Arc Lengths of a Circle

Lesson: Finding an Arc Length on a Circle

By Steven Giesting

​Recall from earlier classes that the distance around a circle is called the circumference.

​

We can calculate the circumference in 1 of 2 ways.

​

​

​Today, we want to learn how to determine the length of an arc. Think about it like finding the distance we walk if we don't go all the way around the circle.

ARC LENGTH

Multiple Choice

Calculate the length of the bold arc.

• 49.7 ft

• 15.8 ft

• 24.9 ft

• 3.14 ft

Multiple Choice

Calculate the length of the bold arc.

• 5040 cm

• 43 cm

• 44 cm

• 14 cm

Multiple Choice

Find the length of the bolded arc to the nearest hundredth.

• 11.54

• 12.11

• 11.21

• 9.89

Fill in the Blanks

Find the arc length of AB.

Fill in the Blanks

Find the arc length of PQ.