# Diameter

Algebra

### Diameter

A piece of copper is 4 in. in length, 2 in. in width, and 1/2 in. thick is formed into a wire 100 yds. in length and uniform thickness. Find diameter of wire.

Volume of copper = 4 * 2 * .5 = 4 cu. in.

Length of wire = 100 * 3 * 12 = 3600 in.

Wire is a cylinder: Volume of cylinder = pi * r^2 * height or length.

3.1416 * r^2 * 3600 = 4

11309.76 * r^2 = 4

Not sure how to proceed - Where am I incorrect?
Guest

### Re: Diameter

$$3.1416 * r^2 * 3600 = 4$$

$$3.1416 * r^2 * 900 = 1$$

$$r^2 = \frac{1}{2827.44}$$

$$r = \frac{1}{53.174}$$

$$r = 0.019$$ in
Guest

Thanks.
Guest