Circular Arc
The next topic in this section is the length of a circular arc. A circular arc is part of a circle.
The arc is said to subtend the central angle.
To find the length of the arc, you can draw the following circle:
Write the following proportion:
Solve for s:
The length of an arc of a circle is therefore defined as , where r is equal to the radius of the circle, and θ is equal to the central angle, in radians. Make sure to change all measures from degrees to radians before using this formula.