This problem involves a cylinder falling inside a pipe that is flled with oil, as depicted in the figure. The small space between the cylinder and the pipe is lubricated with an oil film that has absolute viscosity a. (a) Derive a formula for the steady rate of descent of a cylinder with weight W, diameter d, and length e sliding inside a vertical smooth pipe that has inside diameter D. Assume that the cylinder is concentric with the pipe as it falls. (b) Use tbe general formula you derive to find the rate of descent of a cylinder 100mm in diameter that slides inside a 100.5mm diameter pipe. The cylinder is 200mm long and weighs 15N. The lubricant is SAE 20W oil with a viscosity of 2.0 x 10-3Pas.

This problem involves a cylinder falling inside a pipe that is flled with oil, as depicted in the figure. The small space between the cylinder and the pipe is lubricated with an oil film that has absolute viscosity a. (a) Derive a formula for the steady rate of descent of a cylinder with weight W, diameter d, and length e sliding inside a vertical smooth pipe that has inside diameter D. Assume that the cylinder is concentric with the pipe as it falls. (b) Use tbe general formula you derive to find the rate of descent of a cylinder 100mm in diameter that slides inside a 100.5mm diameter pipe. The cylinder is 200mm long and weighs 15N. The lubricant is SAE 20W oil with a viscosity of 2.0 x 10-3Pas.