Question

A viscous fluid of density 1050 kg m−3 and viscosity 12×10−4 Pa s flows through a pipe with a diameter of 5.0 cm.
What is the maximum speed at which the fluid can flow where the flow can be guaranteed to be laminar? (to 2 s.f and in m s−1)

Answer 1

$$Re=\frac{\rho dv}{\eta}=10$$

$$\frac{(1050)(0.05)v}{12\cdot10^{-4}}=10$$

$$v=2.3\cdot10^{-4}\frac{m}{s}$$