A man pulls up box of mass 70kg using an inclined plane of effective length 5m onto a platform 2.5m high at uniform speed. If the frictional force between the box and the plan is 100N draw the diagram of all the forces acting on the box when in motion and calculate the (a) minimum effort applied in pulling up the box (b) velocity ratio of the plane (c) machanical advantage of the plane

A man pulls up box of mass 70kg using an inclined plane of effective length 5m onto a platform 2.5m high at uniform speed. If the frictional force between the box and the plan is 100N draw the diagram of all the forces acting on the box when in motion and calculate the (a) minimum effort applied in pulling up the box (b) velocity ratio of the plane (c) machanical advantage of the plane

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 7.78P: The figure shows a steel bar being processed by a rolling mill. Given that P=80kN and r =0.016,...

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