Consider a horizontal pipe in which a viscous fluid is moving at a laminar flow. The pressure drop across a 0.2-cm ID pipe was measured at 18,000 Pa/m. The fluid has a = 1110 kg/m andu = 0.03 kg/m-s. Determine the equation that defines the velocity profile vz(r). Then, calculate the velocity at the center of the pipe (vz at r = 0 in m/s). (10 pts)

Fig: 1