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abstraction > mathematical concept > unit > angle unit > radian
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radian
(rad)
subjectfact 
radianhas symbol radhas source: Jerrard, H.G., McNeill, D.B. 1992 Dictionary of Scientific Units, Chapman and Hall, 2001-09-27 09:32:47.0
has proposer James Thomsonhas source: Jerrard, H.G., McNeill, D.B. 1992 Dictionary of Scientific Units, Chapman and Hall, 2001-09-27 09:32:47.0
has equivalent 57.29578°has source: Jerrard, H.G., McNeill, D.B. 1992 Dictionary of Scientific Units, Chapman and Hall, 2001-09-27 09:32:47.0
has base unit m·m-1 = 12001-09-27 09:32:47.0
has proposal date 1873has source: Jerrard, H.G., McNeill, D.B. 1992 Dictionary of Scientific Units, Chapman and Hall, 2001-09-27 09:32:47.0
has definition Unit of angular measure equal to the angle subtended at the centre of a circle by an arc the length of which is equal to the radius. There are 2π radians in a circle. The angle π/4 is called an octant and a thousandth of a radian is sometimes called a mil, which is equal to 3 minutes 26.5 seconds of arc.has source: Jerrard, H.G., McNeill, D.B. 1992 Dictionary of Scientific Units, Chapman and Hall, 2001-09-27 09:32:47.0
has definition A measure of angular distance; 2π radians equals 360 degrees.has source: Silk, J. 1990 The Big Bang, W. H. Publishers, New York, 2001-09-27 09:32:47.0
is an instance of angle unit2001-09-27 09:32:47.0
is an instance of named derived SI unit2001-09-27 09:32:47.0
angle unitis a unit of angle2001-09-27 09:32:47.0
unithas historical origin2001-09-27 09:32:42.0
represents2001-09-27 09:32:42.0
derived SI unithas unit defined in terms of derived SI unit via a system of quantity equations2001-09-27 09:32:56.0
SI unitis an acronym for Syteme Internationale2001-09-27 09:32:55.0