Mensurationmedium · Past Paper
If the radius of a sphere is halved, what is the ratio of the surface area of the original sphere to the new one?
A2:1
B4:1
C1:4
D8:1
✓ Correct Answer: B — 4:1
Area A ∝ r². Original: A, New: (1/2)²A = 1/4 A. Ratio = 1 : (1/4) = 4:1.
Share this question
More from Mensuration
- The area of a circle inscribed in a square of side 14 cm is:
- A pyramid has a volume of 100 cm³. If its height is 12 cm, find the area of its base.
- Find the volume of the largest right circular cone that can be cut out of a cube whose edge is 9 cm.
- If the diameter of a sphere is 14 cm, what is its surface area?
- If the radius of the base of a cone is halved, keeping the height same, what is the ratio of the volume of the reduced cone to that of the original cone?