A cylindrical roller 300mm diameter and a mass of 50kg. rest on a horizontal floor with its curved surface against the edge of a horizontal step 75mm high and parallel to the axis of the roller. The coefficient of friction between the roller and the step is 0.25. Find the magnitude of the torque about the axis of the roller which will suffice to rotate it in contact with: 1. The step. 2. The edge of the step only.

A cylindrical roller 300mm diameter and a mass of 50kg. rest on a horizontal floor with its curved surface against the edge of a horizontal step 75mm high and parallel to the axis of the roller. The coefficient of friction between the roller and the step is 0.25. Find the magnitude of the torque about the axis of the roller which will suffice to rotate it in contact with: 1. The step. 2. The edge of the step only.

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.81P: Calculate the horizontal force P required to push the 85-lb lawn mower at constant speed. The center...

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