Question
In a cylinder, if radius is halved and height is doubled, the volume will be:
- Same.
- Doubled.
- Halved.
- Four times.
✓
Answer
- Halved.
Volume of cylinder $\text{V}=\pi\text{r}^2\text{h}$
If $\text{r}'=\frac{\text{r}}{2}$ and $\text{h}'=2\text{h}$ then
Then $\text{V}'=\pi\Big(\frac{\text{r}}{2}\Big)^22\text{h}$
$=\frac{\pi\text{r}^2}{\not4_2}\times\not2\text{h}$
$\frac{\pi\text{r}^2\text{h}}{2}=\frac{\text{V}}{2}$
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