Mensurationhard · Past Paper
Find the surface area of a sphere whose volume is 4.5π cubic cm.
A9π cm²
B4.5π cm²
C12π cm²
D6π cm²
✓ Correct Answer: A — 9π cm²
V = 4/3 πr³ = 4.5π => r³ = 4.5 * 3 / 4 = 13.5/4 = 3.375 => r = 1.5. Area = 4π(1.5)² = 4π * 2.25 = 9π cm².
Share this question
More from Mensuration
- A square is inscribed in an equilateral triangle of side 12 cm. Find the area of the square.
- What is the surface area of a solid composed of a cylinder and a hemisphere attached to one of its circular bases with common radius 'r' and cylinder height 'h'?
- A cone has a volume of 314 cm^3 and a height of 12 cm. Find its base radius (Take π = 3.14).
- A metal pipe has an external diameter of 4 cm and internal diameter of 3 cm. If its length is 20 cm, find the volume of metal used.
- If the base radius of a cone is 3 cm and its height is 4 cm, find its volume.