Love that story. In case anyone's curious, it's "Stationary Bike", a short story by Stephen King.

Authors don’t get paid from journals and if they do, it’s barely anything. When you pay for an article, you’re not paying the author. You’re paying the publisher. It’s largely a scam but one that is required by academia.

The river bridge that I cross every time I go to or from work is perceptibly sloped. It was the most practical way to buid that particular bridge. Building them level when possible is often easier though.

Definitely a related topic. Thanks for the tip!

Yes it makes sense if your goal is improoving the worlds knowlede and there are a lot of open knowlege platforms and open papers.

But research is expensive and scientists need to bring food to the table too. Someone needs do pay for all that and whoever pays can decide where the results go, if an aerospace industry company is researching on a new material, they do that because they hope to make proffit in the future.

Some research articles are free, and others are behind paywalls. Why? Because it costs money to operate. If you see a research paper you'd like to read that's behind a paywall, any public or university library should be able to get you a copy, because most of them have subscriptions.

Salt makes the melting point of water/snow lower.

So salt water needs to be less than 32f/0c to freeze.

You put salt on snow to melt it because cold water is less dangerous than snow.

You do the same icecream makers on the outside with ice. This is because it's better to have the colder than ice water than ice which has air pockets between the ice and the bowl

4th hint: tie a knot in it before disposing after the deed is done. It will leak and become gross.

We use it to melt ice in both cases.

Salt lowers the freezing point of water. Fresh water freezes at 0°C. With enough salt, you can lower that quite a bit. At 10% salt concentration, you're down to about -6°C, and at 20%, the water freezes at about -16°C.

So, suppose you fill a bucket with ice that is -12°C, and you add 20% salt. This lowers the freezing point to -16°C, but the ice is warmer than that, so it melts. And the action of melting actually absorbs quite a bit of energy, so this will lower the temperature. So you get a bucket full of ice water (i.e. a mixture of liquid water and chunks of ice) at a temperature of -16°C. Stick a metal bowl in there and you can make ice cream in it.

Why do you want this and not just ice? Well, solid ice cubes or shavings don't make good contact with the bowl that contains the ice cream ingredients, so the heat doesn't transfer very quickly from the bowl to the ice. Liquid water, on the other hand, makes great contact with the bowl, but normal liquid water isn't cold enough to freeze the ingredients. So the perfect combination is liquid water that is also below the freezing point of your ice cream ingredients.

Note that we added salt to make the ice in the bucket melt. This is no different from putting salt on roads to melt snow or ice.

Earth is full of craters. Some may argue half of it is a huge crater : https://www.esa.int/ESA_Multimedia/Images/2010/04/Earth_Explorers_The_Earth_s_true_shape

I know this isn't really what you asked about, but on a semi-related topic, Stuff you should know (podcast) released an episode on invasive species not too long ago. It kind of touches on some of these points. Pretty interesting.

Great answers, and I don't (didn't until now) have the biology behind it, but isn't the environment on which each species habitats a reason for it also? If we see it as a painting, birds "background" is sky (blue) andr trees (green) and colorful flowers so to camouflage they need to be colorful. Same goes for fish: sea (blue) , seaweed (greenish-yeallow), corals colorful. Also fish have this silver reflective effect to mimic sunlight in the sea. And packs of birds white belly black top, so when they Move in hundreds they look like one big bird. Also there are the octopus and other sea creatures but also chameleons that can change color. Insects that look like flowers or sticks. On the contrary, lions and tigers and pumas and other mammals live in Savannah, where the background is mainly ochre yellow from the sun and grass so that is their best camouflage option. The spots on some help with the camouflage also. Mice and castors and the rest have the ground as a "background" so dark grey or dark brown would be the best because they live under the surface. I mean, if I think about zebras, they didn't make the best choice, but at least they move in packs and it's quantity over quality. So isn't firstly the survival the evolution reason, and then the mating?

In theory yes, but fertilizer is moved around the world as food, some of that is deliberate by farmers and another part is the Eart's environmental system, including moving dust from the Bodele depression in Africa to South America. https://youtu.be/Ggeu_M7HRR4

I see why you'd ask, but I think huge amounts of fertilizer are also moved, which are not biomass until incorporated in plant growth.

Also natural ecosystems (in balance) would normalize biomass to some extent. A pond with algae can easily replace some algae that you take, because it grows to fill the pond. Thus, if you expose the surface water, you give an opportunity for replacement growth that wouldn't have existed. That biomass primarily comes from water and carbon dioxide in the air that gets converted.

A-bombs are the original nuclear bomb, and use fission of big atoms (hence "atomic bomb") to generate the explosion. These are generally much lower yield (up to a few hundred kilotons, maybe 10-20x the size of Hiroshima).

But shortly after inventing the A-bomb, scientists worked out you could generate exponentially more bang by using an A-bomb as a kind of trigger to set off fusion in Hydrogen, like what our star runs off. This is why H(ydrogen)-bombs are also known as "thermonuclear" weapons, because they use the heat generated by the triggering A-bomb to start fusion. H-bombs are way larger, the largest detonated was Tsar Bomba, 50 megatons! (50,000 kilotons). This is about 3,000 times more powerful than the Hiroshima bomb.

So in short, A-bombs are smaller and use fission of heavy elements to make the bang. H-bombs are much more powerful, and use an A-bomb "trigger" to create fusion in a hydrogen fuel source.

Yeah, of course! The nature of orbital mechanics (and I don't understand it well at all) and the frequency at which the Moon orbits the Earth means that it's likely that anything zooming in is probably going to encounter the Moon's gravity first, but it's by no means guaranteed.

Not trying to brag but since you brought it up, both my dick game and head game are good enough to the point where I'm not really concerned about ribbed condoms making a difference. A different shoe isnt gonna make or break michael jordan when he steps onto the court. Hes gonna run the match regardless. Just saying.

> I don't know if the ribbed actually make a difference for the girls

Have you tried asking? Consideration about the pleasure of your partner might be a welcome one

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"when gas burns in air, it becomes a gas" 😂

Couldn’t the same be true about earth? It’s significant gravity pulls away debris headed to the moon?

Yes, that's why we have tons of already existing semi autonomous vehicles with many more under construction as opposed to rail. Nobody ever in history has ever build rail and no one in their right mind would think to buil new lines

Maybe a bridge constructed in the 1930s had such limitations.
But modern suspension bridges often are built tall enough for ships to pass under, with ramps that get that high on either end. They don't really care if the height change on the ramp has to be small or large on one or both ends.

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