Question

The volume of a right circular cone is $9856{cm}^3$. If the diameter of the base is 28 cm, find$\left(i\right)$height of the cone.$\left(ii\right)$slant height of the cone.$\left(iii\right)$Curved surface area of the cone.

Answer 1

Given diameter$2r=14\Rightarrow r=\frac{14}{2}$

V$=9856=\frac{1}{3}\times \pi r^{2}h$

$\frac{22}{7}\times \frac{{14}^2}{4}\times h^2=9856$

$h=48cm$

Slant height$=\sqrt{r^2+h^2}=\sqrt{{14}^2+{48}^2}=50cm$

curved surface area = $\pi rl=\frac{22}{7}\times 14\times 50$

$=2200c{m}^2$