A radian is the angle subtended at the center of a circle when the arc length equals the radius.
1 radian ≈ 57.3° | π radians = 180° | 2π radians = 360°
Angle: 0.00 rad (0.00°)
Arc Length: 0.00 r
Radius: 1.00 r
Watch the green arc grow along the circle. At what angle does the arc length exactly equal the radius? How many radii fit around the full circumference?
A radian is the angle subtended at the center of a circle when the arc length equals the radius.
1 radian ≈ 57.3° | π radians = 180° | 2π radians = 360°
Angle: 0.00 rad (0.00°)
Arc Length: 0.00 r
Radius: 1.00 r