If the ball matches the sticks and bean again, what will happen? If you say sticks will recover to the right, you are correct. We can think of this as a collision. When two collision objects, they do force. And every Newton, the same troops, keeping the total momentum with the bat system. We define the momentum as a product of mass and fifth objects again, the only way for a momentum to be nominated for the stick to stick to dip. (I know, this experiment setup will make a pretty spectable sport, but it remains to help me know what happens to the sweet spot). The ball re-launches back to the stick. However, this time, aim at the end instead of the center. Like this: The stick can still be recovered on the right, but now it also plays in the middle, Ta? Why is this happen? Also, a momentum is still preserved, but now there is a more protected angular momentum. A lot of angular momentum is like an empty old momentum, except for the rotation movement than the linear movement. The moment of Inertia is like a rotate mass – it is not just one of the objects, but how is the mass distributed. So, after the stick recovered from ball impact, clearly have axis, because of a play-roll on the collision? The stick does not play and do not have a angular momentum, so the angular momentum is to be preserved, the ball has to have a corner momentum. Yes, Mass can have an angular momentum even if you don’t play. (This is one of the time when physics is as strange.