D) is one quarter as much as before

D) is one quarter as much as before. E) is one third as much as before. 2. A girl of mass 44 kg throws a ball of mass 0.30 kg against a wall. The ball strikes the wall horizontally with a speed of 30 m/s, and it bounces back with this same speed. The ball is in contact with the wall 0.050 s. What is the magnitude of the average force exerted on the wall by the ball? A) 26,400 N B) 360 N C) 52,800 N D) 13,200 N E) 180 N 3. A car heading north suddenly collides at an intersection with a truck of the same mass heading east. If they lock together and travel at 28 m/s at 26 north of east just after the collision, how fast was the car initially traveling? A) 19 m/s B) 50 m/s C) 25 m/s D) 13 m/s 4. In the figure showing an isolated system, determine the character of the collision. The masses of the and the velocities before and after, are shown. The collision is 2.1 m/s 0.6 m/s 1.5 m/s 1.5 m/s 9 kg 3 kg 3 kg 3 kg Before After A) partially inelastic. B) completely inelastic. C) perfectly elastic. D) characterized by an increase in kinetic energy. E) not possible because momentum is not conserved. ar traveling north at