Surface Areas and Volumes — Question 7

Given,

Diameter of the hemispherical ball (d) = 10.5 cm

Radius of the hemispherical ball (r) = $\dfrac{\text{Diameter}}{2} = \dfrac{10.5}{2}$ cm = 5.25 cm

By formula,

Volume of the hemispherical ball (V) = $\dfrac{2}{3}πr^3$

Substituting values we get :

$V = \dfrac{2}{3} \times \dfrac{22}{7} \times (5.25)^3 \\[1em] = \dfrac{44}{21} \times 144.703 \\[1em] = \dfrac{6366.9375}{21} \\[1em] = 303.1875 \\[1em] = \dfrac{303.1875}{1000} (∵ 1000 \text{ cm}^3 = 1 \text{ L}) \\[1em] = 0.3031875 \\[1em] \approx 0.303 \text{ l}$

Hence, the hemispherical bowl can hold 0.303 litres of milk.