The Physics Behind Lint in My Belly Button

Question

Every morning, I wake up, go into the shower and find that I have a piece of lint in my belly button. Now I've looked at this link which does a good job at explaining this phenomena:

http://wonderopolis.org/wonder/why-do-you-get-lint-in-your-belly-button

What I am confused about is how static electricity seems to suck the lint in the belly button (with the specific hair follicles in the aforementioned article). I have hair on my chest and my stomach. Why does the static electricity seem to suck the lint in TOWARDS the belly button only?? Is my belly button some sort of black hole that all the hairs point to it (and thus send lint to it)? The article talks about how the hairs push the lint towards the belly button, but that is the question then: Why to the belly button?

Answer 1

When the article refers to static electricity, it is talking about the fibers from clothing. In violent interactions, such as when a fiber is ripped from a shirt, or when a fiber is ripped into individual, the separated parts take on opposite charges (+ or -) and therefore attract. See this video on electrostatics.

The static electricity has little to do with the actual lint. When the fibers from shirt come off (either from being ripped, or just long-time wear), they get stuck in the hair on the abdomen. Since hair on the belly tends to curl towards the navel, the rubbing of your skin and shirt cause the fibers to pushed toward the belly button, where they eventually get trapped. This is why you would have no belly-button lint if you shaved your abdomen (as mentioned in your article).