State True or False: The ratio of whole surfaces of a solid sphere and a solid hemisphere of equal radius is 2 : 1.
WBBSE
Class X
Mathematics
Sphere
01 Mark
2024
False
Explanation:
Whole surface of sphere = 4πr².
Whole surface of hemisphere = curved (2πr²) + base (πr²)
= 3πr²
Ratio = 4πr² : 3πr² = 4 : 3 (not 2 : 1).
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