Darcy – weisbach equation for the head loss is a flow through a pipe is given by
h1 = 4 f1 v2/(2gd) (the symbols have the usual meaning). For the laminar flow through a circular pipe how does the friction factor f vary with a Reynolds number (Re)?
(a) f =8/Re (b) f = 16/Re (c) f = 32/Re (d) f = 64/Re