=R34Q where Q is the volumetric flow rate. (c) Calculate the water flow rate for the required shear stress (0.1Nm2) in the main section, ensuring that we have laminar flow, using equation (3) in part (b), or otherwise, for the 38 mm inside diameter pipe. If this flow is not laminar, used smaller tube sizes, in the order 38mm,32mm,25mm,19mm and 13mm, until the flow is laminar and the required wall shear stress is achieved. (d) Derive the relationship between wall shear stress and pressure drop per unit length, regardless of the fluid flow regime. LP=R2 (e) Using equations (3) and (4), calculate the length of 3mm inside diameter capillary tube to give the required flow rate in step (c)