Properties of Circles

5.1  Properties of Circles

Radius:   A straight line from the centre of the circle to any point on the circumference.
Sector:   The region enclosed by two radii and an arc.
Segment:   The region enclosed by a chord and an arc.
Arc:   Part of the circumference.
Diameter:   A straight line that touches the circumference through the centre of the circle.
Chord:   A straight line that joins any two points on the circumference.
Circumference:   The perimeter of a circle.
Centre:   A fixed point where all points on the circumference are equidistance from it.