Problems 4.78 through 4.80 The crates A and B of weight WA by a pulley system. The system is released from rest and friction between A and the horizontal surface is insufficient to prevent slipping. The cables in the pulley system are inextensible, and the coefficient of kinetic friction between the crate A and the horizontal = 50 lb and WR = 75 lb, respectively, are connected surface is Problem 4.78 If u = 0, determine the speed of B after A slides 10 ft. Problem 4.79 Determine the required value of u so that the speed of B is 27 ft/s after it drops 15 ft. Figure P4.78-P4.80 Problem 4.80 If u = 0.25, determine the speed of A after B drops 15 ft.

Problems 4.78 through 4.80 The crates A and B of weight WA by a pulley system. The system is released from rest and friction between A and the horizontal surface is insufficient to prevent slipping. The cables in the pulley system are inextensible, and the coefficient of kinetic friction between the crate A and the horizontal = 50 lb and WR = 75 lb, respectively, are connected surface is Problem 4.78 If u = 0, determine the speed of B after A slides 10 ft. Problem 4.79 Determine the required value of u so that the speed of B is 27 ft/s after it drops 15 ft. Figure P4.78-P4.80 Problem 4.80 If u = 0.25, determine the speed of A after B drops 15 ft.

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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