Find the length s of the arc of a circle of radius 85 centimeters subtended by the central angle 36°.
Solution:-
A central angle is an angle whose vertex is at the center of a circle. The rays of a central angle subtend (intersect) an arc on the circle. We have the following theorem.
Arc Length
For a circle of radius r, a central angle θ radians subtends an arc whose length s is
s = r θ
Convert angle in degrees to radians.
1° = 
radian
36° = 36 * radian
radian
s(arc length) = rθ
= 85 centimeters*
=17π centimeters
53.407 centimeters