Let’s now look at calculating the weight of an object by using it’s volume. In the example below we are asked to calculate the weight of a solid aluminum rod. After measuring with our tape measure, we find that the height of the rod is 9 feet, and that the radius is 4 feet. Calculating the volume of a solid cylinder requires that we multiply the value of pie, times the radius squared, and times the cylinder’s height. Substituting the measured values we get the value of pie, which is 3.14, times four squared, times 9 for a total volume of 452.15 cubic feet. Using a different chart that provides the weight per volume of a material, as shown on this page, we now multiply the weight per volume for aluminum, by the volume calculated, which gives us 452.16 cubic feet, times 165 pounds per cubic feet, for a calculated weight of 74,606.4 pounds. Using this calculated weight, we can now begin to choose the rigging equipment, that will be able to withstand when carrying this weight.
