Can any one help with this Fluid mechanics question please?

[jami8337]

Homework Statement

A shaft of diameter 74.9mm rotates at 1400rpm in a bearing which is of diameter 75.03 mm and 75mm in length. The annular space between the shaft and the bearing is filled with oil of viscosity 0.096 kg/ms.By assuming a uniform velocity gradient in the oil, determine the power required to overcome the viscous resistance in the bearing.

Homework Equations

F=μ(ωR/l)2∏RL

Thats the equation i have been using, where l is the difference between the radius of the outer ring and inner ring (i.e. bearing and shaft)

The Attempt at a Solution

When i plug in the values i get:
0.096* ((146.61*37.45*10^-3)/0.065*10^-3)*2∏*(37.45*10^-3)(75*10^-3)

this gives 143.12N

Presuming that this is all ok i then have no idea how to get to a power?
thanks

 

[SteamKing]

How much torque would this force produce on the shaft when it is turning at 1400 rpm? Once you know the torque, you can find the power.

 

[jami8337]

Ah yeah thanks got the right answer :)