1. The problem statement, all variables and given/known data A 12kg shopping cart rolls due south at 1.5m/s. After striking the bumper of a car, it travels at 0.80m/s at 30. degrees E of South. What is the magnitude and direction of the change in momentum sustained by the shopping cart? 2. Relevant equations p = mv 3. The attempt at a solution initial py = mv = 12kg * 1.5m/s = -18N initial px = 0 final py = mv = 12kg * sin30 * 0.8m/s = -4.8N final px = 12kg * cos30 * 0.8m/s = 8.31N change in py = -4.8 + 18+ = 13.2N change in px = 8.31N magnitude of change in p = square root of (13.2N2 + 8.31N2) = 16N angle of change in p = tan-1(13.2N/8.31N) = 58 degrees North of East What am I doing wrong?