For a fixed mass flow rate of a given fluid flowing through a circular pipe, how does the specific frictional pressure loss (in j/kg) per unit pipe length vary with pipe diameter? derive the relationship between frictional loss per unit length and the pipe diameter for both the laminar region and the fully-turbulent region with a fixed ratio of roughncss (mm) to pipe diameter (mm). use your result to qualitatively describe the relationship for fully turbulent pipe flow with fixed roughness (mm).