Question

The Height Of A Cone Is$16cm$ And Its Base Radius Is $12cm$ $(\mathrm{\pi }=3.14)$. Find Its Curved Surface Area.

Answer 1

Curved Surface Area of cone

$CSA=\mathrm{\pi rl}$

$$\begin{gathered} l=\sqrt{h^2+r^2} \\ l=\sqrt{{16}^2+{12}^2} \\ l=\sqrt{256+144} \\ l=\sqrt{400} \\ l=20cm \end{gathered}$$

Now $CSA=\mathrm{\pi rl}$

$$\begin{gathered} CSA=3.14\times 12\times 20 \\ CSA=753.6c{m}^2 \end{gathered}$$

Therefore, the CSA of the cone is $753.6c{m}^2$.