The radius of a sphere is equal to the radius of the base as well as the height of a right circular cylinder. What is the ratio of surface area of sphere and curved surface area of cylinder respectively?
Answer & explanation
Correct answer: option 1
We know that,
The radius of the sphere = r
The radius of cylinder = R
Height of cylinder = h
Surface area of sphere = 4π r2
The curved surface area of the cylinder = 2πRh
According to the question,
r = R = h
Curved surface area of cylinder = 2 × π × R × h = 2 × π × r × r = 2π r2
The surface area of the sphere: Curved surface area of cylinder = 4π r2 : 2π r2 = 2: 1