Question

A medicine capsule is in the shape of a cylinder with two hemispheres stuck to each of its ends. The length of the entire capsule is 14 mm and the diameter of the capsule is 5 mm. Find its surface area.

Answer 1

Height of cylinder $=14–5=9$ mm,
Radius, r $=2.5$ mm
Curved surface area of cylinder
$=2\pi rh$
$=2\pi \times 2.5\times 9$
$=45\pi m{m}^2$
Curved surface area of two hemispheres
$=2\times 2\pi r^2$
$=4\pi \times {2.5}^2$
$=25\pi m{m}^2$
Total surface area:
=Curved surface area of cylinder + Curved surface area of two hemispheres
=$45\pi +25\pi$
$=70\pi =220m{m}^2$