5. The flow of water (mass density = 1000 kg/m3 and kinematic viscosity = 10-6 m2/s) in a commercial pipe, having equivalent roughness ks as 0.12 mm, yields an average shear stress at the pipe boundary = 600 N/m2. The value of ks/?' (?' being the thickness of laminar sub-layer) for this pipe is
10. A square column carries a load P at the centroid of one of the quarters of the square. If a is the side of the main square, the combined bending stress will be
