Question

arc cd is $\frac{1}{4}$ of the circumference of a circle. what is the radian measure of the central angle?$\bigcirc$ $\frac{pi}{4}$ radians$\bigcirc$ $\frac{pi}{2}$ radians$\bigcirc$ $2pi$ radians$\bigcirc$ $4pi$ radians

Explanation:

Step1: Recall full circle radians

A full circle has a central angle of $2\pi$ radians.

Step2: Calculate 1/4 of full angle

Multiply the full circle angle by $\frac{1}{4}$:
$\frac{1}{4} \times 2\pi = \frac{\pi}{2}$

Answer:

$\frac{\pi}{2}$ radians