SciShow is supported by Brilliant.org. [♪♩INTRO].

So you’ve just moved into your new apartment, set up the furniture, and stashed away your clothes. The only thing left to do is set up your wireless router so you can watch the latest video from your favorite science-based Youtube channel.

But where’s the best place to put it? Keeping your signal from dropping out might seem like a black art, subject to the whims of the internet gods. But science is here to help!

The main thing to keep in mind is that Wi-Fi is based on a technology much older than the internet itself: radio. At the most basic level, your router is essentially just a tiny radio broadcast station — except that it's using frequencies in the microwave range, which is a little bit higher on the electromagnetic spectrum. So, like with all sources of electromagnetic waves, the farther you get from your router’s antenna, the weaker the signal.

And it’s an exponential decrease — if you go from 1 to 2 meters away from the router, the signal is only a quarter as strong, and at 3 meters it’s only a ninth as strong. So the most obvious rule of Wi-Fi is to set up your router as close as possible to where you want to use your devices. That said, the electromagnetic frequencies used by Wi-Fi are also absorbed to some extent by things like walls, floors, and ceilings.

It’s even worse if there are a lot of water-carrying pipes in them, because water absorbs Wi-Fi waves really well. So just moving your fish tank out of the way can actually make a big difference! And here’s something people don’t always think about: we’re all basically giant bags of water.

So a crowded room full of people can also have a measurable impact on your connection — although asking them all to get out of the way so you can get back to binge watching. Stranger Things might not come off so well. Metal can also be a problem, because it’s really good at reflecting electromagnetic waves.

That’s why it’s shiny — it reflects light. That means things like an oven, a TV, or a large metal table will scatter your Wi-Fi signal, so you’re going to want to keep them from getting between you and your router, too. And then there are your neighbors.

Most Wi-Fi networks use the 2.4 gigahertz frequency, which only has a certain number of channels, or subdivided frequency ranges, to broadcast on. If yours overlaps with your neighbor’s, it’s much harder for your device to stay connected to the right signal. Newer 5 gigahertz networks have more channels available, which makes this less of a problem, but not all routers and devices can use them.

If you’ve adjusted for all of this and you’re still having issues, it might be time to buy a Wi-Fi signal booster. But before you do that, consider one final trick:. Your router’s antenna doesn’t broadcast equally in all directions.

You might think that pointing the tip of the antenna at your device will point more of the signal in that direction, but it’s actually the opposite. The antenna broadcasts most strongly in a ring outwards from the axis of the antenna, in a donut shape. So to increase the strength in a certain direction, it’s best to point your antenna perpendicular to where you want the signal to be strongest!

Keep all this in mind, and you should be able to watch as many SciShow videos in your bed as you want to. But... before you take our advice to your own apartment, you can practice arranging your routers for the best signal by taking this Brilliant.org quiz with us. So I'm just going to skip through the lesson a little bit, just to show it off.

We have to figure out which one of these rooms can't be guarded by a single guard—or a single Wi-Fi router. So in shape A, if I'm down here I can see down both of the legs of the room. Uh, and in B we have the same thing, I can see down all four legs...

Uh, but for C it looks like no matter where I set up... I can't see down this leg and this leg at the same time. So I think that's the answer.

Boom! And this is one of the cool things that I really love about Brilliant—is that they use these examples, like, guards and art galleries to teach you the concept, but then these ideas are applicable in real life like setting up your Wi-Fi router. So if you want to check it out and help support SciShow.

The first 77 people to sign up over at Brilliant.org/SciShow will get 20% off their annual premium subscription [♪♩OUTRO].