

S = rθ Formula and EquationRadian Measure and Arc of a Circle There is a formula that relates the arc length of a circle of radius, r, to the central angle ,θ in radians.
Formula for S =rθThe picture below illustrates the relationship between the radius, and the central angle in radians. The formula is
Demonstration of the Formual s=rθ
The interative demonstration below illustrates the relationship between the central angle of a circle, measured in radians, and the length of the intercepted arc. Just click and drag the points.
What is the value of the arc length s in the circle pictured below?
Use the s=rθ formula S = 3(Π/3) = Π
What is the value of the arc length s in the circle pictured below?
Calculate the measure of the arc length s in the circle pictured below?
Calculate the measure of the arc length s in the circle pictured below?
Further Reading
