Arc of a sector

Using the same reasoning about radians we can also work out the length of any arc on a circle.

Example

Work out the length of the arc AB

Work out the length of this circles circumference using radians

Circumference $=2pir$

Therefore Circumference $=2pi times12$ $cm$

$=24pi$ $cm$

Logic progresses as follows:

$24pi=100%$ of the circumference

$360^@=24pi$ $cm$

$60^@=x$ $cm$

Answer: The arc is $x=4pi$ $cm$ long