1. The problem statement, all variables and given/known data Part 1: I've worked out part 1 already. The answer is 4650m/s^2 A ball travels vertically downwards until it hits a concrete floor with speed 22.7-m/s. It then bounces vertically upwards at 10.8-m/s. Examination of a high speed video shows that the collision took 7.2-ms. Considering just the collision, what is the magnitude of the average acceleration? Part 2: For some balls, the acceleration of the center of the ball, in a collision like this, is fairly constant. So, assuming constant acceleration, what is the maximum deformation of the ball? (i.e. what is the maximum distance that the center of the ball travels downwards?) 2. Relevant equations The 0 next to x and v are subscripts. x=x0+v0*t+0.5*a*t^2 Rearranged into: -(v0*t+0.5*a*t)=x0 3. The attempt at a solution I basically just subbed in the values. x0=-(-22.7*7.2*10^-3 +0.5*-4650*(7.2*10^-3)^2) =0.283968 Aprox. 0.284 Apparently, my answer is wrong.