Expert: Zander Berlinski - 6/13/2009

Question
Could you explain for my dad and I why a lacrosse ball has an unusual bounce pattern.  If you fling it on cement, it has one normal bounce, then it springs up and flies on bounce 2, then 3 and maybe 4 are even again, then 4 (sometimes 5) whack back out with an odd trajectory.
Is there anything in that ball other than rubber?  And, what is the physics of that ball making it do that?

Thanks very very much

Answer
    Lee,
A lacrosse ball is the solid rubber ball that is used to play lacrosse. It is typically white, but can be many other colors, including black. It is usually between 7.75 and 8 inches (19–20 cm) in circumference (about 2.5 inches (6.5 cm) in diameter) and weighs between 5 and 5.25 ounces (140–150 g). As for the physics behind the way the ball bounces I can't answer that. I am sorry but that is outside my expertise.

Hope this helps and feel free to ask if you have any further questions. Also be sure to checkout www.zblax.com for all your lacrosse needs.

Thanks,
Zander