7. A ladder of length 12 m leaning up against a wall makes a 50 degree angle with the ground. The top of the ladder has sliders so that it can slide up and down the wall. Therefore, consider the top of the ladder to be frictionless. The ladder has a weight of 189 N that acts at its center. Someone weighing Fg = 1000 N is 0.92 m vertically below B, but on the ladder. Another person is on the ground holding the ladder by pushing on it horizontally with a force F. If the coefficient of static friction is 0.32, find the horizontal force F that must be applied at a vertical height of 1.2 m to prevent the ladder from slipping. F 2 m 12 m 50⁰ Fg B .92 m

7. A ladder of length 12 m leaning up against a wall makes a 50 degree angle with the ground. The top of the ladder has sliders so that it can slide up and down the wall. Therefore, consider the top of the ladder to be frictionless. The ladder has a weight of 189 N that acts at its center. Someone weighing Fg = 1000 N is 0.92 m vertically below B, but on the ladder. Another person is on the ground holding the ladder by pushing on it horizontally with a force F. If the coefficient of static friction is 0.32, find the horizontal force F that must be applied at a vertical height of 1.2 m to prevent the ladder from slipping. F 2 m 12 m 50⁰ Fg B .92 m

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 7.72P

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