Some damping systems use a disk immersed in oil as a damper. if the viscosity of the oil is µ, determine the torque, t, needed to be applied to the shaft to maintain the system rotating at a constant angular speed ω. express your answer in terms of the viscosity of the fluid, the angular speed of the system, the radius of the disk r, and the separation distance between the disk and the upper (a) and lower (b) horizontal walls of the damper. neglect the thickness of the disk.