3) A 50-lb spool with outer radius of 15 inches, inner radius of 9 inches, and moment of inertiaof 0.8 slug-ft? is initially at rest. If a 10-lb force, P, is applied at the inner radius of the spool asshown. The coefficients of static and kinetic friction between the cylinder and the ground atpoint A are us = 0.3 and µk = 0.25 respectively.a) Draw the FBD and IRD of the system.b) Determine the acceleration of the center of mass, G, in ft/s². Assume the wheel is rollingwithout slipping. [Ans. to Check: a = -7.75 i ft/s²]c) Check the assumption of rolling without slip. Was this a valid assumption?%3Dr = 1.25 ftP = 10 lbsr2 = 0.75 ft

a).Draw free body diagram of the system

3) A 50-lb spool with outer radius of 15 inches, inner radius of 9 inches, and moment of inertia of 0.8 slug-ft? is initially at rest. If a 10-lb force, P, is applied at the inner radius of the spool as shown. The coefficients of static and kinetic friction between the cylinder and the ground at point A are us = 0.3 and uk = 0.25 respectively. a) Draw the FBD and IRD of the system. b) Determine the acceleration of the center of mass, G, in ft/s². Assume the wheel is rolling without slipping. [Ans. to Check: a = -7.75 i ft/s²] c) Check the assumption of rolling without slip. Was this a valid assumption? r = 1.25 ft P = 10 lbs r, = 0.75 ft

3) A 50-lb spool with outer radius of 15 inches, inner radius of 9 inches, and moment of inertia of 0.8 slug-ft? is initially at rest. If a 10-lb force, P, is applied at the inner radius of the spool as shown. The coefficients of static and kinetic friction between the cylinder and the ground at point A are us = 0.3 and uk = 0.25 respectively. a) Draw the FBD and IRD of the system. b) Determine the acceleration of the center of mass, G, in ft/s². Assume the wheel is rolling without slipping. [Ans. to Check: a = -7.75 i ft/s²] c) Check the assumption of rolling without slip. Was this a valid assumption? r = 1.25 ft P = 10 lbs r, = 0.75 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 7.24P: A uniform plank is supported by a fixed support at A and a drum at B that rotates clockwise. The...

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