A copper pipe, used for plumbing from the water main to a house, is 5 meters long and has a circular cross-section 3.2 cm in diameter. There is a 2.4 cm diameter hole in the center of the cross-section for the entire length of the rod.
The cross-section area is pi*(1.6 cm)^2 - pi*(1.2 cm)^2 pi * (2.56 - 1.44) cm^2 3.51858 cm^2 The length of the pipe is 500 cm, so the volume of copper is 1759.3 cm^3 The number of cubic centimeters in a cubic foot is 28316.85, so the density of the copper is 0.01974 lb_m per cc Thus, the weight in pounds is 0.01974*1759.3 34.7 pounds
The cross-section area is pi*(1.6 cm)^2 - pi*(1.2 cm)^2 pi * (2.56 - 1.44) cm^2 3.51858 cm^2 The length of the pipe is 500 cm, so the volume of copper is 1759.3 cm^3 The number of cubic centimeters in a cubic foot is 28316.85, so the density of the copper is 0.01974 lb_m per cc Thus, the weight in pounds is 0.01974*1759.3 34.7 pounds
