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Question
The total surface area of a cylinder whose radius is `1/3` of its height is
Options
`(9pi"h"^2)/8` sq.units
24πh2 sq.units
`(8pi"h"^2)/9` sq.units
`(56pi"h"^2)/9` sq.units
Solution
`(8pi"h"^2)/9` sq.units
Explanation;
Hint:
Let the height of the cylinder be "h"
Radius of the cylinder = `1/3` h
T.S.A of the cylinder = 2πr(h + r)
= `2pi xx "h"/3 ("h" + "h"/3)`
= `2pi xx "h"/3 ((4"h")/3)`
= `(8pi"h"^2)/9` sq.units
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