A machine of mass M is to be moved over a level surface using a series of

Question:

A machine of mass M is to be moved over a level surface using a series of rollers for which the coefficient of rolling resistance is ag at the ground and am at the bottom surface of the machine. Determine the appropriate diameter of the rollers so that the machine can be pushed forward with a horizontal force P. Hint: Use the result of Prob. 8-131.

Units Used:

Mg = 1000 kg

Given:

M = 1.4 Mg

ag = 0.5 mm

am = 0.2 mm

P = 250 N