The instant before a squishy ball of mass meets a horizontal floor and comes to rest in time ?t it has momentum p = p0 (ˆi −ˆj ) .What average force does the floor exert on the ball in order to stop it during this time interval?

2 answers

it is in magnitude twice momentum, however, not knowing the rebound angle, I don't know which direction (i,r) reverses.
po/t (j-i)