Ok, I've done work on this problem, but I think that everything I try is wrong. I can't get any help from my book or my teacher because he made it up and wants up to try it. But I have no clue how to start. Please help me A basketball (m = 0.57 kg) is dropped from rest. Just before striking the floor, the magnitude of the basketball's momentum is 2.5 kgm/s. At what height was the basketball dropped?