This is an authorized Web site of Jehovahâs Witnesses. It is a research tool for publications in various languages produced by Jehovahâs Witnesses. Watchtower ONLINE LIBRARY
There are a number of meanings for the word arc in mathematics. In general, an arc is any smooth curve joining two points. The length of an arc is known as its arc length. In a graph, a graph arc is an ordered pair of adjacent vertices. In particular, an arc is any portion (other than the entire curve) of the circumference of a circle. An arc corresponding to the central angle is denoted . Similarly, the size of the central angle subtended by this arc (i.e., the measure of the arc) is sometimes (e.g., Rhoad et al.
An arc is a portion of the circumference of a circle. In the figure above, the arc is the blue part of the circle. Strictly speaking, an arc could be a portion of some other curved shape, such as an ellipse, but it almost always refers to a circle. To avoid all possible mistake, it is sometimes called a circular arc. A straight line is drawn between the end points of the arc would be a chord of the circle. If the arc length is exactly half the circle, this called a semicircular arc. See Semicircle definition.