A liquid drug, with viscosity and density of water, is to be administered through a hypodermic needle. The inside diameter of the needle is 0.25 mm and its length is 50 mm. Ignore minor head losses. Determine; a) The maximum volume flowrate Q for which the flow will remain laminar, e.g. Re<2000. b) The friction factor for the flow in part a) c) The pressure drop PA - PB across the needle for the flow in part a) 0.25 mm 50 mm Patm Plonger A

A liquid drug, with viscosity and density of water, is to be administered through a hypodermic needle. The inside diameter of the needle is 0.25 mm and its length is 50 mm. Ignore minor head losses. Determine; a) The maximum volume flowrate Q for which the flow will remain laminar, e.g. Re<2000. b) The friction factor for the flow in part a) c) The pressure drop PA - PB across the needle for the flow in part a) 0.25 mm 50 mm Patm Plonger A