Question

A copper refinery produces a copper ingot weighing 150 lb.

If the copper is drawn into wire whose diameter is 7.00 mm , how many feet of copper can be obtained from the ingot? The density of copper is 8.94 g/cm3.

Answer 1

Given ingot of Cu = 150 lb

mass of Cu ingot = 150 lb * 453.592 g/lb

mass of Cu = 68038.9 g

volume of cu wire from density is given by,

v = m/d ( where m = mass of Cu and d = density of the Cu)

v = 68038.9g/(8.94g/cm^3)

v = 7610.615 cm^3

we have the diameter of the wire = 7 mm

radius of the wire = 7/2 = 3.5 mm = 0.35 cm

from the formula volume of the cylinder,

V = 3.14*r^2*h

V = volume of the cylinder = 7610.615 cm^3

r = radius of the cylinder = 0.35 cm

h = length of the cylinder in cm

7610.615 = 3.14 * (0.35)^2 * h

h = 19875.82 cm

we know that 1 cm = 0.03281 feet

length of the Cu wire = 19875.82 cm * 0.03281 feet/cm

length of the Cu wire = 652.94 feet