Question

If the lateral surface of a cylinder is 94.2 $c{m}^2$ and its height is 5 cm, find :

(i) radius of its base

(ii) volume of the cylinder [Use $\pi$ = 3.14]

Answer 1

Lateral surface area of a cylinder = 94.2 $c{m}^2$

Height (h) = 5 cm

(i) Let r be the radius of the cylinder

$\therefore 2\pi$ rh = 94.2

$\Rightarrow 2\times 3.14\times r\times$ 5 = 94.2

$\Rightarrow r=\frac{94.2}{2\times 3.14\times 5}=\frac{94.2}{31.4}=3cm$

(ii) Volume of the cylinder = $\pi r^2$ h

= 3.14 $\times 3\times 3\times 5c{m}^3=141.3c{m}^3$