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):

A) \[f=\text{8/Re}\]           

B) \[f=16\text{/Re}\]

C) \[f=32\text{/Re}\]                      

D) \[f=64\text{/Re}\]