Chapter C, Problem 5E

To determine

To find: The length of the circular arc.

Answer to Problem 5E

The length of the circular arc is   $3\pi$ cm.

Explanation of Solution

The length of the circular disc is $a=r\theta$ where the radius $r$ and $\theta$ is the central angle.

Here, it is given that $\theta =\frac{\pi }{12}$ rad and $r=36$ cm.

Substitute the value $\theta =\frac{\pi }{12}$ rad and $r=36$ cm in the formula $a=r\theta$.

$\begin{array}{c}a=r\theta \\ =\frac{\pi }{12}\left(36\right)\\ =3\pi \end{array}$

Thus, the length of the circular arc is $3\pi$ cm.