Why does broken glass seem to be the sharpest thing on the planet? Even the smallest piece can stick in your foot and cause the worst discomfort. Is anything sharper than broken glass?
In: 2
Plenty of things are sharper than broken glass. Glass is sharp because it *doesn’t* bend. A metal edge is soft so it can [roll or blunt](https://qph.cf2.quoracdn.net/main-qimg-e329f114bb9ad9a52f45f6029aa4c64c.webp) as force is applied to the steel. Glass is very *hard*. That’s what makes it so brittle. It will *not* bend, so it shatters instead.
When it does shatter, it breaks along shear lines that leave those sharp edges. Something like metal will [bend as it breaks](https://makeagif.com/gif/tensile-testing-a-stainless-steel-tensile-specimen-hOWxdm) so there isn’t a clean break line.
[removed]
An object becomes sharp when it can maintain a thin edge without bending too much against pressure. Glass is very brittle and inflexible, which gives it the potential to become extremely sharp. Keep in mind that if something is too brittle to withstand a decent amount of force, it won’t matter how sharp it can get because it will lose its structural integrity without being able to cut much. Materials like steel and iron have the desirable ratio of sharpness to durability/flexibility, which is why they’re used so often when making cutting implements. You can take a glass knife and theoretically sharpen it to an impossibly fine edge, but it would shatter very easily. You don’t want the sharpness of your blade to exceed the durability of its material.
Sure, many things are sharper than glass. Some, like obsidian (a glass like stone) are sharp for the same reason, and others are edges that can be formed to a sharper edge through a more complex process than fracturing.
Latest Answers