Question

A cylindrical tube open at both ends is made of iron sheet which is 2 cm thick.if the outer diameter is 16cm and its length is 100cm long, find how many cubic centimetre of iron has been used making in sheets

Answer 1

length  of the pipe(H)=100 cm 
outer diameter of pipe =16
outer radius(R)=16cm
thickness of the pipe=2 cm
inner radius(r)=16-2=14 cm
volume of the metal used in making the tube 
πR²h-πr²h
3.14*100(16²-14²)    
18840 cm³
0.01884 m³