Question
A medicine capsule is in the shape of a cylinder with two hemispheres stuck to each of its ends (see Fig. 13.10). The length of the entire capsule is 14 mm and the diameter of the capsule is 5 mm. Find its surface area.
Solution
Let r mm be radius of the hemisphere, then
Let r mm be the radius and h mm be the height of the cylinder, then
r1 = 2.5 mm
and h = (14 – 5) mm = 9 mm
Now,
Surface Area of Capsule
= CSA of cylinder + CSA of two
hemispherical ends = 2πr1h + 2(2πr2)
= (2πr1h + 4πr2) mm2
= (2πrh + 4πr2) mm2 [∵ r1 = r]
= [2πr (h + 2r)]mm2
Let r mm be the radius and h mm be the height of the cylinder, then
r1 = 2.5 mm
and h = (14 – 5) mm = 9 mm
Now,
Surface Area of Capsule
= CSA of cylinder + CSA of two
hemispherical ends = 2πr1h + 2(2πr2)
= (2πr1h + 4πr2) mm2
= (2πrh + 4πr2) mm2 [∵ r1 = r]
= [2πr (h + 2r)]mm2
