# Something about mints or something

So, in economics, we read this thing about someone who took *all* the mints from a restaurant cashier. He was subtle at first, but eventually he just shoved them all in his pocket and left. So that was pretty funny, I'd like to dare one of my friends to try it some time.

So I just finished that, and then I remembered I had to do a blog post (whoa, bye fourth wall), and it got me thinking about something I learned not to long ago. It's about napkin rings - more technically, spherical rings. I thought about them because, well, mints are toruses, as are napkin rings. That's about it.

A napkin ring is an object that's the result of taking a solid sphere, and cutting out a cylinder from the center of it, all the way through the sphere. They look like, well, napkin rings. Now, there's a pretty interesting property of napkin rings, that is *kinda* physics-y, but it's more just mathematical. Although I'm sure there's some interesting physics going along with these, maybe some cool rotational inertia properties. Anyway, the property I'm talking about has to do with the volume of the ring. You see, if you have two napkin rings that are the same height - that being measure one the same axis along which the cylindrical hole was cut - they will always have the exact same volume. Isn't that kinda cool? You could take an orange (well, a spherically perfect orange, in the shape of a perfect sphere), and the Earth (again, a spherically perfect Earth - ours is actually fairly eccentric) and you cut them into napkin rings of the same exact height, they will have the same exact volume.

Here's a video Vsauce made on the topic (I'll admit, it's not a very exciting video, it's just him going through some basic algebra, and proving this equal-volume property):

So yeah, there. Something kinda (probably not really for most people, but whatever, I think it's cool) cool about a *physic*al object. See what I did there? It's totally physics related.

Hey! The first legitimate post, on what's sure to become a pretty cringey blog. See you next week!

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