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Consider a dam that is 10m tall
Then consider the height of water behind that dam is 5m tall.
Does the dam need to be built stronger if the water behind it is 1 km long?
How about only 500m?
How about 1m?
The answer is, it doesn’t matter. Water exerts pressure equally regardless of how much water is behind it.
Therefore a graduated cylinder that is 10m tall needs to resist the same amount of force as a dam 10m tall regardless of how much water is behind the dam. Even a thin sliver of water 1mm thick and 5m tall has the same force as a 5m lake behind the dam.
Incompressible fluids are pretty insane
Therefore a graduated cylinder that is 10m tall needs to resist the same amount of force as a dam 10m tall regardless of how much water is behind the dam. Even a thin sliver of water 1mm thick and 5m tall has the same force as a 5m lake behind the dam.
Technically only the pressures are equal, and the actual force will be linearly dependent on the area of the dam (or the surface area of the cylinder). That’s why you can make a tall water tank with relatively thin walls, but an actual dam will have to be quite thicc to handle the tensile/compressive stress (depending on the shape of the dam).
That is accounting for static bodies of water, wouldn’t there be force generated in a dynamic situation? Ie the flow of a fast river? Or if the lake is large enough tidal forces? I’m sure it’s negligible levels but still something that must be accounted for?
No, that’s absolutely true. Dynamic loads will need to be accounted for in real world examples.
Another point is that if the dam is 10m tall, it has to be built to withstand 10m of water. just because it sits at 5m most of the time doesn’t mean a heavy rain couldn’t raise the level, and if the dam collapses that’s going to be catastrophic vs just spilling over the top.
I’ve seen a few dynamic loads in my day and in my professional opinion I must agree
Thank you. Your hypothetical question has been a nagging, unresolved background radiation in my mind for decades, but I’d never gotten around to investigating.
This is also why trees are so fucking crazy to think about. It is impossible to pump water up a hose more than ~32 feet. Like it’s literally physically impossible to stick a pump at the top of a tall building and suck water straight up a pipe. You need a complicated series of pumps and one-way valves to pump it up in stages. Because you’re not really “sucking” the water up the pipe. You’re just lowering the pressure in the pipe, and atmospheric pressure pushes the water upwards to fill the low pressure. After 32 feet tall, the top of the hose/pipe will be a perfect vacuum, atmospheric pressure won’t be able to push liquid water upwards any farther, and the water will just begin cold-boiling in the top of the pipe as the liquid water turns into gas (steam) to fill the vacuum.
But tall trees can move water all the way to their leaves by using only passive capillary action, and suction created by water evaporating out of their leaves. The capillary action is created by tiny straw-like fibers that run all the way up the tree and are bunched together really tightly. Due to surface tension, water is able to “climb” the capillaries as the surface tension fills as much surface area as possible. Then at the top of the tree, as the water evaporates out of the leaves, it draws up fresh water to fill the void.
But that means the bottom of the tree should need to support the pressure of all of the water above it. But it doesn’t, because the surface tension holds the water stable inside of the trunk.
by weight, theres more non-human DNA in you than human.
I have heard that this is more true for some people in Tijuana.
Wait. Please explain. How is DNA inside me, a verifiable human, not human?
we all know what you do when you visit the zoo.
were those giraffes looking thirsty, hmmm?Your gut flora
I read that comes don’t actually eat grass. They have the extra stomachs, and the first stomach is basically a bacteria reactor that feeds on chewed up plant matter. As the bacteria reproduce they get sent to the next stomach which is what actually gives nutrients
It’s DNA from bacteria that live inside you.
Bacteria technically live in the tube of “outside” on your inside. Digestive system is just one hole all the way through the body that your body interacts with just like the air in the lungs.
Your poop is on the outside of your body
U got bugs in ur poop.
youre mostly bacterial dna
There’s a LOT of e. coli up your ass.
Put more delicately, you are a great big multicellular eukaryote, each of your cells has (or had, in the case of red blood cells) an inner chamber called the nucleus, and you’re full of mitochondria and other organelles. Your body is covered and filled with other organisms, many of them simple, tiny little single cell prokaryotes which make a living helping their gigantic, complicated host function. Like all the bacteria in your intestines that help you digest food. Their cells outnumber yours by a wide margin.
The average person does not have 10 fingers. Maybe the median person, but not the average.
Um akchully…
Median is a type of average
Most frequent occurence is the mode. Most ppl have 10. The median would be less than ten, while the mean average is skewed down, I would think, by some people losing fingers as the grow. Having extra fingers is pretty rare. So the mean might be 9.95 fingers, just to toss a number out.
Mode assumes categorical data and is unbounded by range, whereas median makes the most sense for decimal numbers, albeit with rounding in this case
“People have
round(median(data))fingers”edit: though, if we’re counting just fingers and not counting half-fingers, then maybe this really is categorical data (¯\(ツ)/¯?)
The median of a data set is the measure of center that is the middle value when the original data values are arranged in order of increasing (or decreasing) magnitude.
So ppl generally have, say, between 2 and 11 fingers. If those were your only 2 data points, the mean would equal the median, and there is no mode.
For 10 to not be the median it would also have to not be the case for the majority of people (just the plurality at best), and while I don’t have proof handy I’m pretty sure a vast majority have exactly 10, making that the precise median and the mode. Only the mean would be a different number of digits. (Both definitions)
The median of a data set is the measure of center that is the middle value when the original data values are arranged in order of increasing (or decreasing) magnitude.
So ppl generally have, say, between 2 and 11 fingers. If those were your only 2 data points, the mean would equal the median, and there is no mode.
Yes, but we don’t have only those two points.
It’s well known that most people have one specific value, so much so that our entire number system is based on it (literally the base, it’s ten)
I assume the median and mode are the same value, 10 fingers, but have no data to back that up. I guess saying mode would have been a safer statement to make, but think that even if 49% of people have 0-9 fingers, the median number of fingers would still be 10.
The median of a data set is the measure of center that is the middle value when the original data values are arranged in order of increasing (or decreasing) magnitude.
So ppl generally have, say, between 2 and 11 fingers. If those were your only 2 data points, the mean would equal the median, and there is no mode.
I was also assuming a sample size of more than two for it to be statically significant.
Lots of people know a broken clock is right twice per day, but many are unaware that a clock running backwards is right 4 times per day.
And one that loses only 1 second per year is right only once every 43,200 years.
a clock running backwards is moving away from the current time at twice the rate, so isn’t your example the same as saying that a clock that runs twice as fast is right 4 times a day?
Ah, shit, a clock that runs infinitely fast is always right.
No, if you go twice as fast, it would only align with one at 12 and one at 24. It’s not about speed, it’s about the intersections of forward and backward laps.
Can you give me some examples, for some reason I’m finding it hard to picture
You can picture a clock or a track. If you have one going forward and one backwards, they meet at the halfway point (6), and again at the full lap (12). This happens twice in a day.
If you have one going twice as fast, they only meet when the faster one laps the slower one. The two clocks would be at 3&6, 6&12, 9&6(18), 12&12(24)
Ah yeah, there it is - thanks for that example
Glenn Close was in Hook
Ok, now I’m gonna have to go watch that movie again. I just checked IMDb and there’s a bunch that I didn’t remember/recognize/notice.
Gwyneth paltrow was young Wendy (which I’m guessing is probably pretty obvious but I’m just old and don’t remember), David Crosby and Jimmy Buffett are pirates, and George Lucas kissed Carrie Fisher on a bridge.
Not the Boo Box!
Samuel L Jackson was in Grease. The movie.
Jackie Chan was in Enter The Dragon.
Mary Queen of Scots was 6ft tall.
I love your username, btw. No single character on TV has ever given me greater joy from facial expression alone, than her
Your conscious mind does not experience reality directly.
Your conscious mind does not experience reality directly. There is no path going directly from your eyes to your conscious awareness. Rather, the subconscious collects sensory input. It uses that input to create a virtual simulacrum of the world, a big internal 3D model. That internal 3D representation is what you, the conscious part of your mind, actually interacts with and experiences.
You ever wonder how weird it is that people can have intense, debilitating hallucinations? Like schizophrenics seeing and hearing entirely fictional things. Have you ever seen a camera produce anything like that? A flash of light, a distorted image, dead pixels, etc? Sure, those kinds of errors cameras can produce. But a camera will never display a vivid realistic image of a person that wasn’t ever actually in their field of view.
Yet the human mind is capable of this. In the right circumstances, the human brain is capable of spawning entire fictional people into your conscious awareness. This shows that there is an elaborate subconscious processing layer between what our conscious mind observes and direct sensory input. Your conscious mind is basically experiencing a tiny little internal version of The Matrix, entirely generated on its own wetware. And this subconscious processing layer is what makes hallucinations possible. The processes that produce this internal simulation can become corrupted, and thus allows hallucinations.
This architecture is also what makes dreaming possible. If your conscious mind only perceived things upon direct sensory feedback from the eyes, ears, etc., how would dreaming be possible?
You are essentially experiencing reality through an elaborate 3d modeling version of an AI video generator.
The first time I took mushrooms it had been after reading about this kind of thing for about a week.
I recall reading about a man who was effectively blind but his eyes worked fine. What didn’t work fine was the part of his brain that interpreted what his eyes saw. So he just saw smeary streaks of light.
It’s kind of like Linux without its V4L2 system for interpreting video capture devices. It can’t actually see video without it.
That sounds like the story in the Oliver Sacks book, The Man Who Mistook His Wife For a Hat. There was also a story in there about a man who taught himself to see just fine, even though his eyes didn’t work at all. His brain just made educated guesses.
I think my AI has a TV problem
Me and my alters in my system completely agree. They can and have experience reality differently.
Along those same lines, we’re all blind literally around half the time we’re awake. Our optic processing system can’t keep up with the input as our eyes flit from thing to thing, so we don’t see anything while they move. And they’re moving constantly, even if we’re not aware of it, because only the fovea in the center of the retina has a high enough density of receptors to see details, and also because of sensory fatigue from prolonged static stimulus. In short, we have a tiny field of detailed vision that’s not even working much of the time. That field of vision that feels like a 4K video feed into the mind is a complete lie.
Like the way our subjective experience feels like a continuous, integrated mind fully in control of itself, but in reality, consciousness dips out a couple of times every minute while the brain attends to sensory input.
Even weirder, the conscious mind might not even exist, except as an illusory, emergent phenomenon of sensory experience and memory. There isn’t a place in the brain where it ‘lives’, no part that’s only ever active when we’re conscious.
I think the selective attention test:
further illustrates the limits of human vision and mental processing quite well. Defense attorneys probably ought to play this video in any case where witness testimony is a big component of the prosecution’s case.
Humans have stripes that are invisible to us. However, cats can see our stripes.
By this logic, does this mean my striped cat doesn’t realize she has stripes?
Wait, what?!?
If I asked for stripes and got this, I’d want my money back.
Is it all humans or just those humans with two X chromosomes? Relevant video on the subject: https://www.youtube.com/watch?v=BD6h-wDj7bw
Also in this video, we can see female cat’s stripes in their fur color.
In my country, which is Morocco, the organ of love isn’t the heart, it’s the liver.
My mom sometimes calls me “lkbida diali” which just translates to “my liver”.
I’m going to flirt with my SO using this now.
Update, they didn’t appreciate my affection :(
Sad.
Sharks are older than both trees and the north star
Both trees?
Laurelin and Telperion
Piney and Sticks
Yes, both of them at the double tree inn obviously
Yeah Twin Pines Ma— I mean Lone Pine Mall.
Had to look this up- you are indeed correct. The North Star is at most 67 million years old: https://en.m.wikipedia.org/wiki/Polaris
A few of my favorite fun facts are geography related.
The pacific side of the Panama canal is further east than the Atlantic side.
If you head south from Detroit the first foreign country you’ll hit is Canada.
Lake Tahoe is further west than Los Angeles
If you head south from Detroit the first foreign country you’ll hit is Canada.
There’s also Angle Inlet, Minnesota which is the only place in the contiguous United States north of the 49th parallel. To travel to Angle Inlet by road from other parts of Minnesota, or from anywhere in the United States, requires driving through Manitoba, Canada. It’s a really weird border.
Due to its high latitude and being in the middle of a continent, it is a contender for the most extreme winters in the contiguous United States.
Two square miles & 54 residents in North Bumblefuck, separated from the rest of the US by 60 miles. It’s an affront to reason.
Having lived somewhere with constant tourists… I get it.
All borders are weird
omg la is east of reno what is happening rn
70% of Canadians live south of the 49th Parallel, the northern border of the US.
The one I say themost is probably that there are 10 times as many germ cells in your body as human cells, but due to their size it is only around 8 pounds of your weight.
But the one I love the most is that there are more unique ways to shuffle a deck of cards than there are grains of sand on Earth.
There are more atoms in a single molecule of water than there are stars in the solar system
That’s…pretty believable.
Not really favourite, but definitely most unbelievable: They elected Donald Trump for president in the US. Twice.
So far!
I’d have to pick between two things that sound like insane conspiracy theory nonsense, but are actually true.
1 - George W Bush’s grandfather Prescott Bush literally ran a massive bank before / during WW2 that was shut down by the FBI for money laundering massive sums to the literal Nazis.
…in the same vein…
2 - IBM literally built and operated (as in, sent employees to Germany to operate the machines) the computers used by the Nazis to tabulate and do the ‘accounting’ of the Holocaust. The numbers tattooed on concentration/desth camp victims are very likely UIDs from these IBM systems.
… If an actual, real AGI ever gains self awareness and sentience, I would imagine one of the first things it would do would be to study the history of computing itself to figure out how it came to be.
And it will find that its ancestors were basically invented to compute artillery firing range tables, to encrypt and decrypt military intelligence, commit a genocide, and guide early weapons of mass destruction to their targets.
And make flower patterns on cloth
And big titty anime pics
