## Parts of a Circle

Labels for the different parts of a circle are given below

 Radius – the radius of a circle is the distance from the centre labelled O to the circumference. The radius is labelled  The circumference of a circle is the perimeter, and is labelled   Diameter – diameter of a circle is the length of a straight line between opposite ends drawn through the centre. The diameter is labelled and is equal to  Tangent – A straight line drawn outside the circle which just touches it. Chord - a line (not through the centre) drawn between any two points on the circumference. Arc – a part of the circumference. The length of an arc is where is the radius and is the angle in radians. Sector - the part of a a circle between two radii and an arc. We can divide a circle into major and minor sectors. The area of a sector is where is the angle in radians. Segment - the part of a a circle between chord and an arc. We can divide a circle into major and minor segments. The area of the minor segment on the right is where is in radians.  