1. The problem statement, all variables and given/known data A 0.70 kg ball is moving horizontally with speed of 9.6 m/s when it strikes a vertical wall. The ball rebounds with speed of 1.3 m/s. What is the magnitude of the change in linear momentum of the ball? 2. Relevant equations Dp = mv(f) - mv(i) 3. The attempt at a solution I solved for mv(f) and mv(i). Solved for Dp which I got -5.81 which is wrong.