Question
In a cylinder, if radius is doubled and height is halved, curved surface area will be:
✓
Answer
- Same.
curved surface area of a cylinder of radius 'r' and heightn 'h' is given by $\text{A}=2\pi\text{rh}$
Now, if r' = 2r and $\text{h}'=\frac{\text{h}}{2}$
Then $\text{A}'=2\pi\times(2\text{r})\times\frac{\text{h}}{2}$
$=2\pi\text{rh}=\text{A}$
⇒ C.S.A. remains the same.
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