The angle of a sector of a circle of radius 8cm is 240°. This sector is bent to form a cone. Find the radius of the base of the cone.
- A.
16/3cm - B.
15/3cm - C.
16/5cm - D.
8/3cm - E.
16/10cm
Correct Answer: Option A
Explanation
L = θ/360 x 2πR = 240/360 x 2 x 22/7 x 8/1 … (1)
This must be equal to the circumference of the circle which is 2πr = 44R/7 …. (2)
equate (1) and (2)
r = 16/3 = 51/3