Find the volume of a conical tank with the following dimensions in liters:
(a) Radius is 7cm and the slant height of the cone is 25 cm
(b) Slant height is 12cm and height is 13 cm
(a) It is given that
Radius of the cone(r) = 7 cm
Slant height of the cone (l) = 25 cm
As we know that,
$1^{2}=r^{2}+h^{2}$
$\mathrm{h}=\sqrt{1^{2}-\mathrm{r}^{2}}$
$\mathrm{~h}=\sqrt{25^{2}-7^{2}}$
$=\mathrm{r}=\sqrt{625-49}$
= 24 cm
Volume of a right circular cone
$=1 / 3 \pi r^{2} h$
$=1 / 3 * 3.14 * 7^{2} * 24$
$=1232 \mathrm{~cm}^{3}=1.232$ litres $\left[1 \mathrm{~cm}^{3}=0.01 \mathrm{l}\right]$
(c) It is given that:
Height of the cone (h) = 12 cm
Slant height of the cone (l) = 13 cm
As we know that,
$\mathrm{I}^{2}=\mathrm{r}^{2}+\mathrm{h}^{2}$
$r=\sqrt{1^{2}-h^{2}}$
$r=\sqrt{13^{2}-12^{2}}$
$=\mathrm{r}=\sqrt{169-144}=\sqrt{25}$
= 5 cm
Volume of a right circular cone:
$=1 / 3 \pi r^{2} h$
$=1 / 3 * 3.14 * 5^{2} * 10=314.85 \mathrm{~cm}^{3}=0.307$ litres $\left[1 \mathrm{~cm}^{3}=0.011\right]$