A uniform slender bar AB with a mass of 20 kg and length of 3.6 m leans on a wall as shown. It is attached to a weightless small roller at end A on a smooth horizontal surface. The coefficient kinetic friction between end B and the wall is 0.25. If the bar is released from rest in the position shown when θ is 30°. Then find, determine the normal force at A. determine the normal force at B. determine the frictional force between end B and the wall.

A uniform slender bar AB with a mass of 20 kg and length of 3.6 m leans on a wall as shown. It is attached to a weightless small roller at end A on a smooth horizontal surface. The coefficient kinetic friction between end B and the wall is 0.25. If the bar is released from rest in the position shown when θ is 30°. Then find, determine the normal force at A. determine the normal force at B. determine the frictional force between end B and the wall.

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 7.3P: Two identical chairs, each weighing 14 lb, are stacked as shown. The center of gravity of each chair...

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