Question

A copper refinery produces a copper ingot weighing 150 lb. If the copper is drawn into wire whose diameter is 8.25mm, how many feet of copper can be obtained from the ingot? The density of copper is 8.94 g/cm^3. (Assume that the wire is a cylinder whose volume is V=3.14r^2h, where r is its radius and h is its height or length.

Answer 1

Please help!

Answer 2

you need to turn the 150lb into grams to find mass. Turn that mass into volume using the density of copper. Those cm^3 will be the same, whether the copper is in a brick, or stretched into a wire. So\[V = \pi *r^2*h\]
lets you find "h", the height of the cylinder (because that's what the wire is. a really, REALLY long cylinder with a tiny radius)

Answer 3

I get about 117 feet