Question

If the total surface area of a solid hemisphere is 462 cm2, find its volume.

Answer 1

since area of sphere is 462 which is = 4 pi r^2
from this find out r and put in volume formula 4/3 pi r^3 answer=929.4

Answer 2

Total surface area of the hemisphere = $\sf{{3πr}^{2}={462}^{2}}$

$\longrightarrow$$\sf{{r}^{2}=\frac{462×7}{3×22}=7×7}$

$\longrightarrow$${\boxed{\sf{r=7cm}}}$

Hence, the volume of the hemisphere

$\longrightarrow$$\sf{ \frac{2}{3} \pi {r}^{ 3} = \frac{2}{3} \times \frac{22}{7} \times 7 \times 7 \times 7 {cm}^{3}}$

$\longrightarrow$$\sf{{718.67cm}^{2}(Approx.)}$