4. The mine car and its contents have a total mass of 6000 kg and a centre of gravity at G. If the coefficient of static friction between the wheels and the tracks is u = 0.4 when the wheels are locked, find the normal force acting on the front wheels at B and the rear %3D wheels at A when the brakes at both A and B are locked. Does the car move? [Ans. NA = 16.5 kN, Ng =42.3 kN, the car does not move]

4. The mine car and its contents have a total mass of 6000 kg and a centre of gravity at G. If the coefficient of static friction between the wheels and the tracks is u = 0.4 when the wheels are locked, find the normal force acting on the front wheels at B and the rear %3D wheels at A when the brakes at both A and B are locked. Does the car move? [Ans. NA = 16.5 kN, Ng =42.3 kN, the car does not move]

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 7.56P: The square-threaded screw 0f the C-clamp has a mean diameter of 8 mm and a pitch of 1.6 mm. The...

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