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Unit

Metre

Also Known As Meter
SI Base Units

The metre is the base unit of length in the International System of Units. Since 2019 it has been defined by fixing the speed of light at exactly 299,792,458 metres per second, so the metre is the distance light travels in a vacuum in 1/299,792,458 of a second, tying length directly to the definition of the second and a fixed constant of nature rather than to any physical object. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/

Facts
Classification
Quantity MeasuredSourced to the subject's own account
Length 1
Unit SystemSourced to the subject's own account
International System of Units (SI) 1
SymbolSourced to the subject's own account
m 1
Connections

Measures Quantity

Length, Concepts

Used In

Physics, Disciplines
Source International System of Units (Wikipedia)
Sources
1. International System of Units (Wikipedia)
Wikipedia
  • Lede
    US English uses the spelling deka-, meter, and liter, and International English uses deca-, metre, and litre.
  • Lede, quantity measured
    The metre is the base unit of length in the International System of Units.
  • Lede, unit system
    The metre is the base unit of length in the International System of Units.
  • Used In: Physics
View the Source
Bureau International des Poids et Mesures (BIPM): The International System of Units (SI), 9th edition
Bureau International des Poids et Mesures (BIPM)In Group: Mechanical Base Units, PDF page 129
Quote, In Group: Mechanical Base Units, PDF page 129
The metre, symbol m, is the SI unit of length.
View the Source
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