Question

the volume of a mettalic cylindrical pipe is 748cm³.its length is 14cm and its external radius is 9cm. find the thickness

Answer 1

volume of cylinder = π x h x (R^2 - r^2) = 748

h = 14 cm

R = 9 cm

by putting the values in the equation we get,

22/7 x 14 x (9^2 - r^2) = 748

44 x (81 - r^2) = 748

81 - r^2 = 748 / 44 = 17

81 - 17 = r^2 ⇒ r^2 = 64

r = √64 = 8 cm

thickness = R - r = 9 - 8 = 1 cm