Page 165 - New Medley 5 Semester 2

  Arc: It is a part of boundary of the circle. In the given figure, APC is an
arc of the circle.

  Semicircle: The diameter of a circle divides it into two equal halves.

Each of the halves is called a semicircle.

 In the given figure, the region enclosed by AOBRA is a semicircle.

  Segment: The chord of a circle divides it into two parts. Each part is

called a segment.
 In the given figure, the region APCA is a minor segment. The remaining

part of the circle is the major segment. Major segment is greater than

a semicircle while minor segment is smaller than it.

  Sector: The region bounded by two radii and an arc is called sector
of the circle.

In the given figure, the region OBQCO is a sector. It is a minor

sector as corresponding arc BQC is a minor arc, i.e., less than half of
circumference.

Interior and Exterior of a Circle

Consider the given circle and its surroundings. Here, OA is its radius and
O is its centre.

Here, some points are marked. If we join the points P, R and S with the

centre O, we find that
OP < OA That means, P lies in the interior
S
of the circle. R

OR = OA That means, R lies on the circle.

OS > OA That means, S lies on the exterior
Q
of the circle.
A
Thus, the region enclosed by circumference of O

the circle is called its interior. And the region
outside the boundary of a circle is called its P

exterior. In the given figure, the shaded region

shows the interior of the circle. T

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