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|---|---|---|---|
brdak0
|
Regarding imports and exports and their impact on nation’s economy.
|
Import = you buy stuff
Export = you sell stuff you produce
Less import = less buying
More export = more selling
|
7104b634-af50-43eb-b40b-8ececd1bcc3d
|
brdge1
|
How does capillary action pulling a fluid up a narrow tube result in a more stable state than if the fluid stayed at the same level?
|
Molecules are made of highly electrically charged particles and all interact with each other like little magnets. Some are attracted to each other, some strongly repel, and some are indifferent and neutral.
When a liquid is climbing up the inside of a narrow tube, that's an indication that the liquid molecules are more attracted to the tube wall molecules than they are to eachother. They're quite literally climbing all over eachother trying to touch the wall as that's the more optimal energy state.
But! As the liquid column grows, so too does the force of gravity. The low energy bonus the molecules are getting by touching the tube is eventually offset by the sheer weight of the column and it can climb no higher.
Climbing up the tube is increasing the surface area of the liquid, which typically means an increase in system entropy.
|
ddafaa94-a13a-4d8f-9fa3-dacc1a238752
|
brdrzf
|
How can an 2D animated movies or shows have multiple animators whilst maintaining a consistent art style?
|
Professional animators are a talented bunch - they can draw in just about any style they'd like. For their own work, they may choose a unique style, but when they are part of a team, they'll work within the parameters set by the lead animator. It's much the same way a good studio musician can play a vareity of genres well, even though they prefer one particular style when performing original compositions. Talented and trained people can do amazing things.
|
478ba35a-9e05-4aaf-a960-68fc8f689af9
|
bre3co
|
Why does using a chip credit card at the pump take so much less time than using one in the store?
|
Transactions at self serve pumps are often offline, so the card will say this person is good for certain amount of money. After you've filled up, the transaction is sent to your bank and taken from your account. Transactions in the store are often online, so a request is sent over the internet to your bank to check if you have available funds. Online transactions have to go through various networks and be processed by software so it takes longer.
Source: I implemented a debit card system for a bank.
|
5407458e-3c79-4e76-b2c3-f48e4095031f
|
bre3eh
|
Precious gems that go in jewelry have to be harder than a 7 on the Mohs scale due to quartz being the hardest airborne mineral and would scratch them, so does that mean we breathe in quartz on the daily and our lungs don't mind?
|
Quartz is made of silica, and crystalline silica [is really bad for people to breathe](_URL_0_) _if breathed in high enough amounts_ (that means high concentrations and for a long time each shift, specifically) . You’re unlikely to encounter truly dangerous amounts of airborne crystalline silica outside of an industrial setting, and even then the hazards are known and understood. Any legitimate place that uses crystalline-silica containing materials will have protection mechanisms for their workers.
To sum up: crystalline silica is bad for you, and your lungs certainly _do_ mind, but it’s likely not a big deal.
|
a06f03aa-3068-49f5-b550-f4c159e0a79e
|
bre4wd
|
What specifically happens when a military aircraft intercepts another? How is the decision made to intercept, which maneuvers and communications take place between the two, and what generally happens after?
|
There are dozens of factors to consider. If a military aircraft intercepts another it's because the other aircraft is doing something it probably shouldn't be doing (flying in airspace it's not supposed to, approaching an area it shouldn't be and ignoring orders to alter course, etc). Communication generally happens between the pilots at advice from ground personnel. Ground personnel can hear comms to and from the other aircraft and advise the pilot on how to respond (such as giving the pilot a heading to tell the other aircraft to turn towards as a sign of compliance, etc). If the other aircraft is acting in a non-compliant potentially hostile way (such as flying an intercept course with the aircraft trying to contact them) and they are ignoring any requests to show compliance (such as changing heading/standing down/etc) then the pilot may be given authority to go weapons hot and defend itself if non-compliance continues.
Generally speaking, aircraft are given parameters in which they are allowed to fly, acting outside of those parameters can be taken as non-compliance with previously agreed upon instructions. Continued non-compliance (the pilots talking to each other while their ground crews listen/advise) can lead to escalation, interception, and, if necessary, hostile action.
|
71fa9c1a-00ba-4c51-b107-a2f5f19f8f66
|
bre88j
|
How are random numbers generated by a computer?
|
Usually they are generated in a psuedorandom way, in that they are not actually random and can be calculated/predicted given the same input. However, this is good enough for most common usages of randomness.
This is done by using an algorithm to create the "random" number, and a seed value used as the input to that algorithm.
Using the same algorithm and seed will always result in the same "random" number. Most computers use something that changes often (like the current time, often down to milliseconds) as the seed value so the seed changes quickly (in the case of generating lots of "random" numbers) and won't be repeated. This doesn't mean you will never get the same random number, just that you won't be able to predict the random number because the seed won't be repeated.
Something like Minecraft that lets you supply the seed can generate the same "random" map for everyone who uses a specific seed because it follows the same algorithm.
|
29f1c6f4-6850-4547-af31-13bb8350f5cb
|
breegk
|
What is the physical discomfort in your chest, that accompanies severe anxiety, caused by?
|
When you get anxious, your heart rate goes up. It is done by the primal parts of our brain which make your heart pump more blood and supply your brain and your muscle with blood (fight or flight). You are anxious, so fast heart rate change feels as discomfort. It could also manifest itself as a feeling of pressure in your chest
|
64d3acc4-cbca-40d1-9511-e272619dffca
|
breouk
|
How does tech keep time when shut off?
|
Generally there will be a special little battery on your main board to do that, at least that's what a computer does. On your phone, if you unplug your main battery, and then turn it on (without WiFi or Cellular so it can't get the time from the internet) will it have the correct time? If so, it has a clock battery. If not, it's just using your regular battery.
|
de5ca0bf-9693-4876-9e52-9266b3616c5e
|
bretmj
|
What causes some toilet bowls to have a nearly explosive flush while others are much more “peaceful”?
|
Depends on the mechanism, but the simpler/traditional methods just have the water fall from the tank to the bowl. Many newer ones (especially meant for commercial) have a pressurized tank, that is the tank is actually a balloon and the water is pushed into the tank at line pressure (usually 40psi or so), when you flush it can then release the water at line pressure (40psi) which forces it though the toilet.
Commercial public restroom types (without a tank), skip the tank entirely and just connect the water line straight to the toilet which has the same effect (but requires a very large water line to supply the flow rates).
|
554b9963-6f8a-4a8f-a753-2a9a33d4e44a
|
brexk1
|
How are really tall buildings able to withstand high winds?
|
Most skyscrapers are built with a series of counterweights in them to help from swaying too much. The buildings are also to designed to sway in the wind. It actually makes them safer.
Imagine a stick that has been dried out. It’s very rigid, but it can be snapped easily. Then take a stick freshly cut from a tree. It can bend quite a bit before it actually breaks. That pliability works the same in the buildings.
Then think about the tall buildings in places like San Francisco and Miami. These buildings can take beatings from massive earthquakes and hurricanes and still stand strong. Windy City wind doesn’t compare to hurricane force winds. So you shouldn’t be concerned at all.
|
bb7f146d-4b67-4f73-ae54-61673724e536
|
brf4o3
|
Do we lose metal forever when it rusts?
|
Most rusting is from the pure metal becoming oxidized, meaning oxygen from the atmosphere attaches to it and changes it's chemical properties. Rust can be melted back into metal easily enough, though if a piece of metal rusts into a powder, collecting it all back becomes a challenge. When melting it back, you'll have impurities that got trapped and will need to remove them to get pure iron back.
|
49be4cba-a429-49ad-86f1-fdd72b3fa6d6
|
brf6wo
|
Why do Uber/Lyft drivers stay with the platform when they are so unhappy
|
> If I'm not happy with my employer (I work as an independent contractor), I would simply look for other work.
You make it sound so simple. The chances are that if a bunch of people are staying with jobs they're not happy with, it's because there are a shortage of better jobs.
This is a particular problem with services like Uber & Lyft, which tend towards being effective monopolies (or monopsonies, technically). Don't like being a driver for Uber? Then your options are... Lyft. Conditions for Lyft bad? Then maybe you can get work with, um, Uber.
|
f3bc3128-fd1a-4f7d-9d31-9dd2ff9a1ce6
|
brfrru
|
When taking a bath why does hot water after a while doesn't burn or it feels like getting cold?
|
because the thermal energy from the water rises and is lost in the air, leaving the water and allowing it to cool due to a loss of heat energy. and yes your body begins to get used to the pain
|
a8be7c19-0106-4ebc-8bd5-233173178ff0
|
brfxdb
|
How do animals identify what is food and what is not?
|
> But even artificial food made by humans like pet food is eaten fairly quickly by an animal that has never seen it before
Hmmm not so true for all animals. I don't know for others but rats in lab have a huge neophobia, like they fear everything new, including the food we give them.
In order for them to realise that it's food and that it can be eaten, you have to litteraly put them on food restriction so they are "starved" and start eating the food. They are really headstrong.
As for how does animals know what is food what is not ? I can't really answer you but I can tell you that rodents are very good at discriminating "bad" food from "good" food. They associate good food with salty/sugary aliments and bad food with acid/bitter ones, if they taste something bitter, they will (unless they don't have the choice) avoid the bitter food.
And rats have a very good memory for bad food experience. Let's say a rat got a sick stomach from food A. Well if you put the rat in a room with food A, the rats will not eat it. And that works up to a year after a bad food experience.
|
39aa9d0e-ee39-4b62-86c9-e4b287c1227b
|
brg6wi
|
In the United States is every last digital dollar backed up by a paper noted currency?
|
No, very little U.S. currency is actually backed by paper notes. Something like 10%. [According to this](_URL_0_), there is about $10 trillion in wealth held in cash or cash equivalents, but money supply is about $980B
|
36f55a77-1b64-48cf-8972-c24ffa7f879b
|
brgbhy
|
How do power lines work?
|
Three or 4 wires power lines are 3 phase transmission lines.
There is also a thick line that runs under the 3 ones that carry low voltage data like telephone or cable tv.
|
deb94e84-5324-438e-8a52-489ae4600e03
|
brgjr8
|
What is the source for gravity, or what causes it in things? I understand that way massive the object is, the force will be great (and depends on length between a second object too), then, the object creates it? How?
|
TLDR: We aren't entirely sure yet
Gravity is one of the fundamental forces of nature, but unlike the other forces like electromagnetism, the strong force, and the weak force, Gravity doesn't have an opposite (that we are aware of) that cancels it out. It is also the weakest of the forces by far but also seems to accumulate without limit.
What we perceive as Gravity is a warping of the fabric of spacetime and appears to be directly linked to mass. Objects do not fall towards a massive object because there is some kind of particle or force pulling on it, but rather because spacetime itself has become warped so objects fall towards each other like a ball rolling down a hill.
One current theory is that mass, and by extension gravity, is imparted onto things by the presence of sub atomic particles. This might be the Higgs Boson, or a theoretical particle called a Graviton.
It wouldn't be gravitons flying out and pulling on an object that causes gravity, but rather the presence of gravitons warps or bends space
|
cb54d192-4f98-420d-b65f-e00aac688cae
|
brgk1r
|
Why do sun burns hurt when touched and not when they happend?
|
The painful symptoms of sunburn - inflamed sensitive skin - aren't the product of the sun damage itself, but rather of your body's system immune system response to the sun damage.
The initial damage is molecular damage to your DNA. It takes some time for your body to notice the damage and for your immune system to mount a full response.
|
5e55f5ee-1ce7-42ab-9b6a-646b0e08e59b
|
brgmkm
|
How does traffic get backed up for miles barely moving and then suddenly pick up to normal highway speed?
|
It maybe a case of a traffic wave propagating through the cars. Whatever originally caused the cars to slow down is so far up ahead and so long gone that it just seems like everyone slowed down for no reason.
|
7beb25b2-87a5-423d-ae0e-a1ac1fdca853
|
brgmov
|
Why does it take a few minutes for your eyes to adjust to darkness?
|
[Rhodopsin](_URL_0_) is a protein photopigment used by the rod cells of the retina to detect gray-scale brightness and contrast, and is the key to adaptive night vision. Intense light causes the protein to decompose reducing its sensitivity in bright light (when we rely more heavily on our color-sensing cone cells anyway). Darkness allows the protein to regenerate in a process called “dark adaptation”, allowing the eye to see in low light conditions, but with reduced color discernment.
This process allows us to be able to see fairly effectively in both bright and dim light, but it takes time for our vision to adjust to sudden shifts in brightness in either direction.
|
3980b28f-384c-46bb-a4d8-0fbece7939d6
|
brgvk0
|
Why isn't our body fit and with muscled by default?
|
The really short answer is that fat is more beneficial to have than muscle when you're a nomadic hunter/gatherer and your next meal could be days away. Fat stores calories for later, muscles require more calories to maintain. So your body very very reluctantly builds up more muscle tissue than you had before, and once it does if you stop using it, it takes material to be used elsewhere.
|
da627b05-c942-40a3-9cd1-701fc1d9353a
|
brgyr4
|
Why can’t a type of plastic be invented that is biodegradable?
|
They have actually. Using hemp and other plant based fibers they can make biodegradable plastics. They are much more expensive and time consuming to produce though.
|
8caae165-03ce-4337-8a1b-80f844d68b73
|
brh2rp
|
Why does radiation cause AND kill cancer?
|
Ionizing radiation can damage DNA in your body’s cells. This damage can cause the cells to malfunction and reproduce uncontrollably, which is cancer. Focused radiation can cause so much damage to the cancers cells that they not only malfunction, but it can dry them completely killing it.
|
0ec63cc6-6b07-41f6-82df-5be9a456eb80
|
brhi5g
|
Why did Uber’s IPO fail so badly?
|
In short, Uber has never shown a profit, and people (including money people) are well aware of that.
Ad to that limp revenue growth, and Uber stock is less than appealing.
|
6ddc7b49-2b98-4e6b-9fdc-80c906ea3699
|
bri5co
|
Why aren't foreign radio channels region-locked like their tv counterparts?
|
Just try to catch electromagnetic waves from crossing the border with a net.
Technically with digital radio it could be possible, but overall it would be a huge, expensive hassle on both provider and consumer end (and likely easily bypassable anyway) just to block a 20-40km band along the border from listening to your radio.
|
63c3c0f6-0de8-4cde-9fcb-3b9486e58802
|
bri8lq
|
When birds fly together in large groups, how do they all know which direction to turn in unison?
|
They don't.
Birds' movement in large flocks is actually something talked about in a series of mathematical principles called Chaos Theory. The idea is that you can make things *appear* orderly even when they are in chaos (like having 20k birds all independently flying in a group.)
Instead of one big piece of organization, the birds all use a simple set of rules to follow: if the bird in front of me moves left, also move left. If the birds to my side change direction, also change direction. Is there a predator? If so, stay in the flock.
Using a series of simple rules like this, you get a lot of "order" out of the chaos. It's the same for schools of fish, or herds of elk.
|
094e150d-87f2-4410-838d-863140258e72
|
bri94z
|
Despite their similarities in size and population, why are Texas and California polar opposites in terms of economic prosperity?
|
Clarifying question: What makes you think they're polar opposites in terms of economic prosperity? US News' ranking of the States' economies has California at #4 and Texas at #15. That's hardly polar opposites.
|
beba702a-b388-47de-9e37-6e137344768e
|
brigfu
|
What makes the Video Player applications different? What is the difference between VLC, QuickTimePlayer and others
|
Different interface which gives you different looks/locations of buttons.
Different tools (one may give you hotkeys to skip forward/back 1,5,10,30 seconds, slow down the speed, etc.)
There are multiple formats for videos, one may not play all of them.
Some are free, some aren't. Some have open source code (so you can edit it to your liking if you're savvy) some don't.
Some have a more responsive development team and identify/patch bugs in a more timely manner.
|
4038e972-ac32-4942-a222-902c4689d899
|
briia3
|
Why do clouds sometimes form with a straight line?
|
That happens when you have air streams going up or down at that line. Usually a warm city street or a cold river is responsible.
|
66f15d41-74b3-4645-a320-dca9904406e6
|
brin65
|
why do some electrical devices call themselves dust proof and what can dust do to non-dust proof devices?
|
Dust proof usually means sealed and enough volume inside the case to release heat. Dust in non dust proof devices can jam up fans causing them to overheat or jam up any moving parts.
|
e2a00d29-3068-43f7-b739-da01226bdee5
|
brivz4
|
What are the pros and cons of "semi-EU countries"?
|
Norwegian economist here.
We have free movement of workers and capital, but not on goods.
Norway is not inside the single market. We have a hard border with Sweden and Finland, and EU implement tariffs on many of our products.
Our solution is actually horrible, but companies have had many years to adapt, so they don't feel it.
Whole industries left Norway for Sweden when Sweden became an EU member and Norway just got this EEA agreement, but almost no one remember this. So the negative impact is lost on people; they don't understand it. And you don't miss factories that left 23 years ago.
I would not recommend the EEA solution to anyone.
|
4d213733-3716-4f4d-809b-42320a5801ac
|
briyy7
|
How do ticket sales work for sports playoffs with multiple games per round, when a game that is supposed to take place in two days may not happen?
|
They are refundable. My stepdad gets season tickets every year and it includes playoffs tickets. So he gets a refund for any playoff games that don't happen.
|
6c0c14af-8c96-42f7-8863-092adf6edce4
|
brj4dy
|
How do all servers across the world ensure unique IP addresses?
|
Others have done a good job covering the basics, so I'll go into more of the technical details.
The right to use Public IPs is assigned to companies and groups by organizations like ARIN (North America) and RIPE (Europe).
Qualifying organizations (Large companies and ISPs) apply for and pay a fee to use IP address space and are assigned blocks of unique IP addresses that they are free to use as they see fit. This address space is advertised to the rest of the internet using BGP (Border Gateway Protocol) which tells the internet where those IPs are located and how to get there.
If you attempt to advertise IP space that doesn't belong to you (effectively stealing IPs) your peering partners (who your WAN network is connected to) will soon recognize that and filter out (block) the advertisements effectively dropping your network off the face of the internet until you fix it. This can cause serious havoc to the internet and is taken very seriously.
However the vast majority of organizations and private individuals are too small to warrant having blocks of IPs dedicated to them (the smallest issueable blocks are 256 IPs, while most companies only need 1 or 2). So instead it's more practical for most companies and persons to effectively lease IP addresses from larger organizations (ISPs).
When you make a connection via an ISP they lease you a temporary unique IP address which is assigned to your modem. In the case of businesses (for an additional fee) a static or permanent unchanging address(es) can be assigned to the service. These addresses are unique and unchanging and therefore better suited for hosting websites and the like.
|
81d38897-7077-464f-88b5-010a18564956
|
brj5e7
|
Why is it so difficult to suppress a cough?
|
Because it’s your bodies way of clearing your air pipe, you kinda need that thing clear so you can breathe
|
3d4ee607-1894-4dbb-931e-87e2881bc5b1
|
brj883
|
What do people mean when they say a food isn’t a “complete” protein? I.e. quinoa
|
ln order for a food to be a “complete” protein it has to have the 9 essential amino acids (lysine, leucine, etc.). Complete proteins are just types of proteins that contain the necessary levels. Quinoa would actually be considered a complete protein. You don’t have to necessarily eat meat to get complete proteins you can consume dairy and/or tofu.
|
2a09cd44-7839-4ce5-bc1b-2132b48b1e39
|
brjgjk
|
In tv shows and movies, why do really giant people/creatures always move so slow?
|
I think it just appears as if they are moving slow, but are actually covering a lot of ground.
We could use stride/steps as an example. Let's say that a stride is the distance between two planted feet after having stepped forward onto one foot while walking. Let's then assume that it would take six steps for a human to walk the distance of a giant's single stride (obviously this varies according to giant's/human's size). So with one swing of the giant's leg, it has actually moved pretty far compared to the human.
A giant's limbs are also heavier and therefore perhaps not as nimble. It takes a lot more energy for the giant to lift and lower it's feet as it walks. You could simulate this by walking around with 10lb ankle weights on. But if you had super long legs like a giant, you would still cover more ground in less time than a human while walking just because you have a much longer stride.
|
7a554b86-b8dd-4e24-8c6a-e412540c220b
|
brjhmh
|
How come if the same sound file is layered and played simultaneously you are able to depict different sound layers?
|
Without more info, I can only guess that they're not actually exactly simultaneous.
If that's the case, the original waveform and its copy combine into a new waveform with a new pattern of peaks and troughs, interpreted by our ears as different timbres (textures) and sometimes even pitches (due to new frequencies being formed), though the overall fundamental frequencies will remain about the same. This is because you're adding the value of the two waveforms' deviation from the center at every point in time, and if they're not completely even in time, sometimes one copy of the wave will be going down when the other is going up, meaning you might actually lose total deviation from zero at a given point in time when compared to the single original wave at the same moment.
Essentially, if the start times are close enough, the combination of two copies of a sound will sound like one sound that's similar to the original, but with different timbres. However, if they're far enough apart in time, your brain can separate them into two different information streams and it sounds more like an echo. Only if they are exactly simultaneous will they combine perfectly and act like a louder version of the original sound wave.
|
2bb0c95f-a0c0-4bc4-97ea-86374f051781
|
brjix3
|
is it really ONLY calories in, calories out (caloric deficit/surplus) that determines weight gain/loss? Or hormones can overpower this?
|
No amount of hormones can break the law of conservation of energy. If you are using more calories than you are eating you *will* lose weight. End of story.
What hormones can do is mess with your appetite so you are abnormally hungry or it might slow down your metabolism. Or the opposite, as you mentioned.
|
d4b3616a-a464-49f7-bc7a-3e8bcde194b1
|
brjp9q
|
what exactly is being “improved” when we see games graphically improving with time?
|
Generally speaking
- increases in texture resolution, Instead of using a 100x100 pixel texture you use one thats 500x500 now your model is less blurry, has more detail
- Increases in polygon count, more polygons allows more detailed features. go back to N64/PS1 and most characters didn't have distinct fingers due to keeping poly count lower. now you might have a few dozen polys just for a buckle on their uniform.
- New lighting techniques, dynamic shadows, HDR bloom effects etc
- New shaders and rendering techniques, from Depth of field to bump mapping, reflections etc.
Sometimes it's new tech that's more effective at rendering more realistic effects other times it's old tech it just takes more processing power to run. with improvements on the same platform it might be the latter but there's optimization other places to make up for it.
|
b2b7b577-7bb9-4877-a5eb-4723e4666666
|
brjqyn
|
how do tuning forks stay in tune, and can they ever go out of tune?
|
Tuning forks are meant to be struck on a certain type of material which is like a hard rubber in the form of a small block or mallet. If you strike it on something else you risk deforming it and changing its pitch.
that’s what I was told in choir.
|
423397fe-f9b3-48e4-9144-e04410b56c7b
|
brkhqb
|
How do cameras capture nuclear tests so vividly without succumbing to damage from the blast?
|
The camera sits in a bunker and is aimed at a periscope type setup with mirrors to film the test. [Special high speed cameras](_URL_0_) use a fast moving mirror to capture incredibly high frame rate footage of the blasts.
|
ecca0f12-d018-43f6-a8f6-c34a4d4fa647
|
brkl6z
|
why do ancient battle result in so little casualties from losing side and they concede?
|
Historically, armies would often break once they lost 5-10% of their fighting force. Nobody wanted to die and morale was fragile. All it took was the death of a leader or a perceived disadvantage and the entire army would disintegrate into a mob of fleeing men.
Well-disciplined armies could withstand greater losses, but very rarely would an entire army stand fighting until they were destroyed. They were after all humans, not combat-oriented machines.
Anyway keeping enemy combatants alive might be useful for ransoms, or you might even be able to turn them into your service if you bribed their leaders. There was also ritual sacrifices such as in Rome which required captured nobles.
|
05cb2e16-c097-4a08-887c-0a7cc9194282
|
brkwd0
|
Why do songs with only instruments have song titles as if they had lyrics?
|
A lot of it is the "feel" of a song. Music can evoke a lot of emotions without lyrics, in fact, most of the emotional impact from a song comes from the music.
& #x200B;
In fact, to that immediate song, Herbie wrote it while remembering a watermelon salesman that would roam his home streets of Chicago, and the beat is meant to resemble that of his wagon wheels on cobblestone.
& #x200B;
[_URL_0_](_URL_0_)
|
18e5f80c-529a-48b5-8dcc-017ea98dde62
|
brl7qj
|
Why do some animals come out of the womb walking/swimming?
|
They’re able to develop further in the womb.
Humans brains growing (probably after discovering fire and being able to cook and eat meat) caused the head to grow as well which made child birth have to happen faster than it normally would. This is why human babies are so useless (aka can’t crawl or anything) for months after they are born.
|
ed1ecb3e-b43f-4683-9a95-b8958ab2dc20
|
brlco3
|
Why does the skin on chapped and dry lips stick your lips together? (As in when you close your mouth)
|
I always assumed that it was the saliva drying, acting as a kind of glue, but I may be wrong.
|
b66384c4-7e14-44a1-8dc5-f5a982091982
|
brlk6f
|
Could the world eventually become one race through the interbreeding of races over time?
|
Yes. Technically we are already one race. The biological differences between what we refer to as "races" are so minor and negligible that there is no scientific basis for differentiating them. That's what people mean when they say that "race" is a cultural construct.
But when it comes to those minor biological differences, like skin tone, even they will blend together with time, assuming enough interbreeding happens. There is actually already a sort of prototype for this: [Brazil](_URL_0_). Almost half of Brazil's population is a mix between European, African, and Amerindian ancestry.
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f7f2c535-7f7a-4a31-bc4e-0a1ad3839089
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brlr7g
|
Looking for an in depth explanation of stocks and their market starting from the basics all the way to the complex.
|
Sorry, didn't realise the sub. My link to [investopia](_URL_0_) was removed.
A "stock" or a "share" (they're the same thing) is owning a slice of a company. Big companies are spilt into many millions of separate shares, but it varies company to company.
Say your friend wants to set up a lemonade stand. They need $10 to buy the essentials (lemonade, cups and table) but they only have $5. So they come to you and ask if you'd like to start a "business". You'd both put $5 towards it, and you'd both have an equal share. You could consider the lemonade business at this point has 2 shares, one issued to each of you. You now have _equity_, which is ownership of stock. You each have a 50% _equity stake_ in the business. You agree your share of the business entities you both to vote on business decisions (your share comes with _voting rights_) like who should be in charge of day to day decisions at the table.
Lemonade trade may go well and soon you are making $20 profit a day. You may decide to issue profit to the shareholders (this would be called a _dividend_) or you may decide to keep profits in the business in order to expand.
The spot your lemonade business owns is a good one and you have lots of customers. You also have a track record of managing the purchase and sale of lemonade well. So when you go to a meetup of all local lemonade stands, you find that people are quite keen to own your share of the business (this is because it'll give them access to the profits or a decision in how it's run). In fact you find that there are many offers for you share but the best one is $142. Most of this value comes from the fact that if someone owned your share they'd be entitled to a stream of your share of the profit which works out at $10 a day.
You decline their offers for now but realise from week to week that the offers being made for your share go up and down. People tend to be willing to offer less when you've had a quiet week and profits are lower. Likewise when you've had a good week and _especially_ when other lemonade stands are also doing badly, offers seem to go through the roof. This is how the _stock market_ works with respect to shares/equity. In fact most of the people at the market aren't other lemonade stand owners, they're mostly other kids who want to _invest_ their pocket money somewhere that's going to get them a return (they'd like to own a slice of a successful lemonade stand so they receive a share of the profits - this gets a better rate of return than just leaving their money in the piggy bank)
As time goes on you and your friend find that you're not able to serve all the customers that go past because you can't make lemonade fast enough. You see that an automated juicer machine is $500 so you're not sure where you'll get the cash from but it would immediately help if you were able to buy it. So you go the market and find that people would now be willing to pay $200 for your share of the lemonade stand (business is going well) but the total value of your lemonade stand ($400) still isn't enough to buy the equipment. So you ask the market a different question: who would be willing to lend you the $500? Which you would some interest on. You find that you get a lot of offers, because your business is strong and reliable, and people competing with each other to lend you the money means that the best offer you get is from someone willing to ask only 1% interest (you notice lemonade stands that aren't run so well get offered higher interest rates 5% .. even 10% because the lender isn't sure they'll make all the repayments). So you make an agreement with the person lending you $500. As part of the agreement the overall loans is considered as 5 parts of $100 each. Each of these is called _a bond_ and the process of securing the loan via the market is called a _bond issue_. You notice that the values of the bonds tends to vary less from week to week, because after all they're a pretty safe bet, and highly likely to get repaid. Meanwhile buying an actual share in a lemonade stand might sometimes offer better profit returns, but you notice if the lemonade stand closes down that those who own shares get nothing but the bond holders need paying back out of any remaining cash in the piggy bank. So _bonds are safer than equity shares_ but offer lower returns.
You agree that the lender can swap with anyone else on the market who wants to take over lending you the money. This is because the lender is taking some risk lending you $500 and they might want at some point to reduce that to $200 by selling 3 of the bonds to someone else. The actual value of each bond on the market turns out to be $105 because other kids work out that each bond will not only get repaid $100 eventually, but also get the interest in the meantime. The process of people buy and selling who they are lending money to forms the _bond market_.
Over time you come to notice that the other kids at the market are just part of a wider team. The ones you actually see there are just particularly good at judging the right moment to make an exchange - they're called _traders_. But behind them you have kids whose hobby it is just to understand the running of lemonade stands _really well_. These guys are very good at looking at your sales and how well your stand is run and working out if the offers your getting on the market for your share are at the right value or too high or too low. These kids are _equity analysts_ and they sometimes pay a bit of pocket money to other kids who do special _research_ to give them the inside edge on making good decisions.
After a few seasons of lemonade stand trading you find that one of the biggest risks to your business is that the cost of lemons can go up and down quite widely. In fact, at the start of the season when you're deciding how many cups to buy and how many helpers to hire, you don't yet know if there are going to be loads of lemons on the tree (and the price is lower) or if the harvest is going to be bad (and the cost of lemons high). The worst case for you is if you spend a load of money assuming you'll be able to buy cheap lemons all through the season only to find out later that the cost was higher than you thought. In order to plan your lemonade stand better you go to the market and talk to the kids whose dad owns the lemon trees and see if you can some to an arrangement. What you agree on is that while prices of lemons vary of $0.05 to $0.25 from season to season, for this year you'll agree that lemons in August will be sold at $0.15. You haggle this with each other, based on your priorities, and available weather information, but in the end are both happy to lock the price in. On the market this agreement to buy each batch of 100 lemons at $0.15 is called a _futures contract_. Each contract can be bought and sold to other kids on the market. The person buying it becomes entitled to the delivery of lemons in August. You find that as you get closer to August and lemons are actually in short supply that the day to day price for lemons goes up to $0.30 (this is called the _spot_ price). And the value of each futures contract has gone up in value too. This is because it allows you to receive a batch of lemons, which you could immediately resell for $0.30 if you wanted and make a profit. Because the value of the futures contract is derived from the price of the lemons it's called a _derivative_. The main value of these type of derivative is that it let's you know what your lemonade stand costs will be in advance. The kids who owns the lemon trees also benefits because he knows in advance how much he's going to sell his dad's lemons for and that let's him plan to spend his extra pocket money on his new go kart.
Now that you've locked down a pretty solid and reliable business you look for additional way to drive profits. You notice that the weeks when lemonade sales are worst are when there's a bout of rainy weather and you consider if people are likely to buy umbrellas from your stand when they're not buying lemonade and vice versa. You see that one of the risks to your business is buying lots of lemons at a good rate but then being unable to make a profit due to bad weather. So you consider offsetting the risk of your futures contracts in lemons with an option to buy umbrellas in August. You go to the market and make an arrangement with someone that gives you the _option_ to buy umbrellas at $1 each in August. You don't have to make the purchase, you just have the option to, but if you want to then the other person agrees they'll honour the sale. This is called an _options contact_. Because its value is also dependent on the value of umbrellas it's also a type of _derivative_. The process of balancing your lemon futures contracts with an umbrella option contact is called _hedging_.
edit: typos
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e90b92d5-33c3-4231-afe7-104dc9e8dcc3
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brlx4h
|
if my pupils dilate in the dark to let in more light in order to see more; why isn’t it really bright when they dilate while drunk?
|
When drunk the pupils are slower to react to changes in light level. When light is flashed in the eyes to see if someone is drunk they are looking for a slow pupil response, not dilation.
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16769948-43b1-41bc-837e-c423fc5b3bf5
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brlxnv
|
Why aren't condemned prisoners connected to an EEG machine during execution?
|
The Excecutions are not performed by medical staff. Cause medical staff refuses to assist in such killings. I doubt a non-professional could properly work or read an EEG machine anyway.
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4eed0d16-05db-40ad-beab-45030434a411
|
brlzhq
|
Why do some emotions (sadness, heartbroken etc.) really cause chest pain?
|
A brain region called the "anterior cingulate cortex" regulates emotional reactions. When you experience heightened stress, this part of the brain can increase the activity of the "vagus nerve". This is the longest nerve of the autonomic nervous sytem. It connects from the brain stem to the neck, chest, and abdomen. Overstimulation of this nerve causes pain and nausea.
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3e8904fa-c64a-40df-a64d-f4c44412db36
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brlzmg
|
Why does pain come in waves and what's happening to the injured part when there is no pain, compared to when there is pain?
|
You're right that it's not just the nerves resting. That process does happen but it's very fast (fractions of a second). Instead, this is caused by the brain itself getting fatigued by the constant input from the nerves and blocking them out. Then after a while it's rested and ready to accept the input again.
You can see this same sort of thing happening if you stare at a pattern for a while. You'll see the pattern fade out, with the light parts appearing darker and the dark parts appearing lighter, until it's hard to see the pattern anymore. Then if you look at a blank space, the reverse of the pattern shows up. Your eyes and brain are blocking out the stimulation of the pattern, so when the pattern goes away the block actually creates a reverse pattern. However, if you instead keep staring at the pattern for a very long time, you'll begin to see parts of the pattern fade in and out as your brain's block fades and is replaced. This corresponds to the waves of pain you're talking about.
Basically, your brain is able to get used to the pain, but it keeps checking occasionally to see if the pain is still there.
|
0752bccd-a00b-43c5-9155-48b0ed791b09
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brmjbq
|
Why do men get bald and women dont?
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ELI5: Baldness is caused by the male hormone dihydrotestosterone (DHT) which females have in very small amounts
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392a4ae0-81da-49bf-b1c5-8737fba2a47e
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brmqu9
|
Why is it that sometimes when you take caffeine that only your heart beats faster but your mind stays tired (or becomes even more tired)?
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I guess it’s only a temporary central nervous system stimulant and it can’t really replace lost sleep. It might temporarily give your body a boost but if you’ve only had two hours sleep then you’re probably gonna be tired no matter what. Plus, you’re probably gonna crash hard after the initial surge. It’s not a miracle worker :P
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6d4e8927-d57c-46b4-aead-179a5e779913
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brmz77
|
What is the glymphatic system, and how does it work?
|
Uses specialized fluid and neural paths in order to clear waste from brain; it's the brain's sanitation department. Wiki glymphatic system for further explanation.
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ca0052f7-18eb-4128-a21b-bde7089dc3ac
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brn8jh
|
What's the digital process of lowering the quality of a photo or video? Also is the opposite process a thing or just movie things?
|
Lossy compression.
The opposite is largely just a movie thing. Only in the last few years has machine learning-based image interpolation become a practical thing, but it's just *interpolation*, basically an educated guess. It's reasonably good at sharpening some contours on upscaled images or guessing a generic replacement for a missing part of an image from the surroundings, but it's not some magic "enhance" that can bring back data lost in compression.
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a1b9099a-6d10-4323-a47a-4fe638778b22
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brna2t
|
Why does exercise improve your cardiovascular health, but doing other things that increase heart rate like drinking coffee and snorting blow don’t?
|
When we say Cardiovascular health or fitness we are talking about an overall strength or endurance in the major muscle groups as well as the heart itself so a person with that type of fitness can run or cycle or walk for a long time/distance or otherwise do feats of physical prowess.
Raising the Heart Rate without putting the skeleton or muscle or tendons under any kind of stress as exercise does would make the heart itself slightly stronger just as those devices that send a slight electrical charge into your abs , causing them to contract will strengthen them BUT without an all over body workout that person wouldn't see any improvement in long distance running etc which we describe as "cardio" fitness.
In addition, a stronger heart gained from exercise will have a lower resting heart rate because the stronger heart only needs to beat a smaller number of times per minute to pump the same amount of blood around the body. A heart that is beating faster because of coffee or cocaine will continue to beat faster for a long time as the drugs stay in your system so you don't get the same benefit of a lower HR when resting since there is less resting time.
Another factor is that exercise raises your HR way more than coffee does so it makes the heart much stronger than drinking coffee would.
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9c4bc8a2-332e-4f3a-bf3d-e00d434bca3e
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brnh9s
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Why are the majority of space rockets made in white instead of other colors?
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I'm not sure for rockets, but I know planes are white mostly for two reasons : white paint is cheaper and it's easier to spot technical defects on a white surface.
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b3b93ffe-ec7c-4ca9-a043-39ffa1c62bd1
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brnm26
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how does acute radiation poisoning induce vomiting, nausea within just tens of minutes of exposure, and in more serious cases, instant loss of consciousnesses?
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Radiation is especially damaging to soft tissues - skin, blood and blood vessels, GI tract, brain and nerves.
If you get a full body dose, the GI tract (stomach and intestines) are damaged and thats where the vomiting and nausea come from
Platelets are damaged and wounds and burns hemorrhage without an ability to stop bleeding
Take a big dose to the head, the brain and nerves are damaged, and along with the bleeding, it's a terrible, terrible thing
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beadea63-383b-4d14-8c7a-e77979ad3541
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brnv42
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Why are the storage options for devices like phones or laptops multiples of 16GB?
|
computers are based on a binary system so it goes up in powers of 2.
The math starts at two not sixteen but its:
2^1=2
2^2=4
2^3=8
2^4=16
2^5=32
so on and so forth right up to 1024 when we move to 1 Terrabyte.
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8d9cc235-f3d9-46d2-8caa-321e08c3f138
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bro6tx
|
Why can some video games host 10s of players with no lag while others can't seem to host a lag-free 1-on-1?
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Without even trying to explain what causes lag, the short answer is that some programmers know what they are doing and some don’t.
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29dfa7f1-0e7c-4e0c-8885-abf8b724a678
|
broktg
|
Why does cable cost money when advertisements are broadcasted through each program, while other services are free to use because they utilize advertisements?
|
So you’re missing about 75% of the situation.
Literally getting that cable into your house, having the infrastructure to run it and so on it’s a wildly complex and expensive business. Wildly. Telecom is a very difficult business to be in.
Secondly, on the ads, for a “average” cable network, they only make about 50% of their revenue on ads. The other 50% is in “carriage fees”. That is the cable company pays to show the channel to their customers. Big networks like ESPN, Disney, or TNT get monster rates for each cable customer.
The cable company has to pass on two big things to the consumer that becomes your bill: the cost of operating the company, and the cost to carry the channels. Both are enormous.
Which gets to a strange point. Really the infrastructure cost is fairly “set”. It’s just the cost of actually getting you the cable. So what your cable bill really is going to is the networks like Disney (via carriage fees).
The margins for video services from cable companies is currently very very low...many companies even lose money giving you video! I know you scream at your bill being so expensive, but really it’s true, video service margins are shit.
People love hating on cable companies but the real deal is that they are more of a middle man that just gets a little slice of each customer.
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2bf64463-774e-47a1-b308-8d69b373c9c2
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brornt
|
What causes glitch worlds/levels in video games?
|
The following is *technically incorrect* but *conceptually correct* - simplified for ELI5 purposes.
Level data in, for example, a Mario game, looks like this:
AAAAAAAA
AAAAAAEA
AABBAABB
AACCAACC
AACCAACC
DDDDDDDD
Where A = empty space, B = top of a pipe, C = vertical pipe, and D = brick ground. E = empty space with a Koopa in it. All 24 letters have some different tile and/or enemy associated with them. (In reality games don't use letters, but might use bytes with 256 values, or 2- or 4-byte pairings etc... but I'm simplifying things here)
(Also, obviously most Mario levels are way bigger than 8x6 tiles, but I'm not typing out more than that!)
When you enter a new level, the code says "OK, go to the 38,794th line in the code and read 6 lines starting there to get the level data." But sometimes that "38,794" gets corrupted by some bug, and instead the program reads "OK, go to the 12,804th line of code and read 6 lines starting there to get the level data." And what do we find at the 12,804th line of code?
THE_PRIN
CESS_IS_
IN_ANOTH
ER_CASTL
E.______
WELCOME_
Uh-oh, it's actual text, meant to get displayed in another place. But our level-building routine doesn't know that. It just sees letter-codes for various tiles. So it builds a level using those codes. T is a question block, H is the left side of a cloud, E is empty space with a Koopa...
The end result is a nonsensical jumble when viewed as a level.
|
cebbf51f-0de2-4cd5-b4c3-26c592d6918a
|
brotpu
|
What’s the difference between psychology and sociology? What’s the difference between sociology and cultural anthropology?
|
Sociology focuses on groups/ multiple people as the unit of analysis, while psychology focuses on the individual. There is overlap because each field recognizes that the individual is never "just" an individual but always influenced by others (and even takes the perspective of others in its own minds).
Sociology is broader than cultural anthropology, and comes from a different academic disciplinary history, but includes the same topics: the meanings, practices, and artifacts of a particular culture, and how they work. Sociology also includes lots of topics besides "cultural meaning" itself, and many levels of analysis, from social psychology to economic behavior, to history of politics, etc.
Source: PhD/ B.S. in sociology from two top tier American universities
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14da5b7d-4a73-4f95-8d32-d301f8589704
|
brow6j
|
What is Sensory Overload?
|
Too much stuff for your senses to keep track of happening at once - a lot of stimulus can become disorienting.
|
f888b329-ed4f-4999-8e9f-560285795f2b
|
brp1bz
|
How does “Hollywood accounting” work?
|
Lets say big movie studio like Warner Bros wanted to make Forrest Gump 2. They would make an 'on paper' company (to make the movie) called 'Forrest Gump 2 Movie Company' then charge anything they wanted to the Forrest Gump company. Basically huge fees and although the film is a smash hit, they (Warner Bros) can make it look like it has not made a cent in profit because Forrest Gump 2 company still owes them money.
That's how actors etc can be in a profit share contract of a huge movie but not see a penny from their profit share cut
|
cb0013ea-8c3f-420c-a885-4610e0ebbdab
|
brpawd
|
What is hyper threading and the ZombieLoad vulnerability?
|
ZombieLoad is an attack that uses a vulnerability in the so called "speculative execution" of a different process running on the same core of the processor.
Imagine that the processor running code is a car going down a street. Every once in a while, it comes to an intersection where it has to turn left or right. The car does not yet know this though - it has to look it up first, and until then it's just standing still.
With speculative execution, the car will create a ghost car which will guess which direction is right. Once it finds out which direction is right a little bit later, it will either warp to the ghost car, or it'll delete the ghost and start over from the intersection, going in the right direction this time.
Hyperthreading allows another car to drive in the same city. They can normally not see each other - but with ZombieLoad, they can see the ghosts. And by observing where these ghosts are going, malware can possibly find out what it's doing and extract sensitive data.
> Should I, an average computer user, be worried? I’m reading that installing the patch could slow my Mac down by up to 40%?
As far as I know, the vulnerability isn't as problematic for end-users as it is for companies using cloud services such as Microsoft Azure or Amazon Web Services to run their software, possibly with sensitive data. But I'm not a security expert, so I don't want to give you any recomendations about what to do in this case.
|
2bb27646-9aa0-415c-8456-2920bc487aa8
|
brpfr6
|
What are the things you see in the distance on the road on a sunny day that look like water?
|
Air currents make this shimmer, similar to a reflection of the sky on water, hence causing the illusion of wetness. Mirage is an optical phenomenon very common in sunny days. The sun light in the direction of the road gets refracted do to the temperature gradient (continuous change) of the layers of air.
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32e3f7e5-5d66-4e59-9630-60b5d34763f6
|
brphd5
|
Why was I not killed or even hurt from an electric shock?
|
The effect of the shock depends on many factors. A wall outlet is rated to provide *up to* 15 or 20 amps, but the actual current delivered depends on what’s plugged in. Human skin has high resistance so you’d only get a few milliamps of current. Also, the harm depends on the path the current takes through the body. If a few milliamps cross your heart, it can kill you. In your case, the current was limited to traveling across your finger, since it was touching both prongs. There are no critical organs or muscles in the fingertips, so current across the finger could result in burns at worst.
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6dfb1dfb-19c9-4887-b8c2-195ddb11e1a1
|
brq1kl
|
What does it entail when a business is “100% employee owned”?
|
I work for an employee owned business, so my information is based on how my company works.
The founder of the company put all the company shares into a trust, this trust stated that the employees were equal owners of those shares and were to be given the dividends that shareholders would get. This means that rather than publicly trading the shares and offering dividends based on the success, the employees get the dividends. This takes the form of a yearly bonus based on the profits from the previous year. This is as a percentage of yearly pay, including overtime. But the % is equal for all, so everyone gets 5% or 10% for example.
There are other restrictions too, like how much the chairperson can be paid as a multiple of the average basic wage of the employees, and a part of the company board is elected employees from across the business.
|
353ea367-93ad-45a2-b169-bbe44fca782a
|
brqeeq
|
The volume for the shape of a cylinder is pi(r)^2xh. Why is this not the same calculation for determining the volume of displacement in the cylinder of an engine?
|
It should be the same calculation. Who told you that it isn't?
|
36c2caab-6b33-4ba5-97e8-8ee2e159f868
|
brqhlh
|
How do home users use virtual machines
|
The same way everyone else does.
Software testing, running legacy programs that no longer work on modern OS's, encapsulation to help prevent programs from interfering with others, running virtual desktops for thin/zero clients, honeypots to catch hackers, etc.
The only difference is that VM's at home are much less common than in the work place; And that VM's at work typically run on dedicated servers, usually through the OS called ESXi. Where as a home user will probably just run it on a normal desktop PC.
|
f1dd16b3-ec95-45a3-a9ef-3fcc718ede25
|
brqi1n
|
Why do remote controls use infrared light instead of other wavelengths?
|
Very low wavelength bands are already occupied by radios and microwaves and have a lot of noise.
Visible light is visible of course.
Ultraviolet is too energy intensive to generate, and you definitely don't want to be shooting x-rays around the living room.
So the near-IR it is.
|
fb2ee82f-0a8d-4ebe-8bba-51d00542c66f
|
brql5c
|
Why do passenger planes keep life vests and no parachutes under every seat?
|
Becuase at the levels your flying, if you were to exit the plane with no oxygen tank you’d just pass out from asphyxiation so you can’t operate a parachute
|
350f3f22-dcee-4d9c-a235-0ec3b5bca958
|
brqrwo
|
How do bonsai trees work?
|
The tree is limited in how far it can grow, its roots can't spread and its branches are pruned. The tree still matures, it still becomes an adult organism, but it never reaches its adult size, mainly because the lack of roots and leaves stop it from getting enough nutrients from growing that big.
The apple is its offspring, and isn't so limited. The tree still has a tough time getting the resources needed, likely why there was only one apple, but as far as the cells at that branch tip are concerned it's a normal adult tree making a normal apple, which is therefore full sized.
Think of it like an amputee; an amputee who's lost all four limbs is going to have a child with all of its body parts, they won't be smaller than a normal baby and they won't be missing bits.
|
e210d767-f102-40b6-9721-cc259053ee29
|
brqtie
|
Why is it much easier to put a ring on a finger than to take it off?
|
Because divorce is a messy process.
But really, I think the main issue for most people is that there is more flesh the closer on the finger you get to the palm. When you try to remove the ring it tends to drag flesh toward the knuckle which forces it outwards, expanding to keep the ring in place. Putting it on from the other side of that knuckle there is less flesh available to move, and being narrower less likely to be pulled along.
|
3a6cba71-7216-439b-8554-55acc5261994
|
brr00x
|
How do scammers send you an email from your own account.
|
Think of receiving an email like getting a letter in the mail. It’s fairly trivial and there’s often nothing enforcing someone from writing whatever name they want as the sender on the envelope.
Letters have envelopes, and you can write whatever you want on them. Emails have “headers” that contain information like the sender name/email, the subject, etc, and you can forge information in the headers just the same.
Edit: And to continue the envelope analogy, if I mailed you a letter but put your name/address as both the from and to addresses, there would be evidence that you didn’t send yourself the letter: the postmark would be from a different city or state. And the same thing with forged email headers - there is evidence in the headers that will clearly show you it was forged if you know what to look for.
|
f17fc5c3-416b-4576-8b1b-02a604a5882f
|
brr1r6
|
saw spiral shaped rain line in radar today, any explanation? (pic in comment)
|
I am not sure what made you think that it's going clockwise. If you look at an animated map, you can clearly see that [it's spinning counter-clockwise](_URL_0_).
|
42ff61e8-fd8c-46ed-beac-74aa1b608785
|
brr1re
|
how do radio signals (4G, WiFi etc.) manage to retain their information after passing through trees, buildings and other obstacles? And how are they not mixed up, intertwined?
|
They are, the key is there are error correction and detection algorithms that work to counter the problem. In bad environments they don't always work.
Also, many newer devices actually utilize the attenuation and reflections to improve signal quality. Take a look into [MIMO](_URL_0_) technology. They do what is called [beamforming](_URL_1_) where they vary the signal being output on multiple antennae to create hot spots in the signal at the receiving antenna(e) to improve reception. When multiple devices are connected it will actually change the beam forming per device moment to moment depending on the destination. It's really cool stuff.
Edits: Links, typos.
Edit 2: Figured I could expand as well. When you're dealing with reflections or other signals that could potentially interfere, they are usually a bit weaker than the main signal. This means that a receiver can filter them out by simply ignoring signals that are weaker than a certain level. This is called the noise floor of the radio. Think of it like being in a room full of people talking and ignoring all the background conversations because they're harder to hear and focusing on your current one.
Attenuation of the main signal works similarly. As long as the signal isn't attenuated below the noise floor, it will work. If the operating environment for the radios is bad enough, it may be impossible to get a strong enough signal to overcome the noise floor, and then nothing works.
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f6b9daef-b40b-4a44-bdb0-d9536a739977
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brr27q
|
What is the difference between sitting in a sauna vs sitting in a car left outside in the summer heat? Why is one regarded as healthy and the other often fatal?
|
Both can be fatal, dry and wet saunas both have serious health risks due to overheating.
The difference is in a car, typically a young child or a pet does not have the ability to leave. So they're stuck in a car, while their body temperature rises to fatal levels.
|
726e18b9-83b3-469b-a7e4-6c74b3b6b62c
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brr4ue
|
How come a foot or two of brick/plaster can stop a cell phone signal but (moderate) hills and densely packed buildings in urban areas do not?
|
Hills and buildings in urban areas do block cell phone signals. A Lot.
In cities cell companies put relays on the tops of buildings to spread coverage from the main towers and prevent dead zones.
In areas with hills they will but relays or towers on said hills.
But in both cases you will have bad coverage in some parts of a city, and you will have hills making dead zones in rural areas.
|
65ff45a5-8f1d-4461-8039-7032143959d0
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brr6jf
|
Iterative vs Agile model?
|
Agile is not mutually exclusive with iterative. Agile approach is about delivering business functional pieces as quickly as possible. Iterative means you're going over the same area to refine the functionality. But you can iterate over months or year without ever delivering to user. Agile approach involves the product team and dev team to work on and deliver pieces of the product as they're completed, rather than waiting until entire product is finished to deliver.
Agile is game expansion packs. Waterfall is waiting 5 years for new game.
|
4e9b77ea-19f7-40de-9856-862723df9110
|
brrdhr
|
Why is there a delay when a TV guest is being interviewed via satellite in 2019?
|
There will always be a delay because the electromagnetic waves carrying the signal travel at a finite speed, and the electric circuits which process the signal at all intermediate and final steps can only work at a finite speed.
Even though they work incredibly fast, it's still not instantaneous, so travelling over far enough distances you are going to notice the time delay.
|
35861659-c458-45ee-9cbb-b1c69410ad78
|
brrj3l
|
What exactly happens to the weight you lose from intense exercise?
|
During exercise you lose weight through sweating. Simultaneously, you lose weight (all the time) by exhaling CO2 and water vapor — the food calories you eat are removed, in part, by that exhalation of breath. Some of the energy your muscles generate during exercise go to operate your muscles, and some of that energy is removed from your body as heat in your muscles.
|
a1a377ef-bdb9-4bb3-bfa7-9268a9d10fc8
|
brrrk9
|
Why is it that babies like being rocked to sleep yet as we get older rocking can be uncomfortable such as on a boat?
|
The womb is a fluid-filled sac, and when a mother moves about the baby is very slightly rocked thanks to that fluid. The baby becomes used to this feeling before birth, so rocking helps to calm them afterward for a time.
Adult humans don't live in fluid-filled sacs. We're not used to being moved or rocked outside of our own willpower.
|
81cdd68e-a655-401b-8749-267736866d1a
|
brrwvi
|
why most meals taste better when they are warm?
|
The majority of taste comes from scent, not from contact with your tongue. Scent relies upon molecules getting into the air, which is *much* easier when the food is warm, or better yet, hot. You can simply smell your food better when it's warm.
This is the same reason why airplane food tastes so bad; low air pressure means there's a lower density of scent molecules meaning you can't detect it as well; therefore, it's bland.
Now, as for a more speculated set of reasons:
* You might be more culturally attuned to eating warm food. (i.e. you learned that warm food is good food, so you perceive cold food as worse on principle.)
* Humans have physically evolved to eat cooked food (which, btw, gave us smaller jaws and wisdom teeth that don't fit in our mouths). Food that is hot is safer and easier to eat than food that is cold (possibly raw, possibly bad). Our sense of taste is explicitly there to make sure we only eat safe and nutritious things (ignoring modern processed foods).
|
ffee06db-d3fe-4379-b48e-7838748be68d
|
brs0fj
|
if Spotify can stream what seems like every song ever recorded, why can’t Netflix do that with TV and movies?
|
There are a smaller number of copyright holders in the world of music. A huge percentage of music copyrights are held by the "Big Three" - UMG, Sony, and Warner. Many smaller record labels are in fact subsidiaries of one of these three. These three companies, particularly UMG, have taken action against audio streaming platforms to *prevent* exclusives; they can threaten to take away a huge chunk of a streaming platform's revenue if that platform attempts to have an exclusive track which other platforms cannot broadcast.
Additionally, there are rights management business like ASCAP and EMI in the world of music, whose sole job is to sell rights to music usage and to make sure rights are respected. The existence of these organizations helps make it easy for music rights to get sold to streaming platforms.
In comparison, the video market is very different. Rights ownership may be more fractured or complicated. Studios are far more interested to retain exclusive rights; in part because people will listen to music over and over, but very few people will watch the same movie every single day. This makes the rights to a single movie a much more valuable commodity; each individual watch of a movie is more rare, and thus worth more money. The bargaining is shifted to the rights holder, and they can and will hold out until a streaming platform offers them a lucrative deal.
|
e3d58270-d653-453a-9969-3cc1088d6c19
|
brs2z3
|
- I see these references on cops movies: "He works at 3-6", "I work at "5-4"... what are these numbers? It cannot be precinct number because there is a reference about a cop working at "5-4" but the precinct number shown by the camera is 12th Precinct NY.
|
Hollywood is Hollywood, what they say may sound cop-ish and might not be accurate for all or most law enforcement agencies.
Depending on the jurisdiction, a police department have their area divided into precincts and those precincts might be further broken down into beat numbers.
So officer 1 would work for a certain precinct, be assigned to a certain unit such as patrol, homicide, gang, narcotics, robbery, etc. Then they could be assigned a beat (especially patrol) and possibly a certain shift.
For example this is the Chicago PD's beat map
_URL_0_
Perhaps r/askleo and r/asklo might be better subs.
|
451f95d5-d4b2-4c72-921a-7f307cfe9844
|
brs6yn
|
What is the purpose of adrenaline shots and what can they actually do?
|
Adrenaline shots are epinephrine. Its a chemical that narrows blood vessels and opens airways in the lungs which can reverse severe low blood pressure, severe skin itching, hives, and other symptoms of an allergic reaction. Dont know all the limitations, but I know you can't use epipens on anyone under like 20lbs.
As far as ODing, adrenaline WILL restart a heart, potentially, but boosting your body with that much doubles the likelihood of brain damage. Like I mentioned above, it constricts blood vessels, making it easier for your heart to pump blood when it's restarted, but smaller tubes means less oxygen getting carried to the brain.
Its also way more than your body would normally use at once.
|
35d2a390-0433-4b18-b6d8-479a5215fd54
|
brswpl
|
Why do paper cuts not hurt when we don't notice them but hurt once we do?
|
Or maybe you only start to notice them when they start to hurt?
|
e311d3c5-c542-4f78-ab2d-5fc847632034
|
brtanv
|
how come kids can be preoccupied with one simple thing endlessly and adults seemingly don’t have those kinds of similar fascinations
|
Adults certainly can be fascinated with one thing for countless hours, that's what our scientists and researchers are doing essentially. We think it's simple because we as adults already understand what is going on but think about all the stuff that even adults don't fully comprehend.
|
858f4745-bc95-4e02-b6f9-5c81f59d28cc
|
brtgdn
|
Why do some cuts leave scars and others don’t?
|
There are a number of factors that go into whether a cut will leave a scar.
hypertrophic scars or keloid scars are raised scars that come from deeper cuts, where your body spams collagen proteins haphazardly to try to get the wound closed as quickly as possible.
If the cut is a regular shape it is easier to heal. surgery incisions are usually straight lines made with a very sharp scalpel so as not to tear the edges and create any ragged flaps of skin that will be difficult to heal. Some weapons are created specifically to have a nasty shape that will create wounds that are difficult to heal. Irregular wounds are more likely to scar.
Also cleanliness can determine scarring. if your wound is clean there is much less likelihood that it will scar.
basically, scarring is your body freaking out over a wound and just throwing material at it to get it closed. if a wound is clean, shallow, and an easy shape to heal, then your body won't spit extra proteins at it.
|
76cd2e6c-4510-4ba7-ba8a-d26e031029d5
|
brtu7z
|
How is nutrition cooked out of food?
|
If the food is boiled, then some of the Vitamins contained may leach out into the water; this is especially noticeable with Vitamin C. Effectively, certain nutrients are "water soluble"; they dissolve in water, and are washed away by the water that is boiling the food. Additionally, the heat can break the nutrients down into stuff that isn't particularly useful to us.
|
d919af7a-b743-45c9-bb7f-0977c7732774
|
bruhys
|
Why do women wear skirts and men wear pants?
|
Socially constructed gender norms. These things change all the time, and will change again. There is no real reason for it other than what society deems as "normal" and society changes its views all the time.
|
b0513f3b-3b21-4d8c-b000-4b37a8b407ae
|
brujrt
|
Why do corn chips (Fritos style) have ~50% more fat per same size serving than Tortilla Chips (Tostitos), given both are made of the same ingredients?
|
I would suspect 2 things: one, different definitions of serving size (bulk quantity of mass). And two: Fritos are VERY “wet” and greasy compared to most chip brands.
The fat is mostly from the oil. So greasier chip means more fat
|
35124f54-4788-4cfd-b279-fbed853f5f34
|
brulep
|
What causes the shudder that occurs during urination?
|
Did you re-ask this? I too get goose bumps or chills when relieving myself. It can't be so uncommon
|
d9bfec70-697e-4e35-9850-ffc917a1394a
|
bruspw
|
Why do the water levels in toilets never go up. Surely the water levels would rise the more you urinate or defecate.
|
here is a great little video that shows how the trap on the inside of a toilet works to keep both the bad smells from the sewer in the pipes and keeps the water in the bowl
_URL_0_
|
1ad6bee4-ba0f-4a65-a37b-3b330d9385b4
|
bruxkr
|
How does buprenorphine and naloxone interact with each other in Suboxone? I've heard that buprenorphine is more potent than morphine, how does the naloxone prevent this?
|
Naloxone is not well absorbed orally while buprenorphine is. At high enough dosage, the effect of naloxone (which blocks opioid effects) does start to become significant, which decreases the effect from dose escalation. The biggest reason is for injection though, as naloxone is fully active there, and injecting will not give you a significant high, and might even precipitate withdrawal.
|
fa581307-8063-4596-ade2-1c5fefece86f
|
bruyez
|
Why the "black color" in TV screen are not black?
|
It's because instead of the tv turning off pixels to show black, they are just showing the minimum possible light. You should look into oled panels. They are pricey but should give you what you're looking for
|
a13e2593-e9c4-4a7b-8c67-8dee50d9cdf4
|
brv22k
|
How are international treaties "binding?"
|
They can't be enforced, they depend on the good faith of both parties. If course of you renege on your obligations under a treaty you agreed to, then you will find it difficult to get anyone to trust your word again.
|
72f15354-d76d-4a50-86ac-43c0d132d664
|
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