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Broytingar

|'''1960'''||<!--{{val|1650763.73}} [[wavelength]]s in a [[vacuum]] of the [[electromagnetic radiation|radiation]] corresponding to the transition between the 2p{{sup|10}} and 5d{{sup|5}} quantum levels of the [[krypton]]-86 [[atom]]. -->
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|'''1983'''||longdinLongdin, sum ljós ferðast í tómrúminum í {{sfrac|299&#8239;792&#8239;458}} sekund.
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|style="background:#F5F5F5" rowspan=3|'''[[kilogramm]]'''
|'''1793'''||<!-- The '''grave''' was defined as being the weight [mass] of one cubic decimetre of pure water at its freezing point.<sup>FG</sup> -->
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|'''1889'''||massinMassin á ''millumtjóða kilogrammprototypuni'' (ein [[platin]]-[[iridium]]-sylindari hjá [[BIPM]], [[Sèvres]], París).
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|'''2019'''||1 kg er Plancks konstantur býttur við 6,626&#8239;070&#8239;15&#8239;×&#8239;10<sup>−34</sup> m<sup>2</sup>/s
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|style="background:#F5F5F5" rowspan=3|'''[[sekund]]'''
|'''1946'''||style="line-height:11pt"|støddin á einum jøvnum streymi, sum, tá hann rennur í tveimum parallellum, óendaliga longum og óendaliga tunnum leiðarum í vakum og 1 m millum teirra, ger, at leiðararnir ávirka hvønn annan við 2&#8239;×&#8239;10<sup>−7</sup> N/m.
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|'''2019'''||style="line-height:11pt"|1 ampere er elementarløðinginElementarløðingin býtt við 1,602&#8239;176&#8239;634&#8239;×&#8239;10<sup>−19</sup> s.
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|style="background:#F5F5F5" rowspan=4|'''[[kelvin]]'''
|'''1900'''||<!-- The [[Molecular mass|molecular weight]] of a substance in mass grams.<sup>ICAW</sup> -->
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|'''1967'''||einEin mongd líka stór sum talið av atomum í 12&nbsp;g av <sup>12</sup>C.
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|'''2019'''||6,022&#8239;140&#8239;76&#8239;×&#8239;10<sup>23</sup> elementareindir.
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|style="background:#F5F5F5" rowspan=2|'''[[candela]]'''
|'''1946'''||luminansurinLuminansurin frá einum likami við smeltitemperaturin hjá platin er 60 cd/cm<sup>2</sup>.
<!-- 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. -->
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|'''1979'''||style="line-height:5pt"|ljósstyrkinLjósstyrkin í ein rætning frá eini ljóskeldu, sum sendir út monokromatiskt ljós við frekvensinum 540&nbsp;THz og strálingsstyrkini {{sfrac|683}}&nbsp;W/sr í henda rætningin.<br>&nbsp;
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rættingar