Question

Find the length of an arc of a circle which subtends an angle of 108° at the centre, if the radius of the circle is 15 cm.

Answer 1

Here, r = 15 cm and

θ = 108° = `(108 xx pi/180)^"c"` 

= `((3pi)/5)^"c"`

Since S = r.θ,

S = `15 xx (3pi)/5`

= 9π cm.