I briefly read about this to learn more. From my brief understanding, the users talking about polarising filters are not quite right. U/connor is right.

PDLCs seem to be the predominate type in planes.

While in displays, LCs are used to control polarity of light, in PDLCs they are used to control the degree of light scattering (lower voltage = more scattering = more opaque)

I've put some of those up on an office space we designed, years ago. Except it was included in the glass between two panes.

It's crazy expensive, and let me tell you, we didn't took any chances with the stuff.

The idea isn't that it is going to somehow get more rain to fall on the roof than if it was evenly sloped, which as you rightly guessed would be impossible.

Instead what the steps are intended to do is slow down the flow of the rain as it runs off the roof so that it can be caught by the gutters and stored in a tank under the house. If the roof was just a straight slope then the water would hit the gutter going quickly and some portion of it could splash over. Instead by increasing the surface area while not changing the overall slope the friction of the water flowing is increased and its speed reduced.

It’s got a LCD film in it.
When energised the crystals in it align and it becomes opaque.

The mirrors in my car have the same film and will automatically darken at night to stop any chance of getting blinded by reflected headlights.

When you know the notes to sing, you can sing most anything

There's a film applied to the window that has a layer of liquid crystals sandwiched in-between two pieces of plastic.

When the film is turned 'off' the liquid crystals can do whatever they want which creates opaqueness in the window as they're all just scattered about.

When you turn it 'on' a current of electricity is run through the film which causes all the liquid crystals to snap into alignment and become clear.

It's called PDLC film.

They're LCD screens without the reflective part. There is a polarization filter and the liquid crystal. When the polarizations are aligned it lets light through. You can control the polarization of the liquid crystal by applying a voltage. The greater the polarization mismatch the more of the light that is filtered and the darker the window.

It's the same idea to taking two polarizing filters and rotating them relative to each other. Instead of mechanically rotating one filter you adjust the molecules with an application of electricity to change the polarity.

There are polarized particles in the glass that change orientation when they receive an electrical voltage through the edge of the panel. When the voltage changes, they reorient themselves and block some of the light.

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Can confirm. I have had weeds in my yard that look like a wild marijuana plant.

Cannabis flowers (the part humans smoke) are not pollinated by pollinators

They are wind pollinated, much like corn

So the flowers are not evolved to look appealing to pollinators, like a tulip or whatever, and instead they evolved to disperse and catch windborne pollen. Which is why the marijuana 'buds' are shaped the way they are. It's the female flower that is hairy to catch the pollen from the air.

Corn also has weird flowers for similar reasons (the corn 'strings' play a similar role).

For the leaf shape... idk, no idea, but there are other species with somewhat similar leaves

And idk for sure, but there are theories the THC was acquired from bacteria. That the plant cell absorbed a bacterium similarly to the chloroplast endiosymbiosis theory, and then the bacterial DNA found its way into the plant DNA. Which is fascinating. No idea if this is resolved or not. If you don't know what I'm talking about look up the chloroplast endosymbiosis theory, it's amazing.

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It's recognizably a chicken, but it's less than half the weight of modern chickens bred for lots of meat. The females are less familiar-looking, as well.

That's true, not all. There will always be exceptions.

Not all of them though

Not all.

Very much this. Domestication changes the appearance and features of not just vegetation to suit human wants and needs. Look up any crop, animal or fruit before domestication. Most of them look nothing like what we have today, borderline inedible as well.

Other things have Cannabinoids in them, but in low doses. https://www.yahoo.com/video/cannabinoids-without-cannabis-yes-everyday-184410155.html

Weed grown indoors is where you get all the pretty pictures. The plant is grown under near perfect conditions. Temp, nutrients, watering, number of plants in a room, light, etc. So many factors that just one going down could turn your plant into one that's loaded with seeds or just stunts it's growth. Outdoor plants look more "natural" and are usually used for THC extracts. Like oils and topicals.

A lot of plants are very "unique" looking in structure and flower.

Cannabis leaves aren't actually all that unique looking. Many completely unrelated plants have similar shaped leaves. The Japanese maple is a popular one.

And yes, as far as we know, only cannabis naturally produces THC in any measurable quantity.

Wild cannabis looks much more well, weed-like than the specially bred hydroponic stuff that's all shiny and colorful. When a plant looks unusual like multi-colored corn or square watermelons, there's a good chance people had a hand in making it that way. As far as it's known, cannabis the the only natural source if THC

Very few diagrams of the solar system are strictly accurate for a reasons.

1. The relative size of the planets + the sun are just too different from each other. The sun is 285 times as wide as Mercury, the smallest of the 8 (It should be 9, I still love you Pluto) major planets.
2. The distances between them are massive and if drawn to scale would never fit on a single page while still allowing you to see all of the orbits.
3. Most diagrams are 2 dimensional representations and the planets actually orbit in 3 dimensions.

While the major planets (and many other solar system objects) orbit the sun in roughly the same disc they aren’t all doing so on the exact same plane.

Put another way of you were to look at our solar system from the “side” such at the earth stayed “flat” as it rotated around the sun, ie it never appeared to move up or down, the other planets would NOT do the same. As they orbited they would appear to go above and below the line drawn between the earth and the sun by as much as 7° in the case of Mercury. The Earth-Sun orbital plane is called the ecliptic and it’s one reference point we use when talking about orbits, because we live on Earth so it’s convenient to do so. But it’s not the ONLY reference plane you can use.

For example, you might already know that the Earth is tilted relative to its orbit around the Sun, but did you know the Sun is tilted too? I’d we drew our plane relative to the suns equator instead of the sun Earth orbit, earth would appear to move above and below this imaginary plane by more than 7°! In fact Mercury, the planet with the greatest variation relative to the Earth/Sun plane (the ecliptic) is the one that varies the least relative to the Suns equatorial plane.

There are other reference planes too. You can make one based on the orbit of any object around the sun. Or you can find the average of all the planets and weight it relative to their mass. That particular plane is the Laplace invariable plane.

So why don’t they all orbit on the same plane? Because planetary system formation is messy! Everything (well almost everything) in our solar system started out as big dust cloud. Not everything was moving in the same direction but overtime as objects collided and gravity pulled things together their average radial velocity ended up in roughly the same direction. But roughly in solar system scales leaves a bit of room for variation. Collisions over time perturbed the orbits (and rotational angles) of different planetary bodies.

Take Uranus for example. It’s spinning basically on its side (90°) relative to its orbit! That means one of its poles points roughly in the direction of the sun.

Meanwhile Venus is spinning backwards relative to the other planets, which probably means it got flipped over at one point due to one or more collisions.

And on top of all that, despite what it may look like the planets don’t orbit in perfect circles either but in ovals. Earths distance from the sun varies between 147 and 152 million km over one orbit (one year). Little Mercury varies between 48 and 70 million KM in its rapid orbit (88 earth days). And poor demoted Pluto has an even greater orbital variation over its epic 90,560 day “year” coming as close as 4.4 billion km and getting as far away as 7.4 billion km. Meaning during part of its orbit it’s actually closer than Neptune. This lasts about 20 years and the recent recent occurrence was from Feb 1979 to Feb 1999. Unfortunately you’ll have to wait for about 230 years for it to happen again, so if you were born after Feb 11, 1999 you missed it.

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To add onto that the particles that weren't traveling on the same plane would bump into each other averaging out the variation of velocities outside of the rotating disc

Now I'm hungry

This sounds like the ancient Italian myth of the creation of the universe - we're all a part of a giant pizza, our planet but a slice of pepperoni