Question

If the surface area of a sphere is 314 sq cm find its volume. (Take π = 3.14)

Answer 1

Radius of the sphere (r) =?
Surface area of the sphere = 314 sq cm
Surface area of a sphere = 4πr²
⇒ 314 = 4 × 3.14 × r²
$$\begin{gathered} \Rightarrow r^2=\frac{314}{4\times 3.14} \\ \Rightarrow r^2=25 \\ \Rightarrow r=5\mathrm{cm} \end{gathered}$$
Volume of sphere = $\frac{4}{3}\mathrm{\pi }{r}^3$
$$\begin{gathered} =\frac{4}{3}\times 3.14\times 5\times 5\times 5 \\ =523.33\mathrm{cu}\mathrm{cm} \end{gathered}$$