The glass may be strong but it is probably not "tough" in a material science sense. Metals and plastics can absorb more force and impact without fracturing whi

The glass may be strong but it is probably not "tough" in a material science sense. Metals and plastics can absorb more force and impact without fracturing which is probably what you want in a crash: http://www-materials.eng.cam.ac.uk/mpsite/properties/non-IE/toughness.html http://www-materials.eng.cam.ac.uk/mpsite/properties/non-IE/...