Question

A hemispherical bowl is made of steel, $0.25cm$ thick. The inner radius of the bowl is $5cm$. Find the outer curved surface of the bowl. (Assume $\mathrm{\pi }=\frac{22}{7}$)

Answer 1

The inner radius of the hemispherical bowl$=5cm$

The thickness of the bowl $=0.25cm$

The outer radius of the hemispherical bowl $=\left(5+0.25\right)=5.25cm$

We know, the formula for the outer curved surface area of a hemispherical bowl $=2{\mathrm{\pi r}}^2$, where r is radius of the hemisphere

$2{\mathrm{\pi r}}^2=2\times \frac{22}{7}\times 5.25\times 5.25=173.25c{m}^2$

Hence, the outer curved surface area of the bowl is $173.25c{m}^2$.