Harold is a woodworker and is interested in finding the density of two different types of wood. He bought a pine log that has a 5-inch radius and is 30 inches long. The weight of the log is approximately 42.63 pounds. He also has an oak board that is 5.5 inches wide, 1.5 inches thick and 3 feet long. The board weighs approximately 8.05 pounds.

Equation for Density = Mass / Volume

Solving for density of log:

radius = 5 inches

Area of a circle = pi (radius) ^2 = (3.1415) (25 inches squared) = 78.53 inches squared

volume = area * length = (78.53 inches sqrd) (30 inches) = 2,356.125 cubic inches

log density = 42.63 lbs / (2,356.125 inches sqrd) = 0.018 lbs / cubic inch

Solving for density of Oak Board:

volume = (5.5 inch) (1.5 inch) (36 inch) = 297 cubic inches

board density = 8.05 lbs / 297 cubic inches = 0.027 lbs/cubic inch