Areas of Sector and Segment of a Circle
Areas of Sector and Segment of a Circle: Overview
This topic discusses finding the formulae for areas of the sector of an angle and length of an arc of a sector of the angle of a circle using some general terms as given in the figure. Students will find some examples illustrating these formulae.
Important Questions on Areas of Sector and Segment of a Circle
If the area of the shaded region in the given figure is and if and is the centre of the circle. Find . [write the answer up to two decimal places and use ].

A brooch is made with silver wire in the form of a circle with diameter The wire is also used in making diameters which divide the circle into equal sectors as shown in the below figure. Find the area of each sector of the brooch.

A horse is tied to a peg at one corner of a square shaped grass field of side by means of a long as given in figure. Find the increase in the grazing area if the rope were long instead of (use )

In a circle of radius an arc subtends an angle of at the centre.
Find the area of the segment formed by the corresponding chord

In a circle of radius an arc subtends an angle of at the centre.
Find area of the sector formed by the arc

A chord of a circle of radius subtends a right angle at the centre. Find the area of the corresponding major sector.
(Use

Area of a sector of angle in degrees of a circle with radius is

A round table cover has six equal designs as shown in figure. If the radius of the cover is find the cost of making the designs at the rate of per (Use )

To warn ships for underwater rocks, a lighthouse spreads a red coloured light over a sector of angle to a distance of . Find the area of the sea over which the ships warned (Use ).

A car has two wipers which do not overlap. Each wiper has blade of length sweeping through an angle of . Find the total area cleaned at each sweep of the blades.

An umbrella has ribs which are equally spaced as shown in figure. Assuming umbrella to be a flat circle of radius find the area between the two consecutive ribs of the umbrella.

A brooch is made with silver wire in the form of a circle with diameter The wire is also used in makingdiameters which divide the circle into equal sectors as shown in figure. Find the total length of the silver wire required.

A horse is tied to a peg at one corner of a square shaped grass field of side by means of a long rope (see Fig.. Find the area of that part of the field in which the horse can graze.
(use )

A chord of a circle of radius subtends an angle of at the centre. Find the areas of the corresponding segment of the circle. ( Use and )

A chord of a circle of radius subtends an angle of at the centre. Find the areas of the corresponding minor and major segments of the circle.
(Use and )

In a circle of radius an arc subtends an angle of at the centre. Find the length of the arc?

A chord of a circle of radius subtends a right angle at the centre. Find the area of the corresponding minor segment (use .

The length of the minute hand of a clock is Find the area swept by the minute hand in minutes.

Find the area of a quadrant of circle whose circumference is

Find the area of a sector of a circle with radius if angle of the sector is
