Mensurationmedium · Past Paper
A right circular cylinder and a sphere have the same radius 'r'. If their surface areas are equal, the height of the cylinder is:
Ar
B2r
C3r
D1.5r
✓ Correct Answer: A — r
Actually, 2πrh + 2πr² = 4πr² => 2πrh = 2πr² => h = r. Wait, 'surface area of cylinder' usually means TSA unless CSA is specified. 2πrh + 2πr² = 4πr² => h = r.
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