Hi, I'm Cody Gough.

And I'm Ashley Hamer.

We've got three stories from Curiosity.com to help you get smarter in just a few minutes.

Today we'll talk about how laundry machines actually clean your clothes.

A book Bill Gates thinks everyone should read, and the reason you judge other people more

harshly than you judge yourself.

Let's satisfy some curiosity.

So Cody, do you really know how your clothes get clean? I put them in the

washing machine and then it magically cleans them? Yeah, that's pretty much how most of us

understand it. I mean they get dirty, they own the washing machine, detergentgent does its magic and then your clothes come out fresh and clean.

But dirt can get really tiny.

So what about the tiny wedged in dirt particles that the detergent can't actually reach because those exist how do those

get out I guess I don't really know how detergent gets dirt at any level let alone

that small so how does that even work. Researchers actually didn't know this either, which is kind of strange. You'd think that they'd understand most of this stuff by now. They call this problem with the wedged in dirt particles the stagnant core mystery.

So this is the thing, is that detergents contain a thing called a surfactant or surface active

agent.

This reduces the surface tension of a liquid and it helps water wash away particles

of oil and grease, which are usually water repellent. It's just like what you'd use on your

dishes, right? Soapy water can get between the threads in a t-shirt, but it's less effective at getting in between the tiny fibers that make up each thread.

So if there are miniscule particles of dirt between those fibers, there is no way that detergent and water should be able to

pull them out, but they do anyway.

All right, so how do they do it?

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