Dictionary
Coherent system of units
A system of units in which every derived unit is coherent — the SI as used with its base and coherent derived units. VIM (JCGM…
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75 results for “System of units”
Dictionary
System of units
A set of base and derived units, with their multiples and submultiples, defined under given rules for a given system of quantities. VIM (JCGM…
Dictionary
Off-system measurement unit
A unit that does not belong to the system of units in use — the day, the electronvolt, and the nautical mile relative to the…
Dictionary
International System of Units (SI)
The system of units based on the ISQ, with unit names, symbols, prefixes, and rules for their use, adopted by the CGPM. Since the…
Documents
SP 330 — International System of Units
NIST Special Publication 330 The International System of Units (SI) 2019 EDITION SP 330 David B. Newell and Eite Tiesinga, Editors This publication is…
The practical style guide for using SI units, symbols, and conversion factors in US practice. Freely available; the full text is readable in the…
The US edition of the SI Brochure reflecting the 2019 redefinition in which all seven base units derive from fixed defining constants. Freely available…
The defining document of the SI: the seven defining constants, base and derived units, prefixes and usage rules. Ninth edition with rolling updates (v4…
Dictionary
System of quantities
A set of quantities together with the non-contradictory equations relating them — the framework a system of units is built on. VIM (JCGM 200…
Documents
SP 811 — Guide for the Use of SI Units
Guide for the Use of the International System of Units (SI) 76 This page intentionally left blank.