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ABSTRACT
In this article, the definition and use of units and more specifically, the International System of Units is discussed. Established in 1960, it has subsequently been revised́ several times to meet user requirements and advances in science and technology. Since its establishment, the SI units have been defined in terms of a set of seven base units. All other units, called derived units, are formed from power products of the base units.
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Thibaut FOURCADE: Engineer - This article is the updated version of article TBA100 entitled "Units", written in 2004.
INTRODUCTION
The International System of Units (SI) was defined and established in 1960 at the 11th meeting of the General Conference on Weights and Measures (CGPM). This system of units, legally used in France, has undergone several revisions. The latest, and probably the most important, was approved in October 2018 at the 26th meeting of the CGPM.
The definitions of the units in this system are based on a set of seven physical constants, expressed in SI, from which we can deduce all the units in the system.
The seven base units are the ampere, candela, kelvin, kilogram, meter, mole and second. There are also derived units, defined as products of powers of the base units.
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KEYWORDS
System | Unit | International | Mesure
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Units
International System (SI)
Regulations
Laws
Law of July 4, 1837, amended by the law of July 15, 1944, relating to the metric system and the verification of weights and measures.
Law of April 2, 1919 on units of measurement, amended by the law of January 14, 1948.
Decrees
Decree no. 61-501 of May 3, 1961 (OJ of May 20, 1961 corrected August 11, 1961) and amended by...
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