If a 1519 kg train car on a one dimensional track, moving at 6 m/s north, hits and bounces off a second train car with a mass of 2830 kg , moving at 10 m/s south, find the magnitude of the final speed of the first car (the second car will have a different speed, most probably in the opposite direction). Hint: One dimensional problem, call north positive. Use the "hit and bounce" or elastic formula that goes with car #1 decorative Also, a positive answer would indicate motion to the north and a negative answer would show southward motion - leave positive/negative in your answer.