Arc of a sector th 180pr th 180 p r. Sector area is found A 1 2 thr2 A 1 2 th r 2 where th th is in radian. The arc length of a Sector or Segment is.
Example 1 Find the arc length and area of a sector of a circle of radius 6 6 cm and the centre angle 2p 5 2 p 5.
Th180 pr The arc length L of a sector of angle th in a circle of radius r is given by. The arc length formula is used to find the length of an arc of a circle. Calculate the area of a sector. Where th equals the measure of the central angle that intercepts the arc and r equals the length of the radius.