The drainage tile is a cylindrical shell with:
- Length = 21 cm
- Outside diameter = 5.1 cm
- Inside diameter = 4.5 cm
The outside radius R=25.1=2.55 cm
The inside radius r=24.5=2.25 cm
The volume of clay is the volume of the outer cylinder minus the volume of the inner cylinder.
Volume of clay =πR2h−πr2h
=πh(R2−r2)
Calculate R2:
R2=(2.55)2=6.5025
Calculate r2:
r2=(2.25)2=5.0625
Find the difference:
R2−r2=6.5025−5.0625=1.44
Volume =π×21×1.44
=30.24π cm³
Therefore, the volume of clay required is 30.24π cm³.