When you drop molten glass into cold water, you get a curious object: a Prince Rupert's Drop, shaped like a teardrop with a long, wiggly tail. What's so curious about the Prince Rupert's Drop is that you can hit the bulb as hard as you like with a hammer, throw it against the wall, and yet, even though we think of glass as fragile, it will not break.
That is, until you hit the sweet spot. If you damage any part of the tail, just a tiny bit, the entire drop explodes outward in a stunning display.
Although the drops have been around for centuries, the reason for this strange behavior has only been discovered recently -- and it can be seen by watching the glass explode in slow motion. That's what YouTube science educator Destin of Smarter Every Day has done. … Read more