Are you an EPFL student looking for a semester project?
Work with us on data science and visualisation projects, and deploy your project as an app on top of Graph Search.
Concept
Unit of length
Summary
A unit of length refers to any arbitrarily chosen and accepted reference standard for measurement of length. The most common units in modern use are the metric units, used in every country globally. In the United States the U.S. customary units are also in use. British Imperial units are still used for some purposes in the United Kingdom and some other countries. The metric system is sub-divided into SI and non-SI units.
Metric system
International System of Units
Orders of magnitude (length)
The base unit in the International System of Units (SI) is the metre, defined as "the length of the path travelled by light in vacuum during a time interval of seconds." It is approximately equal to 1.0936yards. Other SI units are derived from the metre by adding prefixes, as in millimetre or kilometre, thus producing systematic decimal multiples and submultiples of the base unit that span many orders of magnitude. For example, a kilometre is 1000meters.
In the centimetre–gram–second system of units, the basic unit of length is the centimetre, or of a metre.
Other non-SI units are derived from decimal multiples of the metre.
Imperial unitsUnited States customary units and English units#length
The basic unit of length in the imperial and U.S. customary systems is the yard, defined as exactly 0.9144m by international treaty in 1959.
Common imperial units and U.S. customary units of length include:
thou or mil ( of an inch)
inch (25.4mm)
foot (12 inches, 0.3048 m)
yard (3 feet, 0.9144 m)
(terrestrial) mile (5280 feet, 1609.344 m)
(land) league
In addition, the following are used by sailors:
fathom (for depth; only in non-metric countries) (2 yards = 1.8288 m)
nautical mile (one minute of arc of latitude = 1852m)
Aviators use feet for altitude worldwide (except in Russia and China) and nautical miles for distance.
Surveyors in the United States continue to use:
chain (22 yards, or 20.1168m)
rod (also called pole or perch) (quarter of a chain, 5 yards, or 5.
Official source
About this result
This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.