1. The problem statement, all variables and given/known data Two balls are thrown upwards from the same spot 1.15 seconds apart. The first ball had an initial velocity of 15.0 m/s and the second was 12.0 m/s. At what time do they collide? 2. The attempt at a solution a = first ball b= second ball For them to collide, their height must be the same: da = db Via x ta + (0.5)(-9.81)(ta^2) = Vib tb + (0.5)(-9.81)(tb)2 (15 m/s) x (t) + (0.5)(-9.81)(t2) = (12 m/s)(t-1.15) + (0.5)(-9.81)(t-1.15)2 When I solve for t, I get 0.78 seconds... I know that this is incorrect. I don't know where I went wrong, it might be in how I set up the equation.