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Question
The ratio of the total surface area of a sphere and a hemisphere of same radius is
Options
2 : 1
3 : 2
4 : 1
4 : 3
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Solution
In the given question,
The total surface area of a sphere (S1) = 4 \[\pi r^2\]
The total surface area of a hemisphere (S2) = 3 \[\pi r^2\]
So the ratio of the total surface area of a sphere and a hemisphere will be,
`S_1/S_2 = (4 pi r^2)/ (3 pi r^2)`
`= 4/3`
Therefore, the ratio of the surface areas is 4: 3 .
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