2. There are three pillbox hats labelled as shown containing toothpaste such that the masses of hats A, B and C are 2.5 kg, 3.7 kg, and 1.3 kg respectively. The system is released from rest and the coefficient of kinetic friction is 0.1 between the table and the hats. A) Find the tension in the string connecting the two hanging hats B and C. B) How far down does hat C travel between 0.1 seconds after release and 0.2 seconds after release? A

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 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 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? %3D r = 1.25 ft P = 10 lbs r2 = 0.75 ft

5) A block weighing 50 lb is shown on an inclined surface. The block is released from rest at the po- sition shown. The spring has a spring constant of k = 10 lb/in., and the coefficient of friction be- tween the block and the incline is 0.3. What is the maximum compression of the spring? 6) For the system in Question 5, what is the velocity of the block the moment it leaves the spring? 50 lb 10' 30° K www. Page 1 of 2