7. Arc – Sector - Segment
• A part of the circumference of a circle is
called a circular arc.
• The plane surface that is enclosed between
two radii and the circular arc of a circle is
called a sector.
• Each part of a circle which is divided by a
chord is called a segment.
8. Parts of the Circle
Arc Sector Segment Arc-Sector-Segment
9. Central Angle
A central angle is the angle that forms
when two radii meet at the center of a
circle.
Remember that a vertex is the
point where two lines meet to form an
angle. A central angle's vertex will
always be the center point of a circle.
10. Central Angle
Th e central angle of a circle is
360°.
If a circle is divided into ‘n’ equ
al sectors, the central angle of
each of the sectors is 𝜃0
=
360
𝑛