6) A lubricant oil with dynamic viscosity of 0.38 N-s/m²is used between two cylindrical shafts. The shafts are4 m long. The outer shaft has a radius of 0.015 mand the inner shaft has a radius of 0.014 m. A force of 10 N is required to rotate the inner shaft counterclockwise while the outer shaft remains fixed. What is0.014 m.0.015 m the linear speed of the rotating shaft? Assume a linear velocity profile between the shafts and that the oil behaves as a Newtonian fluid.

Fig: 1