ELI5: Why does glass break more suddenly and completely than plastic when stressed?

r/

I was wondering why glass will shatter, breaking over a wider area than what was stressed maybe and very suddenly, appearing intact right until it isn’t. Whereas plastic slowly breaks/tears and seemingly only where you stress it.

Comments

  1. DaChieftainOfThirsk Avatar

    Glass is basically just a big sugar crystal poured into a flat mold.  When you crack a crystal it breaks along lines where the crystal isn’t perfect and the crack can travel a long distance.  Plastic is a lot more flexible though and gives way instead of cracking.