An arc is a portion of the circumference of a circle. For instance, when you cut up a circular pizza through its centre severally, its circumference gets divided into arcs.
Formula to calculate the length of an arc.
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Where; AB – is the arc length.
θ – is the angle subtended by radius MA and radius MB.
r – is the radius also labelled as MA and MB.
π – is a constant estimated to be 3.142.
Example:
Calculate the length of an arc with radius 10cm and the angle ssubtended by the radius is 50 degrees.
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Therefore, the length of the arc is 8.728 cm.