Question

the volume of metallic cylindrical pipe is 748cm3 it's length is 14cm and it's external radius is 9cm . find its thickness

Answer 1

1)dimensions of a pipe
Height =h=14cm
Radius = r.cm
Given
Volume =748 cm^3
Pi*r^2*h=748
22/7*r^2*h=748

r^2 =(748*7)/(22*14)

r^2=17

r = root 17
r = 4(approximately)
Given external radius R= 9cm
Thickness of the pipe =9-4 =5cm

Answer 2

748=πh(R^2-r^2)

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

=748=44(9^2-r^2)

=748/44=9^2-r^2

=r^2=81-17

=r^2=64

=r^2=8^2

=r=8m

thickness=R-r

=9-8

=1cm