Question

A wooden toy was made by scooping out a hemisphere of same radius from each end of a solid cylinder. If the height of the cylinder is 10 cm, and its base is of radius 3.5 cm, find the volume of wood in the toy $[Use\pi =\frac{22}{7}]$

Answer 1

Height of the cylinder = 10cm radius = 3.5 cm
Volume of wood in the toy =
Volume of cylinder - volume of 2 hemisphere
$\Rightarrow \pi r^{2}h-2\times \frac{2}{3}\pi r^3\Rightarrow \pi r^2(10-\frac{4}{3}r)\Rightarrow \frac{22}{7}\times {3.5}^{0.5}\times 3.5(10-\frac{4\times 3.5}{3})\Rightarrow 11\times 3.5\left(\frac{30-14}{3}\right)=38.5\times \frac{16}{3}$