Railways
NTPC (Technical Ability)
Fluid Mechanics and Machinery
Question Bank
Fluid Mechanics
question_answer
Darcy-Weisback equation for the head loss in a flow through a pipe is given by \[{{h}_{1}}=4\,fl{{v}^{2}}\] (2gd) (the symbols have the usual meaning). For the laminar flow through a circular pipe, how does the friction factor \[f\] vary with the Reynolds number (Re):