Perimeter of sector: Learn how to calculate the

Learn how to calculate the perimeter of a sector by adding the arc length and the two radii. See examples, worksheets and related lessons on circles, sectors and arcs. What is Sector of a Circle? A sector is a segment of a circle that includes an arc and the two radii that connect the arc's endpoints to the circle's centre. It represents a fraction of the circle, defined by the arc—part of the circle's perimeter—and the radii at the arc's ends. The perimeter of a circle sector is the combined length of two radii and the arc that forms the sector. The formula to calculate the perimeter of a sector is derived below. The region bounded by two radii of a circle and the arc intercepted by them is called a sector of the circle. A sector is measured by the angle which its arc subtends at the centre of the circle.