How Do Knives Work?

The blade of a knife is like a very thin hand. ... When you try to cut a tomato, a blunt knife crushes a wide band of plant cells underneath it but a sharp knife will cut through a single line of cells, separating the long-chain cellulose molecules in the cell wall. The sharpest knives are those with the thinnest edges.

Do knives cut atoms?

A knife cannot cut anything smaller than the blade of a knife. Since knives are made out of atoms, they can't cut atoms. The splitting of atoms in atomic bombs happens as a result of a different process. ... However, even these atoms can't be cut with a knife, because the atoms are smaller than the knife is.

How do blades cut things?

The handle or back of the blade has a large area compared to the fine edge. This concentration of applied force onto the small edge area increases the pressure exerted by the edge. It is this high pressure that allows a blade to cut through a material by breaking the bonds between the molecules/crystals/fibers/etc.