Physics
Mechanics of Zipper Strength
Quick fact
The strength of a zipper is not simply about the material of the teeth; it is heavily influenced by the shape of the teeth and the way the slider guides them into interlocking. A well-designed zipper can distribute applied force across multiple teeth, making it stronger than any single tooth.
Why this is interesting
When you pull a zipper, you're not just moving a slider; you're engaging a tiny mechanical lock along a track. Why does a zipper sometimes split open with a slight pull, while other zippers can hold a heavy load?