Mensurationeasy · Past Paper
A metallic sphere of radius 10.5 cm is melted and recast into small cones of radius 3.5 cm and height 3 cm. This question relates to volume, but what is the total surface area of the original sphere?
A1386 cm²
B1400 cm²
C1500 cm²
D1286 cm²
✓ Correct Answer: A — 1386 cm²
TSA = 4πr² = 4 * (22/7) * 10.5 * 10.5 = 1386 cm².
Share this question
More from Mensuration
- The ratio of the radii of two cylinders is 1:√3 and their heights are in the ratio 2:3. Find the ratio of their volumes.
- The sum of length, breadth, and height of a cuboid is 19 cm and its diagonal is 11 cm. Find its volume if the surface area is not needed but related? (Wait, let's use a standard volume problem). A cuboid has dimensions in the ratio 3:2:1 and volume 1296 cm³. Find the length.
- A conical tent is 9 m high and its base radius is 12 m. What is the cost of canvas required at Rs. 100 per sq. m?
- Volume of a prism is given by:
- The ratio of the total surface area to the curved surface area of a cylinder is 3:2. If the total surface area is 462 sq. cm, find its volume.