Wednesday, September 21, 2005

Breaking spaghetti: Film at 11

How bent spaghetti breaks

Bent dry spaghetti do not break in half but instead in three or more pieces. With the aim to explain this surprising phenomenon, we studied a related problem, namely the dynamics of an elastic rod that is bent quasi-statically and then suddenly set free. Counter-intuitively, we find that the mere release of the rod induces a stress increase. The multiple breaking of bent rods, like dry spaghetti pasta, can then be understood as a cascade of releases (loss of cohesion upon breakings) followed by stress increases leading to new cracks.