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radian

File:Circle_radians.gif · Wikimedia Commons · See Wikimedia Commons

EntityQ33680· pop 89· linked from 612 articles

Also known as rad

The radian, denoted by the symbol rad, is the unit of angle in the International System of Units (SI) and is the standard unit of angular measure used in many areas of mathematics. It is defined such that one radian is the angle subtended at the center of a plane circle by an arc that is equal in length to the radius. The unit is defined in the SI as the coherent unit for plane angle, as well as for phase angle. Angles without explicitly specified units are generally assumed to be measured in radians, especially in mathematical writing.

AI overview

A radian is the standard unit for measuring angles in mathematics and the International System of Units, defined as the angle created at the center of a circle when an arc length equals the radius of that circle. Radians matter because they're the default unit for angles in mathematical work, making calculations and formulas simpler and more consistent across science and engineering.

AI-generated from the Wikipedia summary — may contain errors.

Key facts

Unit.standard
SI
Unit.name
Radian
Unit.image
Circle radians.gif
Unit.caption
An arc of a circle with the same length as the radius of that circle subtends an angle of 1 radian. The circumference subtends an angle of 2 radians.
Unit.quantity
angle
Unit.symbol
rad
Unit.units1
milliradians
Unit.inunits1
1000 mrad
Unit.units2
turns
Unit.inunits2
turn ≈ 0.159154 turn
Unit.units3
degrees
Unit.inunits3
° ≈ 57.295779513°
Unit.units4
gradians
Unit.inunits4
 grad ≈ 63.661977g

via Wikipedia infobox

Wikidata facts

Image
Radian - en.svg
Show 5 more facts
conversion to SI unit
1
Commons category
Radian
Unicode character
unit symbol
рад
Wikidata SPARQL query equivalent
wd:Q33680 p:P2370/psn:P2370 [wikibase:quantityAmount ?source; wikibase:quantityUnit ?base]. ?item p:P2370/psn:P2370 [wikibase:quantityAmount ?target; wikibase:quantityUnit ?base]. BIND(?source / ?target as ?value)
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Article

17 sections
Contents
  • Definition
  • Unit symbol
  • Dimensional analysis
  • Conversions
  • Between degrees
  • Between gradians
  • Usage
  • Mathematics
  • Physics
  • Prefixes and variants
  • History
  • Pre-20th century
  • As an SI unit
  • See also
  • Notes
  • References
  • External links

The radian, denoted by the symbol rad, is the unit of angle in the International System of Units (SI) and is the standard unit of angular measure used in many areas of mathematics. It is defined such that one radian is the angle subtended at the center of a plane circle by an arc that is equal in length to the radius. The unit is defined in the SI as the coherent unit for plane angle, as well as for phase angle. Angles without explicitly specified units are generally assumed to be measured in radians, especially in mathematical writing.

== Definition ==

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