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articles:nist_traceability [2019/05/25 12:20] – [What are SI Units?] rrandall | articles:nist_traceability [2019/05/25 12:39] – [What are SI Units?] rrandall | ||
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The SI Units are defined in the [[https:// | The SI Units are defined in the [[https:// | ||
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- | SI Units are also explained on the NIST web site at: https:// | ||
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- | Alternatively, | ||
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- | * The kilogram – will be defined in terms of the Planck constant (h) | ||
- | * The ampere – will be defined in terms of the elementary charge (e) | ||
- | * The kelvin – will be defined in terms of the Boltzmann constant (k) | ||
- | * The mole – will be defined in terms of the Avogadro constant (NA) | ||
Because SI units are derived from intrinsic (i.e., invariant) constants of nature, " | Because SI units are derived from intrinsic (i.e., invariant) constants of nature, " | ||
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b) a documented unbroken chain of calibrations going back to stated and appropriate references (appropriate references include national or international standards, and __intrinsic standards__);// | b) a documented unbroken chain of calibrations going back to stated and appropriate references (appropriate references include national or international standards, and __intrinsic standards__);// | ||
</ | </ | ||
+ | |||
+ | SI Units are also explained on the NIST web site at: https:// | ||
+ | |||
+ | * The kilogram – will be defined in terms of the Planck constant (h) | ||
+ | * The ampere – will be defined in terms of the elementary charge (e) | ||
+ | * The kelvin – will be defined in terms of the Boltzmann constant (k) | ||
+ | * The mole – will be defined in terms of the Avogadro constant (NA) | ||
+ | |||
+ | While these units remain the same //size//, the change simply //defines// them more precisely. And their usage in normal, every day life will appear as unchanged. However, the new units will impact a small number of high level calibrations. | ||
+ | |||
===== What are " | ===== What are " | ||