- cm
6.
7.
- or
- or
- mm
- inches
- inch feet or equivalent
- inches
Circumferenceand Arc Length
LearningObjectives
- Understandthe basicidea of a limit.
- Calculatethe circumferenceof a circle.
- Calculatethe lengthof an arc of a circle.
Introduction
In this lesson,we extendour knowledgeof perimeterto the perimeter—orcircumference—ofa circle.We’ll
use the idea of a limit to derivea well-knownformulafor the circumference.We’ll also use commonsense
to calculatethe lengthof part of a circle,knownas an arc.
The Partsof a Circle
Acircleis the set of all pointsin a planethat are a givendistancefrom anotherpointcalledthe center. Flat
roundthings,like a bicycletire, a plate,or a coin,remindus of a circle.