- #1

jami8337

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## 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