Dynamics PBM: Final Post

My hypothesis was correct. The object on the bottom transfer the momentum unto the object on top. When the basketball was on top, the tennis ball could only transfer its small momentum which caused the basketball to bounce up only a little higher than when by itself. So, when the tennis ball is on top, the large momentum of the basketball is transferred to the tennis ball, which is more than what this mass should have, thus the ball bounces very high.