If a gold that has mass of 71.84g is drawn out into a cylindrical fiber of radius 3.500 µm.?

Question

what is the length of the fiber?

Answer 1

Use 19.3g/cm^3 for density of gold

Volume of a cylinder is (pi)(r^2)(L)

Volume also = Mass / Density

Volume(gold) = 71.84g / 19.3g/cm^3 = 3.7223cm^3

Length = Volume / pi(r^2) = 3.7223cm^3 / (3.14)(3.5µm)^2

= 96,770,000,000 cm

= 967,700 kilometers

Answer 2

First, figure out the VOLUME of the initial lump of gold. To do this, you'll need to know the density of gold, and then use the usual formula that relates mass, density and volume.

Next, use the fact that the volume before stretching will be the same as the volume after stretching. Use the formula that relates the diameter, length and volume of a cylinder; and solve for length.