Serrations cut better because they have high points and low points along the edge. When a serrated edge comes into contact with an object, the high points of the serrations meet the object first. This results in more pressure per area at these high points, as there is a smaller contact area compared to a straight edge.
The increased pressure on these high points allows the serration to puncture and tear the object more efficiently. Think of it like using a knife with serrations to cut through a tough piece of meat. The high points of the serrations concentrate the force and allow for easier penetration into the meat, making it easier to cut through.
The low points between the serrations also play a role in the cutting process. They act as spaces for the material being cut to go, reducing friction and preventing the blade from getting stuck. This helps to maintain a smoother cutting motion and prevents the serrated edge from getting jammed while cutting.
The combination of these high and low points on a serrated edge creates a saw-like action. This saw-like action allows the serration to grip the material being cut and tear through it more effectively. It is similar to how a saw cuts through wood, using a back-and-forth motion to make the cutting process easier.
In my personal experience, I have found that serrated edges are particularly useful when cutting through tough or fibrous materials. For example, I have used serrated knives to cut through crusty bread or thick-skinned fruits like pineapples. The serrations on the blade make it much easier to penetrate and cut through these types of materials, compared to using a straight-edged knife.
Serrations cut better because the high points on the serration concentrate the force and allow for easier penetration and tearing of the material being cut. The low points between the serrations reduce friction and prevent the blade from getting stuck. This combination of high and low points creates a saw-like action, which makes the cutting process more efficient and effective.