Answer: length of wire = 500cm
Step-by-step explanation:
We would determine the volume of material used in making the hollow cylindrical iron pipe by subtracting the volume of the inner pipe from the volume of the outer pipe.
The formula for determining the volume of a cylinder is expressed as
Volume = πr²h
Volume of inner pipe = π × 6² × 35 = 1260π
Volume of outer pipe = π × 8² × 35 = 2240π
Volume of material used in making the hollow cylindrical iron pipe is
2240π - 1260π = 980πcm³
The solid wire made is cylindrical and has a thickness of 2.8cm. This is the diameter. It means that the radius of the wire is 2.8/2 = 1.4cm
Volume of wire = 980πcm³
Applying the volume of cylinder formula, it becomes
980π = π × 1.4² × h
where h = length of wire
h = 980/1.4² = 500cm
