Why does a glass cut deeper than a knife?

A glass can cut deeper than a knife because it has a sharp, brittle edge that can create a fine, concentrated point of pressure when it breaks. Unlike a knife, which is designed for slicing with a wider edge, glass shatters into sharp shards that can penetrate skin more easily. Additionally, the rigidity of glass allows it to maintain a sharp edge longer than many knives, increasing the potential for deeper cuts.