit of qty kind: ELCA
prefix restriction: false

gray
type: SISpecialNamedUnit
has defining resolution: CGPM15-Res9
has symbol: Gy
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitProduct
  has left unit term: UnitPower
    has numeric exponent: 2
    has unit base: metre
  has right unit term: UnitPower
    has numeric exponent: -2
    has unit base: second
in other SI units: UnitProduct
  has left unit term: joule
  has right unit term: UnitPower
    has numeric exponent: -1
    has unit base: kilogram
is unit of qty kind: ABDO
is unit of qty kind: KRMA
prefix restriction: false

hectare
type: nonSIUnit
has symbol: ha
has unit type as string: Non-SI unit accepted for use with the SI
has unit type as string: Unité en dehors du SI dont l'usage est accepté avec le SI @fr
in other SI units: UnitMultiple
  has numeric factor: 10000
  has numeric factor as string: 10^{4}
  has unit term: UnitPower
    has numeric exponent: 2
    has unit base: metre
is unit of qty kind: AREA
prefix restriction: true

henry
type: SISpecialNamedUnit
has defining resolution: CGPM9-Res7
has symbol: H
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitProduct
  has left unit term: kilogram
  has right unit term: UnitProduct
    has left unit term: UnitPower
      has numeric exponent: 2
      has unit base: metre
    has right unit term: UnitProduct
      has left unit term: UnitPower
        has numeric exponent: -2
        has unit base: second
      has right unit term: UnitPower
        has numeric exponent: -2
        has unit base: ampere
in other SI units: UnitProduct
  has left unit term: weber
  has right unit term: UnitPower
    has numeric exponent: -1
    has unit base: ampere
is unit of qty kind: ELIN
prefix restriction: false

hertz
type: SISpecialNamedUnit
has defining resolution: CGPM9-Res7
has symbol: Hz
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitPower
  has numeric exponent: -1
  has unit base: second
is unit of qty kind: FREQ
prefix restriction: false

hour
type: nonSIUnit
preferred label: heure @fr
has symbol: h
has unit type as string: Non-SI unit accepted for use with the SI
has unit type as string: Unité en dehors du SI dont l'usage est accepté avec le SI @fr
in other SI units: UnitMultiple
  has numeric factor: 3600
  has numeric factor as string: 3600
  has unit term: second
is unit of qty kind: TIME
prefix restriction: true

katal
type: SISpecialNamedUnit
has defining resolution: CGPM21-Res12
has symbol: kat
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitProduct
  has left unit term: mole
  has right unit term: UnitPower
    has numeric exponent: -1
    has unit base: second
is unit of qty kind: CATA
prefix restriction: false

litre
type: nonSIUnit
has alt symbol: l
has symbol: L
has unit type as string: Non-SI unit accepted for use with the SI
has unit type as string: Unité en dehors du SI dont l'usage est accepté avec le SI @fr
in other SI units: UnitMultiple
  has numeric factor: 0.001
  has numeric factor as string: 0.001
  has unit term: UnitPower
    has numeric exponent: 3
    has unit base: metre
is unit of qty kind: VOLU
prefix restriction: false

lux
type: SISpecialNamedUnit
has defining resolution: CGPM11-Res12
has symbol: lx
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitProduct
  has left unit term: candela
  has right unit term: UnitProduct
    has left unit term: steradian
    has right unit term: UnitPower
      has numeric exponent: -2
      has unit base: metre
in other SI units: UnitProduct
  has left unit term: lumen
  has right unit term: UnitPower
    has numeric exponent: -2
    has unit base: metre
is unit of qty kind: ILLU
prefix restriction: false

minute
type: nonSIUnit
has symbol: min
has unit type as string: Non-SI unit accepted for use with the SI
has unit type as string: Unité en dehors du SI dont l'usage est accepté avec le SI @fr
in other SI units: UnitMultiple
  has numeric factor: 60
  has numeric factor as string: 60
  has unit term: second
is unit of qty kind: TIME
prefix restriction: true

neper
type: nonSIUnit
preferred label: néper @fr
has symbol: Np
has unit type as string: Non-SI unit accepted for use with the SI
has unit type as string: Unité en dehors du SI dont l'usage est accepté avec le SI @fr
is unit of qty kind: RLGN
prefix restriction: true

ohm
type: SISpecialNamedUnit
has defining resolution: CGPM9-Res7
has symbol: Ω
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitProduct
  has left unit term: kilogram
  has right unit term: UnitProduct
    has left unit term: UnitPower
      has numeric exponent: 2
      has unit base: metre
    has right unit term: UnitProduct
      has left unit term: UnitPower
        has numeric exponent: -3
        has unit base: second
      has right unit term: UnitPower
        has numeric exponent: -2
        has unit base: ampere
in other SI units: UnitProduct
  has left unit term: volt
  has right unit term: UnitPower
    has numeric exponent: -1
    has unit base: ampere
is unit of qty kind: ELRE
prefix restriction: false

one
type: MeasurementUnit
preferred label: un @fr
has symbol: 1
prefix restriction: true

pascal
type: SISpecialNamedUnit
has defining resolution: CGPM14-Decl
has symbol: Pa
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitProduct
  has left unit term: kilogram
  has right unit term: UnitProduct
    has left unit term: UnitPower
      has numeric exponent: -1
      has unit base: metre
    has right unit term: UnitPower
      has numeric exponent: -2
      has unit base: second
in other SI units: UnitProduct
  has left unit term: newton
  has right unit term: UnitPower
    has numeric exponent: -2
    has unit base: metre
is unit of qty kind: PRES
prefix restriction: false

siemens
type: SISpecialNamedUnit
has defining resolution: CGPM14-Decl
has symbol: S
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitProduct
  has left unit term: UnitPower
    has numeric exponent: -1
    has unit base: kilogram
  has right unit term: UnitProduct
    has left unit term: UnitPower
      has numeric exponent: -2
      has unit base: metre
    has right unit term: UnitProduct
      has left unit term: UnitPower
        has numeric exponent: 3
        has unit base: second
      has right unit term: UnitPower
        has numeric exponent: 2
        has unit base: ampere
in other SI units: UnitProduct
  has left unit term: ampere
  has right unit term: UnitPower
    has numeric exponent: -1
    has unit base: volt
is unit of qty kind: ELCO
prefix restriction: false

sievert
type: SISpecialNamedUnit
has defining resolution: CGPM16-Res5
has symbol: Sv
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitProduct
  has left unit term: UnitPower
    has numeric exponent: 2
    has unit base: metre
  has right unit term: UnitPower
    has numeric exponent: -2
    has unit base: second
in other SI units: UnitProduct
  has left unit term: joule
  has right unit term: UnitPower
    has numeric exponent: -1
    has unit base: kilogram
is unit of qty kind: DOEQ
prefix restriction: false

tesla
type: SISpecialNamedUnit
has defining resolution: CGPM11-Res12
has symbol: T
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitProduct
  has left unit term: kilogram
  has right unit term: UnitProduct
    has left unit term: UnitPower
      has numeric exponent: -2
      has unit base: second
    has right unit term: UnitPower
      has numeric exponent: -1
      has unit base: ampere
in other SI units: UnitProduct
  has left unit term: weber
  has right unit term: UnitPower
    has numeric exponent: -2
    has unit base: metre
is unit of qty kind: MGFD
prefix restriction: false

tonne
type: nonSIUnit
has symbol: t
has unit type as string: Non-SI unit accepted for use with the SI
has unit type as string: Unité en dehors du SI dont l'usage est accepté avec le SI @fr
in other SI units: UnitMultiple
  has numeric factor: 1000
  has numeric factor as string: 1000
  has unit term: kilogram
is unit of qty kind: MASS
prefix restriction: true

ampere1948note1
type: DefinitionNote
has note index: 1
has note text: The expression « MKS unit of force » which occurs in the original text has been replaced here by «newton», a name adopted for this unit by the 9th CGPM (1948, Resolution 7).
has note text: L’expression « unité MKS de force » qui figure dans le texte original de 1946 a été remplacée ici par « newton », nom adopté pour cette unité par la 9ᵉ CGPM (1948, Résolution 7). @fr

ampere2018note1
type: DefinitionNote
has note index: 1
has note text: This definition implies the exact relation ${{e}} = {{1.602\:176\:634 \times 10^{-19}}}\ {{\rm{A}}\ {\rm{s}}}$. Inverting this relation gives an exact expression for the unit ampere in terms of the defining constants ${e}$ and $\Delta\nu_{\rm{Cs}}$: $$1\;{\rm{A}} = \left(\frac{{e}}{{1.602\:176\:634 \times 10^{-19}}}\right)\ {{\rm{s}}^{-1}}$$ which is equal to $$1\;{\rm{A}} = \frac{1}{({9\:192\:631\:770})({1.602\:176\:634 \times 10^{-19}})}\,{\Delta\nu_{\rm{Cs}}}\;{{e}} \approx {{6.789\:6868 \times 10^{8}}} {\Delta\nu_{\rm{Cs}}}\;{{e}}$$.
has note text: Cette définition implique la relation exacte ${{e}} = {{1.602\:176\:634 \times 10^{-19}}}\ {{\rm{A}}\ {\rm{s}}}$. En inversant cette relation, l’ampère est exprimé en fonction des constante ${e}$ et $\Delta\nu_{\rm{Cs}}$ : $$1\;{\rm{A}} = \left(\frac{{e}}{{1.602\:176\:634 \times 10^{-19}}}\right)\ {{\rm{s}}^{-1}}$$ relation identique à $$1\;{\rm{A}} = \frac{1}{({9\:192\:631\:770})({1.602\:176\:634 \times 10^{-19}})}\,{\Delta\nu_{\rm{Cs}}}\;{{e}} \approx {{6.789\:6868 \times 10^{8}}} {\Delta\nu_{\rm{Cs}}}\;{{e}}$$. @fr

ampere2018note2
type: DefinitionNote
has note index: 2
has note text: The effect of this definition is that one ampere is the electric current corresponding to the flow of $1/({1.602\:176\:634 \times 10^{-19}})$ elementary charges per second.
has note text: Il résulte de cette définition qu’un ampère est le courant électrique correspondant au flux de $1/({1.602\:176\:634 \times 10^{-19}})$ charges élémentaires par seconde. @fr

ampere2018note3
type: DefinitionNote
has note index: 3
has note text: The previous definition of the ampere was based on the force between two current carrying conductors and had the effect of fixing the value of the vacuum magnetic permeability $\mu_{0}$ (also known as the magnetic constant) to be exactly ${{4\pi \times 10^{-7}}}\ {\rm{H}\ \rm{m}}^{-1} = {4\pi \times 10^{-7}}\ \rm{N}\ \rm{A}^{-2}$, where $\rm{H}$ and $\rm{N}$ denote the coherent derived units henry and newton, respectively. The new definition of the ampere fixes the value of ${e}$ instead of $\mu_{0}$. As a result, $\mu_{0}$ must be determined experimentally.
has note text: La précédente définition de l’ampère, fondée sur la force produite entre deux conducteurs traversés par du courant, fixait la valeur de la perméabilité magnétique du vide $\mu_{0}$ (également connue sous le nom de constante magnétique) à exactement ${{4\pi \times 10^{-7}}}\ {\rm{H}\ \rm{m}}^{-1} = {4\pi \times 10^{-7}}\ \rm{N}\ \rm{A}^{-2}$, $\rm{H}$ et $\rm{N}$ représentant les unités dérivées cohérentes « henry » et « newton », respectivement. La nouvelle définition de l’ampère fixe la valeur numérique de ${e}$ et non plus celle de $\mu_{0}$. Par conséquent, $\mu_{0}$ doit désormais être déterminée de façon expérimentale. @fr

ampere2018note4
type: DefinitionNote
has note index: 4
has note text: It also follows that since the vacuum electric permittivity $\varepsilon_{0}$ (also known as the electric constant), the characteristic impedance of vacuum ${Z_{0}}$, and the admittance of vacuum ${Y_{0}}$ are equal to $1/{\mu_{0}}{c}^{2}$, ${\mu_{0}}{c}$, and $1/{\mu_{0}}{c}$, respectively the values of $\varepsilon_{0}$, ${Z_{0}}$ and ${Y_{0}}$ must now also be determined experimentally, and are affected by the same relative standard uncertainty as $\mu_{0}$ since $c$ is exactly known. The product ${\varepsilon_{0}} {\mu_{0}} = 1/{c}^{2}$ and quotient ${{Z_{0}}}/{\mu_{0}} = {c}$ remain exact. At the time of adopting the present definition of the ampere, $\mu_{0}$ was equal to ${4\pi \times 10^{-7}\ \rm{H}/\rm{m}}$ with a relative standard uncertainty of ${2.3 \times 10^{-10}}$.
has note text: Ainsi, comme la permittivité diélectrique du vide $\varepsilon_{0}$ (également connue sous le nom de constante électrique), l’impédance du vide caractéristique ${Z_{0}}$ et l’admittance du vide ${Y_{0}}$ sont égales à $1/{\mu_{0}}{c}^{2}$, ${\mu_{0}}{c}$, et $1/{\mu_{0}}{c}$ respectivement, les valeurs de $\varepsilon_{0}$, ${Z_{0}}$ et ${Y_{0}}$ doivent désormais être déterminées de façon expérimentale et ont la même incertitude-type relative que $\mu_{0}$ puisque la valeur de $c$ est connue avec exactitude. Le produit ${\varepsilon_{0}} {\mu_{0}} = 1/{c}^{2}$ et le quotient ${{Z_{0}}}/{\mu_{0}} = {c}$ restent exacts. Au moment de l’adoption de l’actuelle définition de l’ampère, $\mu_{0}$ était égale à ${4\pi \times 10^{-7}\ \rm{H}/\rm{m}}$ avec une incertitude-type relative de ${2.3 \times 10^{-10}}$. @fr

candela1979note1
type: DefinitionNote
has note index: 1
has note text: No notes

candela2018note1
type: DefinitionNote
has note index: 1
has note text: This definition implies the exact relation ${{K_{\rm{cd}}}} = {{683}}\ {{\rm{cd}}\:{\rm{sr}}\:{\rm{kg}}^{-1}\:{\rm{m}}^{-2}\:{\rm{s}}^{3}}$ for monochromatic radiation of frequency ${\nu} = {540 \times 10^{12}}\ {{\rm{Hz}}}$. Inverting this relation gives an exact expression for the candela in terms of the defining constants ${K_{\rm{cd}}}$, ${h}$ and $\Delta\nu_{\rm{Cs}}$: $$1\;{\rm{cd}} = \left(\frac{{K_{\rm{cd}}}}{{683}}\right)\ {\rm{kg}}\ {\rm{m}}^2\ {\rm{s}}^{-3}\ {\rm{sr}}^{-1}$$ which is equal to $$1\;{\rm{cd}} = \frac{1}{(6.626\:070\:15 \times 10^{-34})\:({9\:192\:631\:770})^{2}\:{683}} (\Delta\nu_{\rm{Cs}})^{2}\:{h}\:{K_{\rm{cd}}} \approx 2.614\:8305 \times 10^{10} (\Delta\nu_{\rm{Cs}})^{2}\:{h}\:{K_{\rm{cd}}}$$.
has note text: Cette définition implique la relation exacte ${{K_{\rm{cd}}}} = {{683}}\ {{\rm{cd}}\:{\rm{sr}}\:{\rm{kg}}^{-1}\:{\rm{m}}^{-2}\:{\rm{s}}^{3}}$ pour le rayonnement monochromatique de fréquence ${\nu} = {540 \times 10^{12}}\ {{\rm{Hz}}}$. En inversant cette relation, la candela est exprimée en fonction des constantes ${K_{\rm{cd}}}$, ${h}$ et $\Delta\nu_{\rm{Cs}}$ : $$1\;{\rm{cd}} = \left(\frac{{K_{\rm{cd}}}}{{683}}\right)\ {\rm{kg}}\ {\rm{m}}^2\ {\rm{s}}^{-3}\ {\rm{sr}}^{-1}$$ relation identique à $$1\;{\rm{cd}} = \frac{1}{(6.626\:070\:15 \times 10^{-34})\:({9\:192\:631\:770})^{2}\:{683}} (\Delta\nu_{\rm{Cs}})^{2}\:{h}\:{K_{\rm{cd}}} \approx 2.614\:8305 \times 10^{10} (\Delta\nu_{\rm{Cs}})^{2}\:{h}\:{K_{\rm{cd}}}$$. @fr

candela2018note2
type: DefinitionNote
has note index: 2
has note text: The effect of this definition is that one candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency ${540 \times 10^{12}}\ {{\rm{Hz}}}$ and has a radiant intensity in that direction of ${1/{{683}}}\ {\rm{W}\ \rm{sr}^{-1}}$ The definition of the steradian is given below Table 4.
has note text: Il résulte de cette définition que la candela est l’intensité lumineuse, dans une direction donnée, d’une source qui émet un rayonnement monochromatique de fréquence ${540 \times 10^{12}}\ {{\rm{Hz}}}$ et dont l’intensité énergétique dans cette direction est ${1/{{683}}}\ {\rm{W}\ \rm{sr}^{-1}}$. @fr

kelvin1967note1
type: DefinitionNote
has note index: 1
has note text: The 13th CGPM (1967, Resolution 3) also decided that the unit kelvin and its symbol $\rm{K}$ should be used to express an interval or a difference of temperature.
has note text: La 13ᵉ CGPM (1967, Résolution 3) décida aussi que l'unité kelvin et son symbole $\rm{K}$ sont utilisés pour exprimer un intervalle ou une différence de température. @fr

kelvin1967note2
type: DefinitionNote
has note index: 2
has note text: The 23rd CGPM (2007, Resolution 10) noted that this definition refers to water having the isotopic composition defined by the following amount-of-substance ratios: ${0.000\:155\:76}$ mole of ${^{2}\rm{H}}$ per mole of ${^{1}\rm{H}}$, ${0.000\:379\:9}$ mole of ${^{17}\rm{O}}$ per mole of ${^{16}\rm{O}}$ and ${0.002\:005\:2}$ mole of ${^{18}\rm{O}}$ per mole of ${^{16}\rm{O}}$.
has note text: La 23ᵉ CGPM (2007, Résolution 10) a noté que cette définition se réfère à l'eau de composition isotopique définie par les rapports de quantité de matière suivants: ${0.000\:155\:76}$ mole de ${^{2}\rm{H}}$ par mole de ${^{1}\rm{H}}$, ${0.000\:379\:9}$ mole de ${^{17}\rm{O}}$ par mole de ${^{16}\rm{O}}$ et ${0.002\:005\:2}$ mole de ${^{18}\rm{O}}$ par mole de ${^{16}\rm{O}}$. @fr

kelvin1967note3
type: DefinitionNote
has note index: 3
has note text: In addition to the thermodynamic temperature (symbol $T$), expressed in kelvins, use is also made of Celsius temperature (symbol $t$) defined by the equation where ${T_{0}}$ = 273.15 K by definition. To express celsius temperature, the unit "degree Celsius" which is equal to the unit "kelvin" is used; in this case, "degree Celsius" is a special name used in place of "kelvin". An interval or difference of Celsius temperature can however, be expressed in kelvin as well as in degrees Celsius.
has note text: En dehors de la température thermodynamique (symbole $T$), exprimée en kelvins, on utilise aussi la température Célsius (symbole $t$) définie par l'équation où ${T_{0}}$ = 273.15 K par définition. Pour exprimer la température, on utilise l'unité « degré Célsius » qui est égale à l'unitié « kelvin » ; « degré Célsius » est un nom spécial employé dans ce cas au lieu de « kelvin ». Un intervalle ou une différence de température Célsius peuvent toutefois s'exprimer aussi bien en kelvins qu'en degrés Célsius. @fr

kelvin2018note1
type: DefinitionNote
has note index: 1
has note text: This definition implies the exact relation ${{k}} = {1.380\:649 \times 10^{-23}}\ {{\rm{kg}}\ {\rm{m}}^{2}\ {\rm{s}}^{-2}\ {\rm{K}}^{-1}}$. Inverting this relation gives an exact expression for the kelvin in terms of the defining constants ${k}$, ${h}$ and $\Delta\nu_{\rm{Cs}}$: $$1\;{\rm{K}} = \left(\frac{1.380\:649 \times 10^{-23}}{{k}}\right)\ {{\rm{kg}} \: {\rm{m}}^{2}\:{\rm{s}}^{-2}}$$ which is equal to $$1\;{\rm{K}} = \frac{1.380\:649 \times 10^{-23}}{(6.626\:070\:15 \times 10^{-34})({9\:192\:631\:770})}\frac{\Delta\nu_{\rm{Cs}}\;{h}}{{k}} \approx 2.266\:6653 \frac{\Delta\nu_{\rm{Cs}}\;{h}}{{k}}$$.
has note text: Cette définition implique la relation exacte ${{k}} = {1.380\:649 \times 10^{-23}}\ {{\rm{kg}}\ {\rm{m}}^{2}\ {\rm{s}}^{-2}\ {\rm{K}}^{-1}}$. En inversant cette relation, le kelvin est exprimé en fonction des constantes ${k}$, ${h}$ et $\Delta\nu_{\rm{Cs}}$ : $$1\;{\rm{K}} = \left(\frac{1.380\:649 \times 10^{-23}}{{k}}\right)\ {{\rm{kg}} \: {\rm{m}}^{2}\:{\rm{s}}^{-2}}$$ relation identique à $$1\;{\rm{K}} = \frac{1.380\:649 \times 10^{-23}}{(6.626\:070\:15 \times 10^{-34})({9\:192\:631\:770})}\frac{\Delta\nu_{\rm{Cs}}\;{h}}{{k}} \approx 2.266\:6653 \frac{\Delta\nu_{\rm{Cs}}\;{h}}{{k}}$$. @fr

kelvin2018note2
type: DefinitionNote
has note index: 2
has note text: The effect of this definition is that one kelvin is equal to the change of thermodynamic temperature that results in a change of thermal energy ${{k}}{{T}}$ by ${1.380\:649 \times 10^{-23}}\ {\rm{J}}$.
has note text: Il résulte de cette définition qu’un kelvin est égal au changement de la température thermodynamique résultant d’un changement de l’énergie thermique ${{k}}{{T}}$ de ${1.380\:649 \times 10^{-23}}\ {\rm{J}}$. @fr

kelvin2018note3
type: DefinitionNote
has note index: 3
has note text: The previous definition of the kelvin set the temperature of the triple point of water, ${T_{\rm{TPW}}}$, to be exactly $273.16$ $\rm{K}$. Due to the fact that the present definition of the kelvin fixes the numerical value of ${k}$ instead of ${T_{\rm{TPW}}}$, the latter must now be determined experimentally. At the time of adopting the present definition ${T_{\rm{TPW}}}$ was equal to $273.16$ $\rm{K}$ with a relative standard uncertainty of $3.7 \times 10^{-7}$ based on measurements of ${k}$ made prior to the redefinition.
has note text: La précédente définition du kelvin établissait la température du point triple de l’eau ${T_{\rm{TPW}}}$ comme étant exactement égale à $273.16$ $\rm{K}$. Étant donné que l’actuelle définition du kelvin fixe la valeur numérique de ${k}$ et non plus celle de ${T_{\rm{TPW}}}$, cette dernière doit désormais être déterminée de façon expérimentale. Au moment de l’adoption de l’actuelle définition du kelvin, ${T_{\rm{TPW}}}$ était égale à $273.16$ $\rm{K}$ avec une incertitude-type relative de $3.7 \times 10^{-7}$ déterminée à partir des mesures de ${k}$ réalisées avant la redéfinition.. @fr

kelvin2018note4
type: DefinitionNote
has note index: 4
has note text: As a result of the way temperature scales used to be defined, it remains common practice to express a thermodynamic temperature, symbol ${T}$, in terms of its difference from the reference temperature ${{T_{0}}} = {273.15}\ {\rm{K}}$, close to the ice point. This difference is called the Celsius temperature, symbol ${t}$, which is defined by the quantity equation $${{t}} = {{T}} - {{T_{0}}}$$.
has note text: En raison de la manière dont les échelles de température étaient habituellement définies, il est resté d’usage courant d’exprimer la température thermodynamique, symbole ${T}$, en fonction de sa différence par rapport à la température de référence ${{T_{0}}} = {273.15}\ {\rm{K}}$ proche du point de congélation de l’eau. Cette différence de température est appelée température Celsius, symbole ${t}$ ; elle est définie par l’équation aux grandeurs : $${{t}} = {{T}} - {{T_{0}}}$$. @fr

kelvin2018note5
type: DefinitionNote
has note index: 5
has note text: The unit of Celsius temperature is the degree Celsius, symbol $\rm{{^\circ}{C}}$, which is by definition equal in magnitude to the unit kelvin. A difference or interval of temperature may be expressed in kelvins or in degrees Celsius, the numerical value of the temperature difference being the same in either case. However, the numerical value of a Celsius temperature expressed in degrees Celsius is related to the numerical value of the thermodynamic temperature expressed in kelvin by the relation $${{t}}/{\rm{{^\circ}{C}}} = {{T}}/{\rm{K}} - {273.15}$$.
has note text: L’unité de température Celsius est le degré Celsius, symbole $\rm{{^\circ}{C}}$, qui par définition est égal en amplitude à l’unité « kelvin ». Une différence ou un intervalle de température peut s’exprimer aussi bien en kelvins qu’en degrés Celsius, la valeur numérique de la différence de température étant la même dans les deux cas. La valeur numérique de la température Celsius exprimée en degrés Celsius est liée à la valeur numérique de la température thermodynamique exprimée en kelvins par la relation : $${{t}}/{\rm{{^\circ}{C}}} = {{T}}/{\rm{K}} - {273.15}$$. @fr

kelvin2018note6
type: DefinitionNote
has note index: 6
has note text: The kelvin and the degree Celsius are also units of the International Temperature Scale of 1990 (ITS-90) adopted by the CIPM in 1989 in Recommendation 5 (CI-1989, PV, 57, 115). Note that the ITS-90 defines two quantities ${T_{90}}$ and ${t_{90}}$ which are close approximations to the corresponding thermodynamic temperatures ${T}$ and ${t}$.
has note text: Le kelvin et le degré Celsius sont aussi les unités de l’Échelle internationale de température de 1990 (EIT-90) adoptée par le CIPM en 1989 dans sa Recommandation 5 (CI-1989, PV, 57, 26). Il est à noter que l’EIT-90 définit les deux grandeurs ${T_{90}}$ et ${t_{90}}$ qui sont de très bonnes approximations des températures thermodynamiques correspondantes ${T}$ et ${t}$. @fr

kelvin2018note7
type: DefinitionNote
has note index: 7
has note text: Note that with the present definition, primary realizations of the kelvin can, in principle, be established at any point of the temperature scale.
has note text: Il est également à noter que l’actuelle définition de l’unité de température thermodynamique permet d’établir, en principe, des réalisations primaires du kelvin à tout point de l’échelle de température. @fr

kilogram1901note1
type: DefinitionNote
has note index: 1
has note text: This international prototype, made of platinum-iridium, is kept at the BIPM under conditions specified by the 1st CGPM in 1889.
has note text: Ce prototype international en platine iridié est conservé au Bureau International dans des conditions qui ont été fixées par la CGPM en 1889. @fr

kilogram2018note1
type: DefinitionNote
has note index: 1
has note text: This definition implies the exact relation ${{h}} = {6.626\:070\:15 \times 10^{-34}}\ {{\rm{kg}}\ {\rm{m}}^{2}\ {\rm{s}}^{-1}}$. Inverting this relation gives an exact expression for the kilogram in terms of the three defining constants ${h}$, $\Delta\nu_{\rm{Cs}}$ and $c$: $$1\;{\rm{kg}} = \left(\frac{{h}}{6.626\:070\:15 \times 10^{-34}}\right)\ {{\rm{m}}^{-2}\ {\rm{s}}}$$ which is equal to $$1\;{\rm{kg}} = \frac{(299\:792\:458)^{2}}{(6.626\:070\:15 \times 10^{-34})({9\:192\:631\:770})} \frac{{h}\,\Delta\nu_{\rm{Cs}}}{c^{2}} \approx 1.475\:5214 \times 10^{40} \frac{{h}\,\Delta\nu_{\rm{Cs}}}{c^{2}}$$.
has note text: Cette définition implique la relation exacte ${{h}} = {6.626\:070\:15 \times 10^{-34}}\ {{\rm{kg}}\ {\rm{m}}^{2}\ {\rm{s}}^{-1}}$. En inversant cette relation, le kilogramme est exprimé en fonction des trois constantes ${h}$, $\Delta\nu_{\rm{Cs}}$ et $c$ : $$1\;{\rm{kg}} = \left(\frac{{h}}{6.626\:070\:15 \times 10^{-34}}\right)\ {{\rm{m}}^{-2}\ {\rm{s}}}$$ relation identique à $$1\;{\rm{kg}} = \frac{(299\:792\:458)^{2}}{(6.626\:070\:15 \times 10^{-34})({9\:192\:631\:770})} \frac{{h}\,\Delta\nu_{\rm{Cs}}}{c^{2}} \approx 1.475\:5214 \times 10^{40} \frac{{h}\,\Delta\nu_{\rm{Cs}}}{c^{2}}$$. @fr

kilogram2018note2
type: DefinitionNote
has note index: 2
has note text: The effect of this definition is to define the unit ${\rm{kg}}\ {\rm{m}}^{2}\ {{\rm{s}}^{-1}}$ (the unit of both the physical quantities action and angular momentum). Together with the definitions of the second and the metre this leads to a definition of the unit of mass expressed in terms of the Planck constant ${h}$.
has note text: Cette définition permet de définir l’unité ${\rm{kg}}\ {\rm{m}}^{2}\ {{\rm{s}}^{-1}}$ (l’unité des grandeurs physiques « action » et « moment cinétique »). Ainsi associée aux définitions de la seconde et du mètre, l’unité de masse est exprimée en fonction de la constante de Planck ${h}$. @fr

kilogram2018note3
type: DefinitionNote
has note index: 3
has note text: The previous definition of the kilogram fixed the value of the mass of the international prototype of the kilogram, ${m(\mathcal{K})}$, to be equal to one kilogram exactly and the value of the Planck constant ${h}$ had to be determined by experiment. The present definition fixes the numerical value of ${h}$ exactly and the mass of the prototype has now to be determined by experiment.
has note text: La précédente définition du kilogramme fixait la valeur de la masse du prototype international du kilogramme, ${m(\mathcal{K})}$, à exactement un kilogramme ; la valeur de la constante de Planck ${h}$ devait donc être déterminée de façon expérimentale. L’actuelle définition du kilogrammme fixe la valeur numérique de ${h}$ de façon exacte et la masse du prototype doit désormais être déterminée de façon expérimentale. @fr

kilogram2018note4
type: DefinitionNote
has note index: 4
has note text: The number chosen for the numerical value of the Planck constant in this definition is such that at the time of its adoption, the kilogram was equal to the mass of the international prototype, ${{m(\mathcal{K})}} = 1\ {\rm{kg}}$, with a relative standard uncertainty of $1 \times 10^{-8}$, which was the standard uncertainty of the combined best estimates of the value of the Planck constant at that time.
has note text: Le nombre choisi pour fixer la valeur numérique de la constante de Planck est tel qu’au moment de l’adoption de cette définition de l’unité de masse, le kilogramme était égal à la masse du prototype international ${{m(\mathcal{K})}} = 1\ {\rm{kg}}$ avec une incertitude-type relative égale à $1 \times 10^{-8}$, soit l’incertitude-type de la combinaison des meilleures estimations de la valeur de la constante de Planck à ce moment-là. @fr

kilogram2018note5
type: DefinitionNote
has note index: 5
has note text: Note that with the present definition, primary realizations can be established, in principle, at any point in the mass scale.
has note text: Il est à noter que cette définition de l’unité de masse permet d’établir, en principe, des réalisations primaires à tout point de l’échelle de masse. @fr

metre1960note1
type: DefinitionNote
has note index: 1
has note text: The old international prototype of the metre which was sanctioned by the 1st CGPM in 1889 is still kept at the BIPM under the conditions specified in 1889.
has note text: L'ancien prototype international du metre, qui fut sanctionné par la 1ʳᵉ CGPM en 1889, est toujours conservé au Bureau International des Poids et Mesures dans les conditions fixées en 1889. @fr

metre1983note1
type: DefinitionNote
has note index: 1
has note text: The old international prototype of the metre which was sanctioned by the 1st CGPM in 1889 is still kept at the BIPM under the conditions specified in 1889.
has note text: L'ancien prototype international du metre, qui fut sanctionné par la 1ʳᵉ CGPM en 1889, est toujours conservé au Bureau International des Poids et Mesures dans les conditions fixées en 1889. @fr

metre2018note1
type: DefinitionNote
has note index: 1
has note text: This definition implies the exact relation ${c} = {299\:792\:458}\ {{\rm{m}}\ {{\rm{s}}^{-1}}}$. Inverting this relation gives an exact expression for the metre in terms of the defining constants $c$ and $\Delta\nu_{\rm{Cs}}$: \[$$1\;{\rm{m}} = (\frac{c}{299\:792\:458})\ {\rm{s}} = \frac{{9\:192\:631\:770}}{299\:792\:458} \frac{c}{\Delta\nu_{\rm{Cs}}} ≈ {{30.663\:319}} \frac{c}{\Delta\nu_{\rm{Cs}}}$$\]
has note text: Cette définition implique la relation exacte ${c} = {299\:792\:458}\ {{\rm{m}}\ {{\rm{s}}^{-1}}}$. En inversant cette relation, le mètre est exprimé en fonction des constantes $c$ et $\Delta\nu_{\rm{Cs}}$ : \[$$1\;{\rm{m}} = (\frac{c}{299\:792\:458})\ {\rm{s}} = \frac{{9\:192\:631\:770}}{299\:792\:458} \frac{c}{\Delta\nu_{\rm{Cs}}} ≈ {{30.663\:319}} \frac{c}{\Delta\nu_{\rm{Cs}}}$$\] @fr

metre2018note2
type: DefinitionNote
has note index: 2
has note text: The effect of this definition is that one metre is the length of the path travelled by light in vacuum during a time interval with duration of ${1/299\:792\:458}$ of a second.
has note text: Il résulte de cette définition que le mètre est la longueur du trajet parcouru dans le vide par la lumière pendant une durée de ${1/299\:792\:458}$ de seconde. @fr

mole1971note1
type: DefinitionNote
has note index: 1
has note text: In the definition of the mole, it is understood that unbound atoms of carbon 12, at rest and in their ground state, are referred to.
has note text: Dans la définition de la mole, il est entendu que l'on se réfère à des atomes de carbone 12 non liés, au repos et dans leur état fondamental. @fr

mole1971note2
type: DefinitionNote
has note index: 2
has note text: Note that this definition specifies at the same time the nature of the quantity whose unit is the mole.
has note text: Cette définition précise en même temps la nature de la grandeur dont la mole est l'unité. @fr

mole2018note1
type: DefinitionNote
has note index: 1
has note text: This definition implies the exact relation ${{N_{\rm{A}}}} = {6.022\:140\:76 \times 10^{23}}\ {{\rm{mol}}^{-1}}$. Inverting this relation gives an exact expression for the mole in terms of the defining constant ${N_{\rm{A}}}$: $$1\;{\rm{mol}} = (\frac{6.022\:140\:76 \times 10^{23}}{{N_{\rm{A}}}})$$.
has note text: Cette définition implique la relation exacte ${{N_{\rm{A}}}} = {6.022\:140\:76 \times 10^{23}}\ {{\rm{mol}}^{-1}}$. En inversant cette relation, on obtient l’expression exacte de la mole en fonction de la constante ${N_{\rm{A}}}$ : $$1\;{\rm{mol}} = (\frac{6.022\:140\:76 \times 10^{23}}{{N_{\rm{A}}}})$$. @fr

mole2018note2
type: DefinitionNote
has note index: 2
has note text: The effect of this definition is that the mole is the amount of substance of a system that contains $6.022\:140\:76 \times 10^{23}$ specified elementary entities.
has note text: Il résulte de cette définition que la mole est la quantité de matière d’un système qui contient $6.022\:140\:76 \times 10^{23}$ entités élémentaires spécifiées. @fr

mole2018note3
type: DefinitionNote
has note index: 3
has note text: The previous definition of the mole fixed the value of the molar mass of carbon 12, ${M(^{12}\rm{C})}$, to be exactly $0.012\ {\rm{kg/mol}}$. According to the present definition ${M(^{12}\rm{C})}$ is no longer known exactly and must be determined experimentally. The value chosen for ${N_{\rm{A}}}$ is such that at the time of adopting the present definition of the mole, ${M(^{12}\rm{C})}$ was equal to $0.012\ {\rm{kg/mol}}$ with a relative standard uncertainty of $4.5 \times 10^{-10}$.
has note text: La précédente définition de la mole fixait la valeur de la masse molaire du carbone 12, ${M(^{12}\rm{C})}$), comme étant exactement égale à $0.012\ {\rm{kg/mol}}$. Selon l’actuelle définition de la mole, ${M(^{12}\rm{C})}$ n’est plus connue avec exactitude et doit être déterminée de façon expérimentale. La valeur choisie pour ${N_{\rm{A}}}$ est telle qu’au moment de l’adoption de la présente définition de la mole, ${M(^{12}\rm{C})}$ était égale à $0.012\ {\rm{kg/mol}}$ avec une incertitude-type relative de $4.5 \times 10^{-10}$. @fr

mole2018note4
type: DefinitionNote
has note index: 4
has note text: The molar mass of any atom or molecule X may still be obtained from its relative atomic mass from the equation $${{M(\rm{X})}} = {{A_{\rm{r}}(\rm{X})}}[{{M(^{12}\rm{C})}}/12] = {{A_{\rm{r}}(\rm{X})}}\,{{M_{\rm{u}}}}$$ and the molar mass of any atom or molecule X is also related to the mass of the elementary entity ${m(\rm{X})}$ by the relation $${{M(\rm{X})}} = {{N_{\rm{A}}}}\,{{m(\rm{X})}} = {{N_{\rm{A}}}}\,{{A_{\rm{r}}(\rm{X})}}\,{{m_{\rm{u}}}}$$.
has note text: La masse molaire d’un atome ou d’une molécule X peut toujours être obtenue à partir de sa masse atomique relative à l’aide de l’équation : $${{M(\rm{X})}} = {{A_{\rm{r}}(\rm{X})}}[{{M(^{12}\rm{C})}}/12] = {{A_{\rm{r}}(\rm{X})}}\,{{M_{\rm{u}}}}$$ et la masse molaire d’un atome ou d’une molécule X est également reliée à la masse d’une entité élémentaire m(X) par la relation : ${m(\rm{X})}$ by the relation $${{M(\rm{X})}} = {{N_{\rm{A}}}}\,{{m(\rm{X})}} = {{N_{\rm{A}}}}\,{{A_{\rm{r}}(\rm{X})}}\,{{m_{\rm{u}}}}$$. @fr

mole2018note5
type: DefinitionNote
has note index: 5
has note text: In these equations ${M_{\rm{u}}}$ is the molar mass constant, equal to ${{M(^{12}\rm{C})}}/12$ and ${m_{\rm{u}}}$ is the unified atomic mass constant, equal to ${m(^{12}{\rm{C}})/12}$. They are related to the Avogadro constant through the relation $${{M_{\rm{u}}}} = {{N_{\rm{A}}}}\,{{m_{\rm{u}}}}$$.
has note text: Dans ces équations, ${M_{\rm{u}}}$ est la constante de masse molaire, égale à ${{M(^{12}\rm{C})}}/12$ et ${m_{\rm{u}}}$ est la constante de masse atomique unifiée, égale à ${m(^{12}{\rm{C}})/12}$. Elles sont liées à la constante d’Avogadro par la relation : $${{M_{\rm{u}}}} = {{N_{\rm{A}}}}\,{{m_{\rm{u}}}}$$. @fr

mole2018note6
type: DefinitionNote
has note index: 6
has note text: In the name "amount of substance", the word "substance" will typically be replaced by words to specify the substance concerned in any particular application, for example "amount of hydrogen chloride", or "amount of benzene". It is important to give a precise definition of the entity involved (as emphasized in the definition of the mole); this should preferably be done by specifying the molecular chemical formula of the material involved. Although the word "amount" has a more general dictionary definition, the abbreviation of the full name "amount of substance" to "amount" may be used for brevity. This also applies to derived quantities such as "amount-of-substance concentration", which may simply be called "amount concentration". In the field of clinical chemistry, the name "amount-of-substance concentration" is generally abbreviated to "substance concentration".
has note text: Dans le terme « quantité de matière », le mot « matière » sera généralement remplacé par d’autres mots précisant la matière en question pour chaque application particulière ; on pourrait par exemple parler de « quantité de chlorure d’hydrogène » ou de « quantité de benzène ». Il est important de définir précisément l’entité en question (comme le souligne la définition de la mole), de préférence en précisant la formule chimique moléculaire du matériau concerné. Bien que le mot « quantité » ait une définition plus générale dans le dictionnaire, cette abréviation du nom complet « quantité de matière » est parfois utilisée par souci de concision. Ceci s’applique aussi aux grandeurs dérivées telles que la concentration de quantité de matière, qui peut simplement être appelée « concentration de quantité ». Dans le domaine de la chimie clinique, le nom « concentration de quantité de matière » est généralement abrégé en « concentration de matière ». @fr

second1967note1
type: DefinitionNote
has note index: 1
has note text: No notes

second2018note1
type: DefinitionNote
has note index: 1
has note text: This definition implies the exact relation ${\Delta\nu_{\rm{Cs}}} = {{9\:192\:631\:770}}\ {{\rm{Hz}}}$. Inverting this relation gives an expression for the unit second in terms of the defining constant $\Delta\nu_{\rm{Cs}}$: $$1\;{{\rm{Hz}}} = \frac{\Delta\nu_{\rm{Cs}}}{{9\:192\:631\:770}}\ \rm{or}\ 1\ \rm{s} = \frac{{9\:192\:631\:770}}{\Delta\nu_{\rm{Cs}}}$$
has note text: Cette définition implique la relation exacte ${\Delta\nu_{\rm{Cs}}} = {{9\:192\:631\:770}}\ {{\rm{Hz}}}$. En inversant cette relation, la seconde est exprimée en fonction de la constante $\Delta\nu_{\rm{Cs}}$ : $$1\;{{\rm{Hz}}} = \frac{\Delta\nu_{\rm{Cs}}}{{9\:192\:631\:770}}\ \rm{or}\ 1\ \rm{s} = \frac{{9\:192\:631\:770}}{\Delta\nu_{\rm{Cs}}}$$ @fr

second2018note2
type: DefinitionNote
has note index: 2
has note text: The effect of this definition is that the second is equal to the duration of ${9\:192\:631\:770}$ periods of the radiation corresponding to the transition between the two hyperfine levels of the unperturbed ground state of the ${^{133}\rm{Cs}}$ atom.
has note text: Il résulte de cette définition que la seconde est égale à la durée de ${9\:192\:631\:770}$ périodes de la radiation correspondant à la transition entre les deux niveaux hyperfins de l’état fondamental de l’atome de césium 133 non perturbé. @fr

second2018note3
type: DefinitionNote
has note index: 3
has note text: The reference to an unperturbed atom is intended to make it clear that the definition of the SI second is based on an isolated caesium atom that is unperturbed by any external field, such as ambient black-body radiation.
has note text: Il est fait référence à un atome non perturbé afin d’indiquer clairement que la définition de la seconde du SI se fonde sur un atome de césium isolé qui n’est pas perturbé par un champ externe quel qu’il soit, tel que la radiation d’un corps noir à température ambiante. @fr

second2018note4
type: DefinitionNote
has note index: 4
has note text: The second, so defined, is the unit of proper time in the sense of the general theory of relativity. To allow the provision of a coordinated time scale, the signals of different primary clocks in different locations are combined, which have to be corrected for relativistic caesium frequency shifts.
has note text: La seconde ainsi définie est l’unité de temps propre, au sens de la théorie générale de la relativité. Pour établir une échelle de temps coordonné, les signaux de différentes horloges primaires dans le monde sont combinés, puis des corrections sont appliquées pour tenir compte du décalage relativiste de fréquence entre les étalons à césium. @fr

second2018note5
type: DefinitionNote
has note index: 5
has note text: The CIPM has adopted various secondary representations of the second, based on a selected number of spectral lines of atoms, ions or molecules. The unperturbed frequencies of these lines can be determined with a relative uncertainty not lower than that of the realization of the second based on the ${^{133}\rm{Cs}}$ hyperfine transition frequency, but some can be reproduced with superior stability.
has note text: Le CIPM a adopté différentes représentations secondaires de la seconde fondées sur un nombre choisi de raies spectrales d’atomes, ions ou molécules. Les fréquences non perturbées de ces raies peuvent être déterminées avec une incertitude relative qui n’est pas inférieure à celle de la réalisation de la seconde fondée sur la transition hyperfine de l’atome de ${^{133}\rm{Cs}}$ mais certaines peuvent être reproduites avec une meilleure stabilité. @fr

units 20260303103151Z.ttl generation
type: Activity
started at time: 2026-03-03T10:31:51+00:00
was associated with: cuq tbox.py
was associated with: units abox.py

coulomb
type: SISpecialNamedUnit
has defining resolution: CGPM9-Res7
has symbol: C
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitProduct
  has left unit term: ampere
  has right unit term: second
is unit of qty kind: ELCH
prefix restriction: false

gram
type: MeasurementUnit
preferred label: gramme @fr
has symbol: g
is unit of qty kind: MASS

kelvin
type: SIBaseUnit
has definition: kelvin1967
has definition: kelvin2018
has symbol: K
has unit type as string: SI base unit
has unit type as string: Unité SI de base @fr
is unit of qty kind: TEMT

lumen
type: SISpecialNamedUnit
has defining resolution: CGPM11-Res12
has symbol: lm
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitProduct
  has left unit term: candela
  has right unit term: steradian
in other SI units: UnitProduct
  has left unit term: candela
  has right unit term: steradian
is unit of qty kind: LUFL
prefix restriction: false

mole
type: SIBaseUnit
has definition: mole1971
has definition: mole2018
has symbol: mol
has unit type as string: SI base unit
has unit type as string: Unité SI de base @fr
is unit of qty kind: AMSU

watt
type: SISpecialNamedUnit
has defining resolution: CGPM11-Res12
has symbol: W
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitProduct
  has left unit term: kilogram
  has right unit term: UnitProduct
    has left unit term: UnitPower
      has numeric exponent: 2
      has unit base: metre
    has right unit term: UnitPower
      has numeric exponent: -3
      has unit base: second
in other SI units: UnitProduct
  has left unit term: joule
  has right unit term: UnitPower
    has numeric exponent: -1
    has unit base: second
is unit of qty kind: POWR
prefix restriction: false

ampere1948
type: Definition
preferred label: ampère1948 @fr
has defining resolution: CGPM9-Res2
has defining text: 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 metre apart in vacuum, would produce between these conductors a force equal to ${2 \times 10^{-7}}$ newton per metre of length.
has defining text: L’ampère est l’intensité d’un courant constant qui, maintenu dans deux conducteurs parallèles, rectilignes, de longueur infinie, de section circulaire négligeable et placés à une distance de 1 mètre l’un de l’autre dans le vide, produirait entre ces conducteurs une force égale à ${2 \times 10^{-7}}$ newton par mètre de longueur. @fr
has definition note: ampere1948note1
has end validity: 2019-05-19
has next definition: ampere2018
has start validity: 1948-01-01
has status: superseded
prefix restriction: false

ampere2018
type: Definition
preferred label: ampère2018 @fr
has defining constant: ElementaryCharge
has defining equation: 1\;{\rm{A}} = \left(\frac{{e}}{{1.602\:176\:634 \times 10^{-19}}}\right) {\rm{s}}^{-1}
has defining resolution: CGPM26-Res1
has defining text: The ampere, symbol $\rm{A}$, is the SI unit of electric current. It is defined by taking the fixed numerical value of the elementary charge, ${e}$, to be ${1.602\:176\:634 \times 10^{-19}}$ when expressed in the unit $\rm{C}$, which is equal to ${\rm{A}}\ {\rm{s}}$, where the second is defined in terms of $\Delta\nu_{\rm{Cs}}$.
has defining text: L’ampère, symbole $\rm{A}$, est l’unité de courant électrique du SI. Il est défini en prenant la valeur numérique fixée de la charge élémentaire, ${e}$, égale à ${1.602\:176\:634 \times 10^{-19}}$ lorsqu’elle est exprimée en $\rm{C}$, unité égale à ${\rm{A}}\ {\rm{s}}$, la seconde étant définie en fonction de $\Delta\nu_{\rm{Cs}}$. @fr
has definition note: ampere2018note1
has definition note: ampere2018note2
has definition note: ampere2018note3
has definition note: ampere2018note4
has previous definition: ampere1948
has start validity: 2019-05-20
has status: current
prefix restriction: false

candela1948
type: Definition
has defining constant: LuminousEfficacy
has defining resolution: CIPM41-Res1
has defining text: The value of the new candle is such that the brightness of the full radiator at the temperature of solidification of platinum is 60 new candles per square centimetre.
has defining text: La grandeur de la bougie nouvelle est telle que la brillance du radiateur intégral à la température de solidification du platine soit de 60 bougies nouvelles par centimètre carré. @fr
has end validity: 1967-10-12
has next definition: candela1967
has start validity: 1948-01-01
has status: superseded
prefix restriction: false

candela2018
type: Definition
has defining constant: LuminousEfficacy
has defining equation: 1\;{\rm{cd}} = \left(\frac{{K_{\rm{cd}}}}{683}\right) {\rm{kg}}\;{\rm{m}}^2\;{\rm{s}}^{-3}\;{\rm{sr}}^{-1}
has defining resolution: CGPM26-Res1
has defining text: The candela, symbol $\rm{cd}$, is the SI unit of luminous intensity in a given direction. It is defined by taking the fixed numerical value of the luminous efficacy of monochromatic radiation of frequency ${540 \times 10^{12}}\ {{\rm{Hz}}}$, ${K_{\rm{cd}}}$, to be ${683}$ when expressed in the unit ${\rm{lm}}\ {\rm{W}}^{-1} $, which is equal to ${\rm{cd}}\ {\rm{sr}}\ {\rm{W}}^{-1}$, or ${\rm{cd}}\ {\rm{sr}}\ {\rm{kg}}^{-1}\ {\rm{m}}^{-2}\ {\rm{s}}^{3}$, where the kilogram, metre and second are defined in terms of ${h}$, $c$ and $\Delta\nu_{\rm{Cs}}$.
has defining text: La candela, symbole $\rm{cd}$, est l’unité du SI d’intensité lumineuse dans une direction donnée. Elle est définie en prenant la valeur numérique fixée de l’efficacité lumineuse d’un rayonnement monochromatique de fréquence ${540 \times 10^{12}}\ {{\rm{Hz}}}$, ${K_{\rm{cd}}}$, égale à ${683}$ lorsqu’elle est exprimée en ${\rm{lm}}\ {\rm{W}}^{-1} $, unité égale à ${\rm{cd}}\ {\rm{sr}}\ {\rm{W}}^{-1}$, ou ${\rm{cd}}\ {\rm{sr}}\ {\rm{kg}}^{-1}\ {\rm{m}}^{-2}\ {\rm{s}}^{3}$, le kilogramme, le mètre et la seconde étant définis en fonction de ${h}$, $c$ et $\Delta\nu_{\rm{Cs}}$. @fr
has definition note: candela2018note1
has definition note: candela2018note2
has previous definition: candela1979
has start validity: 2019-05-20
has status: current
prefix restriction: false

kelvin1967
type: Definition
has defining resolution: CGPM13-Res4
has defining text: The kelvin, unit of thermodynamic temperature, is the fraction $1/273.16$ of the thermodynamic temperature of the triple point of water.
has defining text: Le kelvin, unité de température thermodynamique, est la fraction $1/273.16$ de la température thermodynamique du point triple de l'eau. @fr
has definition note: kelvin1967note1
has definition note: kelvin1967note2
has definition note: kelvin1967note3
has end validity: 2019-05-19
has next definition: kelvin2018
has start validity: 1967-10-13
has status: superseded
prefix restriction: false

kelvin2018
type: Definition
has defining constant: BoltzmannConstant
has defining equation: 1\;{\rm{K}} = \left(\frac{1.380\:649 \times 10^{-23}}{{k}}\right) {\rm{kg}}\;{\rm{m}}^2\;{\rm{s}}^{-2}
has defining resolution: CGPM26-Res1
has defining text: The kelvin, symbol $\rm{K}$, is the SI unit of thermodynamic temperature. It is defined by taking the fixed numerical value of the Boltzmann constant, ${k}$, to be $1.380\:649 \times 10^{-23}$ when expressed in the unit ${\rm{J}}\ {\rm{K}}^{-1}$, which is equal to ${\rm{kg}}\ {\rm{m}}^{2}\ {\rm{s}}^{-2}\ {\rm{K}}^{-1}$, where the kilogram, metre and second are defined in terms of ${h}$, $c$ and $\Delta\nu_{\rm{Cs}}$.
has defining text: Le kelvin, symbole $\rm{K}$, est l’unité de température thermodynamique du SI. Il est défini en prenant la valeur numérique fixée de la constante de Boltzmann, ${k}$, égale à $1.380\:649 \times 10^{-23}$ lorsqu’elle est exprimée en ${\rm{J}}\ {\rm{K}}^{-1}$, unité égale à ${\rm{kg}}\ {\rm{m}}^{2}\ {\rm{s}}^{-2}\ {\rm{K}}^{-1}$, le kilogramme, le mètre et la seconde étant définis en fonction de ${h}$, $c$ et $\Delta\nu_{\rm{Cs}}$. @fr
has definition note: kelvin2018note1
has definition note: kelvin2018note2
has definition note: kelvin2018note3
has definition note: kelvin2018note4
has definition note: kelvin2018note5
has definition note: kelvin2018note6
has definition note: kelvin2018note7
has previous definition: kelvin1967
has start validity: 2019-05-20
has status: current
prefix restriction: false

kilogram1901
type: Definition
preferred label: kilogramme1901 @fr
has defining resolution: CGPM3-Res2
has defining text: The kilogram is the unit of mass; it is equal to the mass of the international prototype of the kilogram.
has defining text: Le kilogramme est l’unité de masse ; il est égal à la masse du prototype international du kilogramme. @fr
has definition note: kilogram1901note1
has end validity: 2019-05-19
has next definition: kilogram2018
has start validity: 1901-05-20
has status: superseded
prefix restriction: true

kilogram2018
type: Definition
preferred label: kilogramme2018 @fr
has defining constant: PlanckConstant
has defining equation: 1\;{\rm{kg}} = \left(\frac{{h}}{6.626\:070\:15 \times 10^{-34}}\right) {\rm{m}}^{-2}\;{\rm{s}}
has defining resolution: CGPM26-Res1
has defining text: The kilogram, symbol $\rm{kg}$, is the SI unit of mass. It is defined by taking the fixed numerical value of the Planck constant, ${h}$, to be $6.626\:070\:15 \times 10^{-34}$ when expressed in the unit ${\rm{J}}\ {\rm{s}}$, which is equal to ${\rm{kg}}\ {\rm{m}}^{2}\ {\rm{s}}^{-1}$, where the metre and the second are defined in terms of $c$ and $\Delta\nu_{\rm{Cs}}$.
has defining text: Le kilogramme, symbole $\rm{kg}$, est l’unité de masse du SI. Il est défini en prenant la valeur numérique fixée de la constante de Planck, ${h}$, égale à $6.626\:070\:15 \times 10^{-34}$ lorsqu’elle est exprimée en ${\rm{J}}\ {\rm{s}}$, unité égale à ${\rm{kg}}\ {\rm{m}}^{2}\ {\rm{s}}^{-1}$, le mètre et la seconde étant définis en fonction de $c$ et $\Delta\nu_{\rm{Cs}}$. @fr
has definition note: kilogram2018note1
has definition note: kilogram2018note2
has definition note: kilogram2018note3
has definition note: kilogram2018note4
has definition note: kilogram2018note5
has previous definition: kilogram1901
has start validity: 2019-05-20
has status: current
prefix restriction: true

metre1889
type: Definition
preferred label: mètre1889 @fr
has defining resolution: CGPM1-Res1
has defining text: The CGPM sanctions the Prototype of the metre chosen by the CIPM. This prototype, at the temperature of melting ice, shall henceforth represent the metric unit of length.
has defining text: La CGPM sanctionne le Prototype du mètre choisi par le Comité international. Ce prototype représentera désormais, à la température de la glace fondante, l'unité métrique de longueur. @fr
has end validity: 1927-09-29
has next definition: metre1927
has start validity: 1889-05-20
has status: superseded
prefix restriction: false

metre2018
type: Definition
preferred label: mètre2018 @fr
has defining constant: SpeedOfLight
has defining equation: 1\;{\rm{m}} = \left(\frac{c}{299\:792\:458}\right) {\rm{s}} = \frac{{9\:192\:631\:770}}{299\:792\:458} \frac{c}{\Delta\nu_{\rm{Cs}}} \approx {30.663\:319} \frac{c}{\Delta\nu_{\rm{Cs}}}
has defining resolution: CGPM26-Res1
has defining text: The metre, symbol $\rm{m}$, is the SI unit of length. It is defined by taking the fixed numerical value of the speed of light in vacuum, $c$, to be $299\:792\:458$ when expressed in the unit ${\rm{m}}\ {{\rm{s}}^{-1}}$, where the second is defined in terms of the caesium frequency $\Delta\nu_{\rm{Cs}}$.
has defining text: Le mètre, symbole $\rm{m}$, est l’unité de longueur du SI. Il est défini en prenant la valeur numérique fixée de la vitesse de la lumière dans le vide, $c$, égale à $299\:792\:458$ lorsqu’elle est exprimée en ${\rm{m}}\ {{\rm{s}}^{-1}}$, la seconde étant définie en fonction de $\Delta\nu_{\rm{Cs}}$. @fr
has definition note: metre2018note1
has definition note: metre2018note2
has previous definition: metre1983
has start validity: 2019-05-20
has status: current
prefix restriction: false

mole1971
type: Definition
has defining resolution: CGPM14-Res3
has defining text: 1. 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; its symbol is “mol”. 2. 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.
has defining text: 1. La mole est la quantité de matière d’un système contenant autant d’entités élémentaires qu’il y a d’atomes dans 0,012 kilogramme de carbone 12 ; son symbole est « mol ». 2. Lorsqu’on emploie la mole, les entités élémentaires doivent être spécifiées et peuvent être des atomes, des molécules, des ions, des électrons, d’autres particules ou des groupements spécifiés de telles particules. @fr
has definition note: mole1971note1
has definition note: mole1971note2
has end validity: 2019-05-19
has next definition: mole2018
has start validity: 1971-10-04
has status: superseded
prefix restriction: false

mole2018
type: Definition
has defining constant: AvogadroConstant
has defining equation: 1\;{\rm{mol}} = \left(\frac{6.022\:140\:76 \times 10^{23}}{{N_{\rm{A}}}}\right)
has defining resolution: CGPM26-Res1
has defining text: The mole, symbol $\rm{mol}$, is the SI unit of amount of substance. One mole contains exactly $6.022\:140\:76 \times 10^{23}$ elementary entities. This number is the fixed numerical value of the Avogadro constant, ${N_{\rm{A}}}$, when expressed in the unit ${\rm{mol}}^{-1}$ and is called the Avogadro number. The amount of substance, symbol ${n}$, of a system is a measure of the number of specified elementary entities. An elementary entity may be an atom, a molecule, an ion, an electron, any other particle or specified group of particles.
has defining text: La mole, symbole $\rm{mol}$, est l’unité de quantité de matière du SI. Une mole contient exactement $6.022\:140\:76 \times 10^{23}$ entités élémentaires. Ce nombre, appelé « nombre d’Avogadro », correspond à la valeur numérique fixée de la constante d’Avogadro, ${N_{\rm{A}}}$, lorsqu’elle est exprimée en ${\rm{mol}}^{-1}$. La quantité de matière, symbole ${n}$, d’un système est une représentation du nombre d’entités élémentaires spécifiées. Une entité élémentaire peut être un atome, une molécule, un ion, un électron, ou toute autre particule ou groupement spécifié de particules. @fr
has definition note: mole2018note1
has definition note: mole2018note2
has definition note: mole2018note3
has definition note: mole2018note4
has definition note: mole2018note5
has definition note: mole2018note6
has previous definition: mole1971
has start validity: 2019-05-20
has status: current
prefix restriction: false

second1960
type: Definition
preferred label: seconde1960 @fr
has defining resolution: CGPM11-Res9
has defining text: The second is the fraction $1/31556925.9747$ of the tropical year for 1900 January 0 at 12 hours ephemeris time.
has defining text: La seconde est la fraction $1/31556925.9747$ de l'année tropique pour 1900 janvier 0 à 12 heures de temps des éphémérides. @fr
has end validity: 1967-10-12
has next definition: second1967
has start validity: 1960-10-18
has status: superseded
prefix restriction: false

second2018
type: Definition
preferred label: seconde2018 @fr
has defining constant: HyperfineTransitionFrequencyOfCs-133
has defining equation: 1\;{\rm{Hz}} = \frac{\Delta\nu_{\rm{Cs}}}{{9\:192\:631\:770}} \quad {\rm{or}} \quad 1\;{\rm{s}} = \frac{{9\:192\:631\:770}}{\Delta\nu_{\rm{Cs}}}
has defining resolution: CGPM26-Res1
has defining text: The second, symbol $\rm{s}$, is the SI unit of time. It is defined by taking the fixed numerical value of the caesium frequency, $\Delta\nu_{\rm{Cs}}$, the unperturbed ground-state hyperfine transition frequency of the caesium 133 atom, to be ${9\:192\:631\:770}$ when expressed in the unit ${\rm{Hz}}$, which is equal to ${\rm{s}}^{-1}$.
has defining text: La seconde, symbole $\rm{s}$, est l’unité de temps du SI. Elle est définie en prenant la valeur numérique fixée de la fréquence du césium, $\Delta\nu_{\rm{Cs}}$, la fréquence de la transition hyperfine de l’état fondamental de l’atome de césium 133 non perturbé, égale à ${9\:192\:631\:770}$ lorsqu’elle est exprimée en ${\rm{Hz}}$, unité égale à ${\rm{s}}^{-1}$. @fr
has definition note: second2018note1
has definition note: second2018note2
has definition note: second2018note3
has definition note: second2018note4
has definition note: second2018note5
has previous definition: second1967
has start validity: 2019-05-20
has status: current
prefix restriction: false

newton
type: SISpecialNamedUnit
has defining resolution: CGPM9-Res7
has symbol: N
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitProduct
  has left unit term: kilogram
  has right unit term: UnitProduct
    has left unit term: metre
    has right unit term: UnitPower
      has numeric exponent: -2
      has unit base: second
is unit of qty kind: FORC
prefix restriction: false

weber
type: SISpecialNamedUnit
has defining resolution: CGPM11-Res12
has symbol: Wb
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitProduct
  has left unit term: kilogram
  has right unit term: UnitProduct
    has left unit term: UnitPower
      has numeric exponent: 2
      has unit base: metre
    has right unit term: UnitProduct
      has left unit term: UnitPower
        has numeric exponent: -2
        has unit base: second
      has right unit term: UnitPower
        has numeric exponent: -1
        has unit base: ampere
in other SI units: UnitProduct
  has left unit term: volt
  has right unit term: second
is unit of qty kind: MGFL
prefix restriction: false

candela1967
type: Definition
has defining constant: LuminousEfficacy
has defining resolution: CGPM13-Res5
has defining text: The candela is the luminous intensity, in the perpendicular direction, of a surface of $1/600\,000$ square metre of a black body at the temperature of freezing platinum under a pressure of $101\,325$ newtons per square metre.
has defining text: La candela est l'intensité lumineuse, dans la direction perpendiculaire, d'une surface de $1/600\,000$ mètre carré d'un corps noir à la température de congélation du platine sous la pression de $101\,325$ newtons par mètre carré. @fr
has end validity: 1979-10-10
has next definition: candela1979
has previous definition: candela1948
has start validity: 1967-10-13
has status: superseded
prefix restriction: false

candela1979
type: Definition
has defining constant: LuminousEfficacy
has defining resolution: CGPM16-Res3
has defining text: The candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency $540 \times 10^{12}$ hertz and that has a radiant intensity in that direction of $1/{{683}}$ watt per steradian.
has defining text: La candela est l’intensité lumineuse, dans une direction donnée, d’une source qui émet un rayonnement monochromatique de fréquence $540 \times 10^{12}$ hertz et dont l’intensité énergétique dans cette direction est $1/{{683}}$ watt par stéradian. @fr
has definition note: candela1979note1
has end validity: 2019-05-19
has next definition: candela2018
has previous definition: candela1967
has start validity: 1979-10-11
has status: superseded
prefix restriction: false

metre1927
type: Definition
preferred label: mètre1927 @fr
has defining resolution: CGPM7-Res1
has defining text: The unit of length is the metre, defined by the distance, at 0°, between the axes of the two central lines marked on the bar of platinum-iridium kept at the Bureau International des Poids et Mesures and declared Prototype of the metre by the 1st Conférence Générale des Poids et Mesures, this bar being subject to standard atmospheric pressure and supported on two cylinders of at least one centimetre diameter, symmetrically placed in the same horizontal plane at a distance of $571\ \rm{mm}$ from each other.
has defining text: L'unité de longueur est le mètre, défini par la distance, à ${0{^\circ}}$, des axes des deux traits médians tracés sur la barre de platine iridié déposée au Bureau international des poids et mesures, et déclarée Prototype du mètre par la Première Conférence générale des poids et mesures, cette règle étant soumise à la pression atmosphérique normale et supportée par deux rouleaux d'au moins un centimètre de diamètre, situés symétriquement dans un même plan horizontal et à la distance de $571\ \rm{mm}$ l'un de l'autre. @fr
has end validity: 1960-10-13
has next definition: metre1960
has previous definition: metre1889
has start validity: 1927-09-30
has status: superseded
prefix restriction: false

metre1960
type: Definition
preferred label: mètre1960 @fr
has defining resolution: CGPM11-Res6
has defining text: The metre is the length equal to $1\,650\,763.73$ wavelengths in vacuum of the radiation corresponding to the transition between the levels $2\rm{p}^{10}$ and $5\rm{d}^{5}$ of the krypton 86 atom.
has defining text: Le mètre est la longueur égale à $1\,650\,763.73$ longueurs d'onde dans le vide de la radiation correspondant à la transition entre les niveaux $2\rm{p}^{10}$ et $5\rm{d}^{5}$ de l'atome de krypton 86. @fr
has definition note: metre1960note1
has end validity: 1983-10-16
has next definition: metre1983
has previous definition: metre1927
has start validity: 1960-10-14
has status: superseded
prefix restriction: false

metre1983
type: Definition
preferred label: mètre1983 @fr
has defining constant: SpeedOfLight
has defining resolution: CGPM17-Res1
has defining text: The metre is the length of the path travelled by light in vacuum during a time interval of ${1/299\:792\:458}$ of a second.
has defining text: Le mètre est la longueur du trajet parcouru dans le vide par la lumière pendant une durée de ${1/299\:792\:458}$ de seconde. @fr
has definition note: metre1983note1
has end validity: 2019-05-19
has next definition: metre2018
has previous definition: metre1960
has start validity: 1983-10-17
has status: superseded
prefix restriction: false

second1967
type: Definition
preferred label: seconde1967 @fr
has defining constant: HyperfineTransitionFrequencyOfCs-133
has defining resolution: CGPM13-Res1
has defining text: 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 caesium 133 atom.
has defining text: La seconde est la durée de ${9\:192\:631\:770}$ périodes de la radiation correspondant à la transition entre les deux niveaux hyperfins de l’état fondamental de l’atome de césium 133. @fr
has definition note: second1967note1
has end validity: 2019-05-19
has next definition: second2018
has previous definition: second1960
has start validity: 1967-10-13
has status: superseded
prefix restriction: false

candela
type: SIBaseUnit
has definition: candela1948
has definition: candela1967
has definition: candela1979
has definition: candela2018
has symbol: cd
has unit type as string: SI base unit
has unit type as string: Unité SI de base @fr
is unit of qty kind: LUIN

radian
type: SISpecialNamedUnit
has defining resolution: CGPM11-Res12
has symbol: rad
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitProduct
  has left unit term: metre
  has right unit term: UnitPower
    has numeric exponent: -1
    has unit base: metre
is unit of qty kind: ANGP
prefix restriction: false

steradian
type: SISpecialNamedUnit
preferred label: stéradian @fr
has defining resolution: CGPM11-Res12
has symbol: sr
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitProduct
  has left unit term: UnitPower
    has numeric exponent: 2
    has unit base: metre
  has right unit term: UnitPower
    has numeric exponent: -2
    has unit base: metre
is unit of qty kind: ANGS
prefix restriction: false

joule
type: SISpecialNamedUnit
has defining resolution: CGPM11-Res12
has symbol: J
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitProduct
  has left unit term: kilogram
  has right unit term: UnitProduct
    has left unit term: UnitPower
      has numeric exponent: 2
      has unit base: metre
    has right unit term: UnitPower
      has numeric exponent: -2
      has unit base: second
in other SI units: UnitProduct
  has left unit term: newton
  has right unit term: metre
is unit of qty kind: ENGY
prefix restriction: false

volt
type: SISpecialNamedUnit
has defining resolution: CGPM11-Res12
has symbol: V
has unit type as string: Named SI derived unit
has unit type as string: Unité SI dérivée ayant un nom spécial @fr
in base SI units: UnitProduct
  has left unit term: kilogram
  has right unit term: UnitProduct
    has left unit term: UnitPower
      has numeric exponent: 2
      has unit base: metre
    has right unit term: UnitProduct
      has left unit term: UnitPower
        has numeric exponent: -3
        has unit base: second
      has right unit term: UnitPower
        has numeric exponent: -1
        has unit base: ampere
in other SI units: UnitProduct
  has left unit term: watt
  has right unit term: UnitPower
    has numeric exponent: -1
    has unit base: ampere
is unit of qty kind: ELPD
prefix restriction: false

ampere
type: SIBaseUnit
preferred label: ampère @fr
has definition: ampere1948
has definition: ampere2018
has symbol: A
has unit type as string: SI base unit
has unit type as string: Unité SI de base @fr
is unit of qty kind: ELCU

kilogram
type: PrefixedUnit
type: SIBaseUnit
preferred label: kilogramme @fr
has definition: kilogram1901
has definition: kilogram2018
has non prefixed unit: gram
has prefix: kilo
has symbol: kg
has unit type as string: SI base unit
has unit type as string: Unité SI de base @fr
is unit of qty kind: MASS

second
type: SIBaseUnit
preferred label: seconde @fr
has definition: second1960
has definition: second1967
has definition: second2018
has symbol: s
has unit type as string: SI base unit
has unit type as string: Unité SI de base @fr
is unit of qty kind: TIME

metre
type: SIBaseUnit
preferred label: mètre @fr
has definition: metre1889
has definition: metre1927
has definition: metre1960
has definition: metre1983
has definition: metre2018
has symbol: m
has unit type as string: SI base unit
has unit type as string: Unité SI de base @fr
is unit of qty kind: LENG