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SAI International School
                                                       CLASS - X

               Mathematics


               CHAPTER-11: Area related of circles-1                          Lesson Notes-1


               SUBTOPIC :  Area Of Sector, Length of an arc.


               Sector- The part of the circular region enclosed by two radii and the corresponding arc
               of the circle, by joining the centre to the endpoints of the arc is called a Sector.



               It is a portion of the circle formed by a portion of the circumference (arc) and radii of
               the circle at both endpoints of the arc. The shape of a sector of a circle can be
               compared with a slice of pizza or a pie.





















               The sector is basically a portion of a circle which could be defined based on these three
               points mentioned below:

                   •  A circular sector is the portion of a disk enclosed by two radii and an arc.


                   •  A sector divides the circle into two regions namely Major and Minor Sector.

                   •  The smaller area is known as the Minor Sector whereas the region having
                       Greater area is known as Major Sector.









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