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International Prototype of the Kilogram

The International Prototype of the Kilogram (referred to by metrologists as the IPK or Le Grand K; sometimes called the ur-kilogram, or urkilogram, particularly by German-language authors writing in English:30: 64 ) is an object whose mass was used to define the kilogram from 1889, when it replaced the Kilogramme des Archives, until 2019, when it was…

Measurement, Art & Standards

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Overview

Creation

Copies of the IPK

Stability of the IPK

Dependency of the SI on the IPK

Advanced semantic analysis

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Map overview Semantic statistics

International Prototype of the Kilogram

Nodes139
Edges138
Triples4
Avg. degree1.99
Density0.014388
Components1

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Important terminology

ipk mass kilogram si prototypes μg copies defined national stored used metre standards one units 10 bipm second verification replicas

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
thisinstance ofQuite unlike transient variations0.80text
the US's check standardinstance ofQuite unlike transient variations0.80text
K4instance ofQuite unlike transient variations0.80text
has persistently declined in mass relative to the IPKinstance ofQuite unlike transient variations0.80text

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