How Does Glass isn't a Solid or Liquid Work?

Glass isn’t really a solid or a liquid, it’s kind of in between.

Imagine you have a big block of ice. If you leave it out in the sun, it slowly melts into water. That's like a solid turning into a liquid. Now imagine that same block of ice, but instead of melting all at once, it just gets slower and slower, like it’s trying to decide what it wants to be.

That's kind of what glass is like. It was once molten rock or sand, heated up really hot until it became liquid. But then it cooled down very slowly, so it never had time to turn all the way into a solid. Instead, it stayed in that middle state, not fully solid, not fully liquid.

How This Affects Real Life

If you look at old windows from centuries ago, they’re usually thicker at the bottom. That’s because the glass was cooling very slowly back then, and the heavier parts sank down over time, like honey flowing really, really slowly.

Modern glass cools faster, so it doesn’t have that same effect anymore, but it's still not a solid or liquid, just something in between! Glass isn’t really a solid or a liquid, it’s kind of in between.

Imagine you have a big block of ice. If you leave it out in the sun, it slowly melts into water. That's like a solid turning into a liquid. Now imagine that same block of ice, but instead of melting all at once, it just gets slower and slower, like it’s trying to decide what it wants to be.

That's kind of what glass is like. It was once molten rock or sand, heated up really hot until it became liquid. But then it cooled down very slowly, so it never had time to turn all the way into a solid. Instead, it stayed in that middle state, not fully solid, not fully liquid.

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Examples

  1. A window that becomes slightly thicker at the bottom over centuries
  2. Old cathedral windows being uneven
  3. Glass not breaking like ice when frozen

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