If the rod were pinned at the center, it would rotate if hit at the end. If it were not pinned at the center, but were on a frictionless surface, would it just rotate? Hmm... No, I guess it wouldn't. The end point would want to move in a straight line along the direction of the initial impact. It would get more complicated along the length of the rod, I think. It's been too long for me to be confident of constructing a solution...

I'm thinking back on the video out there of the behavior of a slinky that's hanging vertically and then dropped. What happens to the end closest to the ground when the top is released? One can be mislead if one jumps to conclusions based on intuition...

http://www.youtube.c...OO0&v=uiyMuHuCFo4

Cheers,
Scott.