I have a question that I can't quite get a handle on the physics of, perhaps
bedause it involves some properties of materials that I am not aware of.
When one takes a light stick or a piece of uncooked spaghetti and holds it near
the ends and flexes it it sometimes does not break into two pieces but into
three. You end up with one piece in each hand and a short middle section
which flies off as a projectile.
Why?
It would seem to me that a single break could be explained by considering
two forces or torques in opposite direction causing bonds to break, but why would it happen two different places? Unless they are somehow constrained to be
simultaneous it seems that the first break would relieve any stress on the
remaining free end so it should not break a piece off.
Any clues would be appreciated.
Jim Braunsdorf