V = 15 m/s what happe 15-39. A ballistic pendulum consists of a 4-kg wooden block originally at rest, 0=0. When a 2-g bullet strikes and becomes embedded in it, it is observed that the block swing upward to a maximum angle of 0=6. Estimate the initial speed of the bullet. ex th th fri skateboard with he distances the re momentarily 0 1.25 m 01.25 m ling resistance. Prob. 15-39 g the 1.5-Mg car y at rest and the when the cable is truck and the car the loss of energy. *15-40. The boy jumps off the flat car at A with a velocity of v = 4 ft/s relative to the car as shown. If he lands on the second flat car B, determine the final speed of both cars after the motion. Each car has a weight of 80 lb. The boy's weight is 60 lb. Both cars are originally at rest. Neglect the mass of the car's wheels. v = 4 ft/s 1 t B 13 5 12 A