Question

A hemispherical bowl is made od of steel 0.25 hick the inside radius is 5cm of the bowl find the volume of steel uses in making the bowl

Answer 1

Dear Student,

$$\begin{gathered} \mathrm{Internal}\mathrm{radius}\mathrm{of}\mathrm{hemispherical}\mathrm{bowl},\mathrm{r}=5\mathrm{cm} \\ \mathrm{Outer}\mathrm{radius}\mathrm{of}\mathrm{hemispherical}\mathrm{bowl},\mathrm{R}=5+0.25=5.25\mathrm{cm} \\ \mathrm{Volume}\mathrm{of}\mathrm{steel}\mathrm{used}\mathrm{in}\mathrm{making}\mathrm{the}\mathrm{bowl}=\mathrm{Outer}\mathrm{volume}-\mathrm{inner}\mathrm{volume} \\ =\frac{2}{3}{\mathrm{\pi R}}^3-\frac{2}{3}{\mathrm{\pi r}}^3 \\ =\frac{2}{3}\mathrm{\pi }\left({\mathrm{R}}^3-{\mathrm{r}}^3\right) \\ =\frac{2}{3}\times \frac{22}{7}\times \left(5.{25}^3-5^3\right) \\ =\frac{44}{21}\times \left(144.70-125\right) \\ =\frac{44\times 19.70}{21} \\ =41.27{\mathrm{cm}}^3\mathrm{ANS}... \end{gathered}$$

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