Question

A piece of wire 20 cm long is bent into the from of an arc of a circle, subtending an angle of `60^(@)` at its centre. Find the radius of the circle.

Answer 1

Length of arc of circle = 20 cm
Here, central angle `theta = 60^(@)`
`:.` Length of arc = `(theta)/(360^(@))xx2pir`
`rArr 20=(60^(@))/(360^(@))xx2pirrArr(20xx6)/(2pi) =r`
`r = (60)/(pi)cm`
Hence, the radius of circle is `(60)/(pi) cm`.