SI plane angle measure. Symbol: rad. It is the
angle of a circle subtended by an arc equal in length to the circle's
radius. Another definition is: the plane angle between two radii of a
circle which cut off on the circumference an arc equal in length to the
radius. Radian = m/m = 1.
SUMO / UNITS-OF-MEASURE
Related WordNet synsets
- radian, rad
- the unit of plane angle adopted under the System International d'Unites; equal to the angle at the center of a circle subtended by an arc equal in length to the radius (approximately 57.295 degrees)
If number is an instance of real number, then "number angular degree(s)" is equal to ""number*"pi/"" radian(s)".
(instance ?NUMBER RealNumber)
(MeasureFn ?NUMBER AngularDegree)
(DivisionFn Pi 180))