591:
577:
153:
in 1935 without specifying which electromagnetic unit would be the fourth base unit. In 1939, the
Consultative Committee for Electricity (CCE) recommended the adoption of Giorgi's proposal, using the ampere as the fourth base unit. This was subsequently approved by the CGPM in 1954.
43:(MKS) as base units. Distances are described in terms of metres, mass in terms of kilograms and time in seconds. Derived units are defined using the appropriate combinations, such as velocity in metres per second. Some units have their own names, such as the
929:(1935), "Adoption of the Metre–Kilogram-Mass–Second (M.K.S.) Absolute System of Practical Units by the International Electrotechnical Commission (I.E.C.), Bruxelles, June, 1935",
1213:
145:. The CGS and MKS systems were both widely used in the 20th century, with the MKS system being primarily used in practical areas, such as commerce and engineering. The
141:, such as the volt, ohm or ampere, be used to create a coherent system using practical units. This system was strongly promoted by electrical engineer
83:
837:
1013:
78:. A coherent system of units is one where all units are directly derived from a set of base units, without the need of any conversion factors. The
1258:
627:
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1208:
1780:
1527:
1252:
621:
123:
1805:
146:
692:
Cammack, Richard; Atwood, Teresa; Campbell, Peter; Parish, Howard; Smith, Anthony; Vella, Frank; Stirling, John, eds. (2006-01-01).
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55:
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1831:
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1426:
1327:
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58:, was originally created as a formalization of the MKS system. The SI has been redefined several times since then and is now
1841:
1411:
1349:
1006:
1775:
1562:
122:
of 1875, work started on international prototypes for the kilogram and the metre, which were formally sanctioned by the
1815:
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59:
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137:(AEI) that the MKS system, extended with a fourth unit to be taken from the practical units of
126:(CGPM) in 1889, thus formalizing the MKS system by using the kilogram and metre as base units.
1022:
521:
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703:
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8:
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142:
16:
Physical system of measurement that uses the metre, kilogram, and second as base units
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892:
707:
672:
62:, but still closely approximates the original MKS units for most practical purposes.
172:
The MKS units with the ampere as a fourth base unit is sometimes referred to as the
1342:
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884:
699:
664:
138:
119:
98:
and second. These units were inconvenient for electromagnetic applications, since
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Proceedings of the
National Academy of Sciences of the United States of America
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47:
unit of force which is the combination kilogram metre per second squared.
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1091:
991:
628:
Vacuum permeability § Systems of units and historical origin of value of
189:
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87:
71:
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234:
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811:. National Institute of Standards and Technology. December 12, 2017
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102:
units derived from these did not correspond to the commonly used
1537:
303:
177:
111:
40:
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313:
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244:
32:
82:
are an example of a non-coherent set of units. In 1874, the
691:
411:
336:
107:
95:
457:
115:
875:
Brainerd, John G. (1970). "Some
Unanswered Questions".
695:
Oxford
Dictionary of Biochemistry and Molecular Biology
572:
663:(6 ed.). Oxford University Press. 2009-01-01.
639:
Vacuum permittivity § Rationalization of units
31:, is a physical system of measurement based on the
925:
868:
84:British Association for the Advancement of Science
843:. Bureau International des Poids et Mesures. 2006
1880:
60:based entirely on fundamental physical constants
863:Atti dell' Associazione Elettrotecnica Italiana
70:By the mid-19th century, there was a demand by
1007:
762:. University of North Carolina at Chapel Hill
167:rationalization of electromagnetic equations
733:Classical Mechanics: An Introductory Course
726:
1021:
1014:
1000:
192:was added as a seventh base unit in 1971.
124:General Conference on Weights and Measures
960:
950:
803:
801:
799:
356:Named MKSA electromagnetic derived units
176:. This system was extended by adding the
147:International Electrotechnical Commission
874:
838:"The International System of Units (SI)"
782:"What makes a system of units coherent?"
753:
751:
749:
350:
184:as base units in 1960, thus forming the
832:
830:
828:
826:
698:(2 ed.). Oxford University Press.
149:(IEC) adopted Giorgi's proposal as the
21:metre, kilogram, second system of units
1881:
796:
757:
605:Centimetre–gram–second system of units
995:
746:
823:
704:10.1093/acref/9780198529170.001.0001
669:10.1093/acref/9780199233991.001.0001
135:Associazione elettrotecnica italiana
727:Fitzpatrick, Richard (2006-02-02).
212:Named MKS mechanical derived units
206:
13:
1044:International System of Units (SI)
622:Metre–tonne–second system of units
163:rationalized metre–kilogram–second
14:
1905:
980:
90:, a coherent system based on the
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195:
919:
735:. University of Texas at Austin
855:
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56:Système international d'unités
1:
1054:US customary units (USCS/USC)
987:Description of the MKS system
644:
186:International System of Units
80:United States customary units
52:International System of Units
23:, also known more briefly as
758:Rowlet, Russ (May 2, 2018).
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809:"Brief history of the SI"
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611:Foot–pound–second system
76:coherent system of units
1146:Quantum chromodynamical
660:A Dictionary of Physics
151:M.K.S. System of Giorgi
1259:centimetre–gram–second
1023:Systems of measurement
952:10.1073/pnas.21.10.579
877:Technology and Culture
86:(BAAS) introduced the
54:(SI), from the French
1781:Biblical and Talmudic
1247:metre–kilogram–second
883:(4). JSTOR: 601–603.
522:magnetic flux density
351:Electromagnetic units
760:"Units: CGS and MKS"
617:List of metric units
471:electric conductance
425:electric capacitance
165:) combines MKS with
943:1935PNAS...21..579K
545:electric inductance
448:electric resistance
357:
213:
1253:metre–tonne–second
1049:UK imperial system
927:Arthur E. Kennelly
784:. Sizes, Inc. 2003
355:
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143:George A. Campbell
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1670:Costa Rican
1634:Seychellois
1543:Singaporean
1338:Traditional
1193:Metrication
1131:Geometrised
1087:Avoirdupois
729:"mks units"
174:MKSA system
50:The modern
1883:Categories
1756:Venezuelan
1741:Paraguayan
1695:Nicaraguan
1573:Vietnamese
1548:Sri Lankan
1533:Philippine
1493:Indonesian
1417:Portuguese
1311:Winchester
1214:Comparison
1164:Background
1102:Electrical
739:2024-03-04
645:References
92:centimetre
88:CGS system
72:scientists
29:MKS system
1751:Uruguayan
1736:Colombian
1726:Brazilian
1716:Argentine
1654:Tanzanian
1624:Mauritian
1594:Ethiopian
1558:Taiwanese
1528:Pakistani
1508:Mongolian
1483:Cambodian
1402:Norwegian
1372:Icelandic
1367:Hungarian
1360:Byzantine
1316:Exchequer
1064:Hong Kong
913:112215565
897:0040-165X
562:kgâ‹…mâ‹…sâ‹…A
516:kgâ‹…mâ‹…sâ‹…A
488:kgâ‹…mâ‹…sâ‹…A
465:kgâ‹…mâ‹…sâ‹…A
442:kgâ‹…mâ‹…sâ‹…A
419:kgâ‹…mâ‹…sâ‹…A
361:Quantity
235:frequency
217:Quantity
129:In 1901,
25:MKS units
1837:Obsolete
1832:Humorous
1786:Egyptian
1746:Peruvian
1721:Bolivian
1685:Honduran
1649:Tunisian
1629:Moroccan
1619:Malagasy
1604:Eritrean
1599:Egyptian
1589:Algerian
1518:Nepalese
1498:Japanese
1432:Scottish
1422:Romanian
1323:Estonian
1233:Historic
1209:Overview
1178:Overview
1075:Specific
971:16577693
569:See also
281:pressure
161:system (
37:kilogram
1868:Modulor
1842:Unusual
1811:Persian
1769:Ancient
1731:Chilean
1690:Mexican
1680:Haitian
1609:Guinean
1513:Myanmar
1452:Swedish
1447:Spanish
1437:Serbian
1427:Russian
1407:Ottoman
1397:Maltese
1387:Latvian
1382:Italian
1328:Finnish
1306:English
1286:Cypriot
1281:Cornish
1188:History
1183:Outline
1118:Natural
1059:Chinese
1037:General
1030:Current
962:1076662
939:Bibcode
905:3102695
539:kgâ‹…sâ‹…A
481:siemens
402:voltage
389:coulomb
344:kgâ‹…mâ‹…s
321:kgâ‹…mâ‹…s
298:kgâ‹…mâ‹…s
275:kgâ‹…mâ‹…s
182:candela
66:History
27:or the
1863:N-body
1801:Indian
1776:Arabic
1639:Somali
1614:Libyan
1582:Africa
1553:Syrian
1503:Korean
1488:Indian
1478:Afghan
1442:Slovak
1412:Polish
1350:German
1333:French
1296:Danish
1274:Europe
1240:Metric
1171:Metric
1151:Stoney
1141:Planck
1126:Atomic
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847:May 4,
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304:energy
291:pascal
268:newton
188:. The
178:kelvin
112:ampere
45:newton
41:second
39:, and
1851:Other
1816:Roman
1796:Hindu
1791:Greek
1675:Cuban
1563:Tatar
1523:Omani
1462:Welsh
1457:Swiss
1377:Irish
1355:Greek
1301:Dutch
1291:Czech
1261:(CGS)
1255:(MTS)
1249:(MKS)
1221:(FPS)
1202:UK/US
909:S2CID
901:JSTOR
841:(PDF)
624:(MTS)
613:(FPS)
607:(CGS)
555:henry
532:tesla
509:weber
435:farad
367:Unit
327:power
314:joule
258:force
245:hertz
223:Unit
33:metre
1568:Thai
1538:Pegu
1471:Asia
1109:(US)
1092:Troy
967:PMID
893:ISSN
849:2021
817:2021
790:2021
768:2021
708:ISBN
673:ISBN
412:volt
396:sâ‹…A
337:watt
190:mole
180:and
159:rmks
157:The
114:and
108:volt
96:gram
19:The
957:PMC
947:doi
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499:Φ
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416:V
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341:W
332:P
318:J
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286:p
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