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Question
If two solid hemispheres of same base radius r are joined together along their bases, then curved surface area of this new solid is ______.
Options
4πr2
6πr2
3πr2
8πr2
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Solution
If two solid hemispheres of same base radius r are joined together along their bases, then curved surface area of this new solid is 4πr2.
Explanation:
Because curved surface area of a hemisphere is 2πr2 and here, we join two solid hemispheres along their bases of radius r, from which we get a solid sphere.
Hence, the curved surface area of new solid = 2πr2 + 2πr2 = 4πr2.
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