15-63. The four balls each have the same mass m. If A and B are rolling forward with velocity v and strike C, determine the velocity of each ball after the first three collisions. Take e=0.5 between each ball.

19-30. The 10-g bullet having a velocity of 800 m/s is fired into the edge of the 5-kg disk as shown. Determine the angular velocity of the disk just after the bullet becomes embedded into its edge. Also, calculate the angle 0 the disk will swing when it stops. The disk is originally at rest. Neglect the mass of the rod AB. 2 m v = 800 m/s 0.4 m

15-83. The 10-lb collar B is at rest, and when it is in the position shown the spring is unstretched. If another 1-lb collar A strikes it so that B slides 4 ft on the smooth rod before momentarily stopping, determine the velocity of A just after impact, and the average force exerted between A and B during the impact if the impact occurs in 0.002 s The coefficient of restitution between A and B is e=0.5. k = 20 lb/ft ? 3 ft

15-51. The 30-Mg freight car A and 15-Mg freight car B are moving towards each other with the velocities shown. Determine the maximum compression of the spring mounted on car A. Neglect rolling resistance

19-45. The 10-lb block is sliding on the smooth surface when the corner D hits a stop block S. Determine the minimum velocity v the block should have which would allow it to tip over on its side and land in the position shown. Neglect the size of S. Hint: During impact consider the weight of the block to be nonimpulsive. BE ft SHD

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When 0=60°, the boy's center of mass G has a speed of 10 ft/s as he swings to the right. Determine the rate of increase in his speed and the tension in each of the two supporting cords of the swing at that instant. The boy has a weight of 60 lb. 10 í