1. Atmospheric air at 25-C flows in a 2-cm-diameter horizontal pipe at Re ¼ 1600. Calculate the wall shear stress, the friction factor, the head loss, and the pressure drop over 20 m of pipe.
2. A liquid flows in a 4-cm-diameter pipe. At what radius does the velocity equal the average velocity assuming a laminar flow? At what radius is the shear stress equal to one-half the wall shear stress?