Why is it hard to cut something from the outside, but if you punch a hole it’s suddenly much easier?



Let’s say I take a tube. If I try to cut with a knife, it just wont work. However if I take the tip and cut a hole, I can then suddenly cut with the knife the entire thing.

In: Physics

You’re taking the same force that was once low pressure on a large area, and turning it into high pressure on a low area. That gets you into the tube. Then, you already have a material failure, and things hold together better when there’s no failure points.

You tearing the fibers, weakening all the ones around them allowing for cuts to form more easily all cuts are are really small tears across a larger area. If you can start somewhere there is already a year the rest will follow suit. Think of it how if there is a crack in the wood you’re trying to split, you’d want to follow the crack for the least amount of effort. Or if once you crack glass, it’s more likely to not only crack again but almost always along the crack already made.