Destin, the proprietor of YouTube channel Smarter Every Day, recently uploaded a fascinating video about the Prince Rupert Drop, a phenomenon involving molten glass that is dripped into water and allowed to cool. The rapid cooling forms a tear-drop base with a long tail, and creates some interesting internal stresses — large compressive stresses on the exterior battle with tensile stresses in the core. This makes the bulb resistant to damage, even hammer blows, as Destin shows. But so much as nick the tail of the drop, and it seems to literally explode.
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