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Question
If the height of a cylinder becomes `1/4` of the original height and the radius is doubled, then which of the following will be true?
Options
Total surface area of the cylinder will be doubled.
Total surface area of the cylinder will remain unchanged.
Total surface of the cylinder will be halved.
None of the above.
Solution
None of the above.
Explanation:
We know that,
Total surface area of cylinder having radius r and height h = 2πr (h + r)
Total surface area of the cylinder with new height `(h/u)` and radius 2r
= `2pi(2r) (2r + 1/4 h)`
= `4pir (8r + h) xx 1/4`
= πr (8r + h)
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