What is Sector and Segment of a Circle?

Sector of a circle is the region inside the circle made by two radii and the arc of the circle connecting the two radii of the circle. The segment of a circle is the region inside the circle made by the chord and the arc connecting the two endpoints of the chord.

Definition of Sector

The region formed by the two radii of the circle and the arc between them is called the sector of a circle. The sector of a circle can be of two types:

• Major Sector
• Minor Sector

The diagram below represents the sector of a circle.

Definition of Segment

The region formed by the chord of circle and the arc between the two points of the chord is called as segment of a circle. The segment of circle can be of two types:

• Major Segment
• Minor Segment

The below diagram represents the segment of the circle.

Areas of sector and segment of a circle with radius r and subtends an angle θ (in radians) are given by (1/2)×θr² and (1/2)×r²(θ -sinθ) respectively. The area of the sector and the area of the segment of the circle are easily calculated using the above formula.

In this article, we will explore the areas of sector and segment in detail and also learn the basics of sector and segment of a circle.