Why does stuff smash apart or break when you slam it up against something else?

Question

If i take pieces of glass and smash them together why do the break? What physical takes place physics wise?

Answer 1

I "think" it is because the resulting impact puts stress on the substance breaking the bonding force. Sometimes i believe the vibrations caused by impact will cause the breakage resulting in a time delay (split second) while the vibrations cause the before said. Best guess

Answer 2

you are putting energy into the glass by moving it.  When they smash together, there is nowhere for the energy to go except for out.  This means that it has to go outwards to release the energy and this amount of energy is strong enough to break the bond between the molecules.