Question

The surface area of a sphere is same as the curved surface area of a right circular cylinder whose height and diameter are 12 cm each. The radius of the sphere is

Options

• 3 cm

• 4 cm

• 6 cm

• 12 cm

Answer 1

Let r be the radius of sphere

But,

Surface area of sphere = C.S.A. of cylinder

`4pir^2 = 2pirh`

   `4r^2 = 2 xx 6 xx 12 `

     `r^2 = (2 xx 6 xx 12)/4`

        `r = 6cm`