What happens when an edge becomes flat?


So at some point, no matter how sharp an edge or blade, at some size difference it’s essentially flat right? So what happens to the things it can’t cut because it’s flat compared to them? Been bothering me since I was 12.

In: Physics

Like trying to cut an 8.5 x 11 piece of paper in half such that if it worked you’d get two pieces of 8.5 x 11 pieces of paper, but thinner? You’d just push the edge and not cut it (of course in my example, the paper would get scrunched up; but if you had an extremely thin piece of anything the same thickness as the edge of the knife, the knife couldn’t cut it edge to edge. If the knife were really sharp, you could probably slice diagonally through the thin object through the surface plane or shave off a bit of the plane.)

Basically, at any sharpness the edge isn’t perfectly exactly separating particles. It’s spreading out what is there (cutting it/making the parts further apart). But even a razor edge is still just hitting a super small part of what it’s cutting.

Put an apple on a cutting board and cut it with a not-so-sharp knife. There will be a little bit of skin and fruit on the board and/or edge if the knife. You’re poking it really hard in a super small space. It’ll squish or move whatever it can’t cut, depending on how hard you push.

Really, you have it figured out, I think. It’s just odd to think of cutting things this way so it seems confusing. Lol