Question

The height of a cone is 16 cm and its base radius is 12 cm. Find the curved surface area and the total surface area of the cone (Use $\pi =3.14$).

Answer 1

R.E.F image

$OA=16cm,AB=l$

$l=\sqrt{{16}^2+{12}^2}=\sqrt{256+144}$

$l=20cm$

curved surface Area,

$C.S.A=\pi rl=3.14\times 12\times 20$$=753.6c{m}^2$

Total surface Area,

$T.S.A=\pi r(r+l)=3.14\times 12[12+20]$$=1205.76c{m}^2$