A cylinder has a diameter of 20 cm. The area of curved surface is 1000 cm2. Find (i) the height of the cylinder correct to one decimal place. (ii) the volume of the cylinder correct to one decimal place. (Take π = 3.14)
A cylinder has a diameter of 20 cm. The area of curved surface is 1000 cm2. Find (i) the height of the cylinder correct to one decimal place. (ii) the volume of the cylinder correct to one decimal place. (Take π = 3.14)

Solution:

(i) Given diameter of the cylinder, d = 20 cm

Radius, r = d/2 = 20/2 = 10 cm

Curved surface area = 1000 cm2

2rh = 1000

2×3.14×10×h = 1000

62.8h = 1000

h = 1000/62.8

= 15.9 cm

Hence the height of the cylinder is 15.9 cm.

(ii)Volume of the cylinder, V = r2h

= 3.14×102×15.9

= 4992.6 cm3

Hence the volume of the cylinder is 4992.6 cm3.