Arcs and Chords

 A Chord is a line segment that joins ANY two points on a circle

In other words, a chord is basically any line segment starting one one side of a circle, like point A in the picture on the left, and ending on another side of the circle, like point B. Points A and B are the endpoints of chord AB. A chord of a circle is a line segment whose two endpoints lie on the circle. The diameter, passing through the circles centre, is the longest chord in a circle. A tangent to a circle is a straight line that touches the circle at a single point. A secant is an extended chord: a straight line cutting the circle at two points.

• Chords are equidistant from the center if and only if their lengths are equal.
• A chord's perpendicular bisector passes through the centre.
• If the line extensions (secant lines) of chords AB and CD intersect at a point P, then their lengths satisfy AP*PB = CP*PD

The area that a circular chord "cuts off" is called a circular segment. A chord of a circle is a line segment that connects one point on the edge of the circle with another point on the circle.

(The diameter is a chord------ its just the longest chord)

An arc of a circle is any connected part of the circles circumference. A sector is a region bounded by two radii and an arc lying between the radii, and a segment is a region bounded by a chord and an arc lying between the chords endpoints.

Minor Arc - If the measure of a central angle APB is less than 180°, then A and B and the points of circle P in the interior of angle APB form a minor arc of the circle.

Major Arc - The points A and B and the points of circle P in the exterior of angle APB for a major arc. OR if the measure of a central angle APB is greater than 180⁰, and less then 360°, then A and B and the points of circle P in the interior of ∠APB form a major arc of the circle.

An arc is a closed segment of a differentiable curve in the twodimensional plane; for example, a circular arc is a segment of the circumference of a circle. If the arc segment occupies a great circle (or great ellipse), it is considered a great-arc segment. An arc is a portion of the circumference of a circle. if the measure of a central angle APB is less than 180°, then A and B and the points of circle P in the interior of angle APB form a minor arc of the circle. and less then 360°, then A and B and the points of circle P in the interior of ∠APB form a major arc of the circle.