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angle of arc/ angle of circle (360°) = length of the arc/ total circumference (2 pi* radius)
so you just have to find r then so:
angle of arc/ angle of circle (360°) *2pi = length of the arc/ radius
radius= ength of the arc/ angle of arc/ angle of circle (360°) *2pi
not that hard ;)
Arc length = (x/360)*2 pi r
NB In radial terms 360 = 2 pi
Hence
Arc length = (x/2 pi) *2 pi r
Cancel down by '2 pi'
Hence
Arc length = x*r
Hence
r = Arc length / x
Where 'x' is the angular value in radians.
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