How do you find the length of an arc of a circle with a radius of 18cm if the arc subtends a central angle of 2(pi) / 3?

1 Answer
Jul 28, 2015

The arc has length 12πcm. (About 37.7cm.)

Explanation:

The radian measure of an angle, θ can be defined by:

Let θ be a central angle in a circle of radius r. Let s be the length of the arc cut off by θ. Then the radian measure os θ is given by:

θ=sr

Thus if we are given radius and the central angle in radians, we can find the arc length using:

s=rθ

In this case::

s=18cm2π3

=62πcm

=12πcm