Radian facts for kids
A radian is a unit of measuring angles. It is shown by the symbol "rad" or, less often, c (for circular measure). The radian was once an SI supplementary unit, but was changed to a derived unit in 1995.
Most people who do mathematics or physics use radians, rather than degrees, because some kinds of calculations, mostly in trigonometry and calculus, are simpler when using radians rather than degrees. Thus, most calculations related to angular frequency (such as angular velocity) use radians per second.
1 radian is equal to about 57.3°. There are 2π radians (about 6.28 radians) in a full circle. The formula for turning radians to degrees and vice versa is:
we can also say that:
Radian Facts for Kids. Kiddle Encyclopedia.