How physics can help you when you’re making your next soufflé.
We know that in life, you have to break a few eggs to make the proverbial omelette. But what does physics have to say about how it’s done?
The geometry of an ovoid (an egg shape) brings with it particular combinations of rigidity and strength, depending on how you apply your outside force. A couple of new studies in Physical Review Letters looked at the cracking problem, devised some mathematical formulas to explain it, and noted why the crystalline calcium carbonate works so well for damage control. Jennifer Ouellette writes at Slate:
Eggshells aren’t quite as brittle as glass or the metal shell of an airplane, because they are laced with organic material. Any given material gets its properties, like resistance to cracking, from its crystalline structure. Eggshell is similar to tooth enamel or seashells; all of these materials are made up primarily of calcium carbonate (calcite) crystals embedded within a protein matrix. It’s the latter that gives the shell its remarkable toughness, which is bolstered by a thin inner membrane made of collagen. Rather than splitting an eggshell in one clean break, cracks in an eggshell spread bit by bit, millimeter by millimeter. “Cracks propagate with great difficulty and the eggshell doesn’t shatter,” says Michelle Oyen, a materials scientist at Cambridge University. “The damage is very localized.” In that respect, an eggshell is nature’s perfect packaging.
Or you could just blast it open with a cannon.
(via Slate Magazine)