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|---|---|---|---|
bp4msa
|
How was ignition timing and air:fuel ratio controlled before ECUs?
|
You need a carburetor, 2 coils and some sort of crank trigger.
The carburetor handles the air fuel ratio. Just suck air in and the air will have the proper air/fuel ratio. The carb should also have an accelerator pump to shoot extra fuel into the carb when jumping on the gas. Lots of good used carbs available.
Fuel can be fed to a carb either with gravity fill or a low pressure pump. One line, no return line.
The ignition would have a coil per cylinder. Since it is a rotary, you can trigger right off the crank. Every time the magnet passes a sensor, the spark plug fires. either the magnet or sensor can be movable to adjust timing.
Oil pump, water pump, alternator all need some sort of pulley setup.
no ecu needed.
|
6f7cdc23-8399-40e8-8fc3-fe85245ccd62
|
bp4vat
|
Why do nearly all doctors refuse to tie the tubes of a woman under 30?
|
I’m actually guessing it’s the same reason why most tattoo artists don’t tattoo drunk people; chances are high people will regret the decision
|
ea31ca9b-3d75-4785-86d1-0bee59c64669
|
bp4ytg
|
Why are bicycles able to stay upright when moving, and not while stationary?
|
Aha I know this one!
The bike wheels are acting like gyroscopes, the spinning keeps the wheels moving forward and as long as they're spinning it'll stay upright because the energy required to knock it over is *more* than the energy needed to keep it upright.
This is why when you push a bike, say down a hill, it'll like stay moving for a while unless it crashes or slows down.
There's a lot more complicated applications of this concept but I feel this works for an Eli5
EDIT: You can test this concept yourself by putting a [bike wheel on a string](_URL_0_) and spinning it really fast. It will right itself in the air. Its a common expirement in introductory physics courses.
Source: am a physics student.
|
754526a4-951c-49df-9d13-9828f4532b2f
|
bp59hu
|
How do stocks work?
|
You buy a cookie for a dollar and don't eat it. Later on your friend sees this cookie and offers you two dollars. You sell it to them. You made the dollar you spent back and made one extra. Replace cookie with stock and that's essentially it (making money anyway)
|
d34b92d4-eb8e-437c-8956-392b8da68031
|
bp5d5x
|
How does a digital thermometer measure the temperature?
|
There are a number of different types of electrical temperature sensor. One of the most common, robust and cheap is the thermistor which changes electrical resistance with temperature. That is used in a circuit which gives an output to drive the display depending on that resistance.
Other types, more used in scientific rather than domestic equipment, include thermocouples which generate a voltage depending on their temperature and platinum filaments which again change resistance.
|
80b4dd6f-7491-48f1-ab44-e2604024cda3
|
bp5fot
|
How does radiation poisoning work?
|
Exposure to radiation damages the DNA in cells, which makes it impossible for them to properly reproduce, or in very large amounts, kills them outright.
Because moderate to severe damage impedes cellular reproduction, the effects are most pronounced in cells that reproduce rapidly like in the gut, bone marrow, and skin. Acute fatal radiation poisoning basically causes your body to fall apart. Cells die and cannot be replaced, and that causes extensive bleeding, inability to produce new blood cells, and inability to gain nutrients from food.
|
98b10838-fea8-45f2-94ec-f192eea516a2
|
bp5h6t
|
Why Do Wolves Howl In Unison?
|
Wolves howling in unison could have many different meanings but put simply, it’s still just their form of communicating... Sometimes it’s between a member of their pack that has been lost or sometimes it could also signify to other wolves that the area the pack are howling in is their territory thus, other wolves shouldn’t enter.
|
1c2f427c-6a76-4a23-835c-24a08fb743b6
|
bp5r4o
|
How is a water molecule shaped like it is? Since oxygen is more electronegative than hydrogen, the 2 hydrogens are positively-charged. Therefore, shouldn't they repel each other giving water a molecular structure similar to carbon dioxide? The charges would then cancel. So how is water polar?
|
There are two additional electron pairs on the oxygen. So two hydrogen's and two electron pairs forces a tetrahedron structure. Carbon dioxide is linear because there are no additional electron pairs.
|
9872b878-a32d-435c-9b3f-c704bcc9b1fe
|
bp5w8r
|
Why isn’t possible for all cars to move in unison when a red light turns green instead of seeing a green light and having to wait a few seconds before you can move?
|
It's to do with the spaces between the cars. At the lights there's only a small gap, and if all the cars started together then the gap wouldn't grow and if someone hits the breaks there would be an accident. By waiting a second for the car in front to move, you create a safe gap between your car and the car in front.
|
6eb43cdf-593d-429d-979a-5fc5badda850
|
bp64u4
|
How can I make sense of classical music hierarchy and structure (such as "Opus no. and Symphony no.)?
|
An opus is just another word for "work". irrespective of kind of wok it is (a song, a quartet for violin, a piece for piano or whatever). So the first known work for a composer is "opus 1", the second one is "opus 2", and so on. Symphonies are a special kind of works, namely for a Orchestra. All the instruments together they sound well, thats the literally meaning for "symphony", meaning "all together (sym) sound (phony)". These big pieces are generally numbered in their date when they were written. So e.g. Beethovens first symphony was written before his second one and so on. Symphonies have an opus number as well but because symphonies are regarded as major works, their opus numbers are usually neglected.
& #x200B;
All those numbers makes it easier for the listener to understand the development of the specific composer during his career.
|
e831ce9c-abb4-40d8-b492-3566424e3068
|
bp6h82
|
What’s the difference between jelly and jam?
|
Jelly is a gelatinous spread produced from fruit juice.
Jam is a a gelatinous spread produced from pureed fruit.
Preserves is a gelatinous spread produced from pureed and smashed fruit having chunks of fruit in it.
Marmalade is a specific kind of Preserves made from citrus fruit involving a significant amount of the zest of the fruit.
|
c67625a7-189d-4ba8-9aea-60312917a91d
|
bp6jf5
|
How are computer parts manufactured to be so small?
|
Very very carefully!
To be more serious, the smallest things that are manufactured in volume are "Integrated Circuits" (ICs). For example, microprocessors or Graphics Processing Units (GPUs) can contain billions of tiny transistors on a piece of silicon the size of your thumbnail. Each transistor is many many times smaller than the diameter of a human hair.
There are a few key components of making something this small.
One is "photolithography". The pattern you are trying to make on the silicon wafer (or a layer of something deposited on the silicon) is defined by shining light through a "mask". This mask has clear areas, and opaque areas. The light hits (or doesn't hit) the photoresist, a light sensitive layer deposited on top of the Si wafer. This changes its chemical properties, making it easier/harder to etch away (depending on the type of photoresist). This essentially allows one to re-create the mask's pattern or its negative in the photoresist, and thus on the materials on the wafer.
To make really small things this way, you need to either have a very small mask to start with, you need to reduce the image down using lenses, or both. Modern IC manufacturing does both.
The mask is made in a process similar to what I described, but of course there is no mask. There is a very transparent quartz glass coated with a metal like chrome, and that's coated with a photoresist. Instead of using a mask to expose the photoresist (or not), the image is written directly on the photoresist with an electron beam. This is a slow process, but once you are done you have a very valuable mask with tiny features.
And to make those features even smaller when doing the photolithography process on the Si wafer, a very very good set of lenses is used to reduce the size of the mask image.
|
73523753-3f3a-4cec-8160-59c6fdf56b7d
|
bp6k8g
|
Why do sunsets look different in different parts of the world?
|
Altitude and local air pollution are the two big things. The colors come from light bending through the atmosphere. Light will bend more with lower altitudes and higher air pollution then with higher altitude and lower pollution.
|
8c9b3941-d8a2-40bf-b591-14f0298edbe4
|
bp6o0k
|
Why US college educated need to go to another school to have their chosen profession?
|
I don't think anyone has touched on this aspect of your question yet:
4 years of college is not just a generic education unrelated to your profession. You declare a major, and you'll have a specific set of requirements you need to fulfill. *Some* of these classes are unrelated (gen eds), but you start taking classes related to your desired profession at the very beginning.
For example, my degree program requirements include:
**Core**
Element One—Communication (2 courses)
Element Two—Mathematics (1 course)
Element Three—Global Traditions (2 courses)
Element Four—Arts/Humanities (1 course)
Element Five—Social Science (2 courses)
Element Six—Natural Science (2 courses)
Additional Core—choose 2 additional Core courses from the above elements.
Students in my university choose any class that would satisfy those requirements (and there are many options).
**Then for the rest of my degree program:**
One specific English class
One specific chemistry class
2 specific physics classes
4 specific math classes
16 specific engineering classes
3 engineering tech electives (your choice)
3 engineering courses that complete a "track" (there are 3 track options)
Senior lab (2 options) & senior project (each project is unique)
|
b0c74552-b071-4376-a915-6c56f744d38c
|
bp6t26
|
Can sundials also give information about month?
|
An [Armillary Sphere](_URL_1_) does what you’re thinking of.
It’s an oriented sundial that will display both clock time and months and seasons.
[the various rings and their use](_URL_0_) are explained in this link.
|
24c06f3e-145c-402a-81d3-a7ea2a22586d
|
bp799c
|
Why are penis vein patterns so different from penis to penis?
|
Everybody's veins are a little bit different. The same can be said for iris and retina patterns, and for prints from the nose, lips, tongue, and ears besides fingers and feet.
|
820d9c05-9f57-4956-9341-e6f0ffb7c3b3
|
bp7dw1
|
How are there so many drugs in prisons?
|
I work in a jail and tbh a lot of contraband is brought in by officers. Maybe some trustees.
|
95d017cf-d3c8-4aec-85d4-bf5a65f25389
|
bp7jd8
|
What is happening to your skin when itchiness occurs?
|
Your body releases a chemical in the area that stimulates the nerve endings in a way that triggers the desire to scratch that spot. This is in response to the presence of something foreign that needs to be removed.
I think that’s it but I’m a moron so I am also probably very wrong.
|
5339d592-5609-4576-9849-ef9ba07ae887
|
bp7o53
|
what makes coffee and tea decaf as opposed to full of caffeine?
|
Decaffeinated tea and coffee use various methods to remove the caffeine. One of the methods just uses water - the caffeine dissolves easily into the water, and then other solvents can remove the caffeine from the water. Of course, the water also contains the chemicals that make it taste like coffee, so the caffeine-free but coffee-tasting water is then cycled back through - as it is saturated in coffee, it doesn't take out the coffee flavours, but dose dissolve more caffeine.
|
41a9d9e4-3728-4c46-9dbe-05972f323325
|
bp7wcq
|
why is tipping a thing in some countries but not others?
|
Because in the US they wanted to not pay black workers after the civil war. So they started tipping.
It is, and always has been, nothing more than an excuse to not pay people properly.
|
72e424ff-61a6-4ff7-bb85-0201ba235c4d
|
bp7wpa
|
According to theories surrounding the big bang and specifically the moments afterwards, only a small, tiny percentage of matter would go on to form the stuff in the observable universe. What became of the missing majority of matter?
|
> The conservation of mass only holds approximately and is considered part of a series of assumptions coming from [classical mechanics](_URL_3_). The law has to be modified to comply with the laws of [quantum mechanics](_URL_1_)and [special relativity](_URL_7_) under the principle of [mass-energy equivalence](_URL_2_), which states that [energy](_URL_6_) and mass form one conserved quantity. For very energetic systems the conservation of mass-only is shown not to hold, as is the case in [nuclear reactions](_URL_5_) and particle-antiparticle [annihilation](_URL_0_) in [particle physics](_URL_4_).
Conservation of Mass is only a principle that applies approximately. It doesn't apply to particle-antiparticle annihilation. Normally particle-antiparticle annihilation doesn't factor in, which is why normally the conservation law typically applies.
|
0f0f8444-b339-45dc-9d1c-810c68d18fb6
|
bp7z0f
|
How are individual states able to make abortion illegal after the US Supreme court rulled that banning abortions was unconstitutional back in 1973..?
|
So this is less about them being able to and more about them getting to challenge the Supreme Court's decision in Roe v Wade.
Basically, these new laws are guaranteed to be challenged in federal court and will certainly make it all the way to the Supreme Court where these Republicans are hoping the conservative majority will choose to go against precedent and permit these extreme laws to go into effect. Short of holding a constitutional convention (which has lots of political risks for both sides) this is the only way for anti-choice conservatives to actually overcome Roe v Wade because Congress doesn't have the power to overrule the Supreme Court's ruling on constitutional subjects without changing the constitution itself.
|
9960194b-3196-4129-93d6-4e66fc44ecc9
|
bp8dy8
|
How do websites know to go to the mobile version on your phone even when you click a desktop link but don't know how to go to the desktop version on your desktop if you click a mobile link?
|
When you send a request for a website, you send information about your device and what exactly you are after in the headers of a request. There is a header called "user-agent" this basically defines what device you are on. Mine for example says "Mozilla/5.0 (Linux; Android 8.1.0; SM-T580) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.157 Safari/537.36". Therefore websites know that my device is an android device, so they know to deliver the mobile version to my device.
|
a1b7c613-0502-4649-b18c-72113ddeb44c
|
bp8ix7
|
. Is it possible to hack into a self driving car and change its destination/reck it ?
|
Sure is. Any internet connect device is technically hackable. Good luck, it won't be easy.
In more words, there is really strong security on self driving cars for numerous reasons, namely safety. While possible to hack it, it's not practical, nor easy. Hacking is not like you see in the movies, this sort of hack would take a very long time and immense resources.
|
c4fe49e5-7314-416e-91d2-cde73aa2486f
|
bp8m0j
|
. Is it possible to hack into a self driving car and change its destination or even reck it ?
|
This is the very thing that some cybersecurity researchers at Georgia Tech are investigating and the answer appears to be "Yes". Although there haven't been any large scale attacks on them and self-driving cars themselves have not been deployed on any mass scale researchers are finding plenty of problems with GPS spoofing and Collision Avoidance Systems that can be exploited.
|
29fdc346-6ba7-4837-adcd-2713e0c2edf7
|
bp8qrd
|
What causes the feeling of anxiety in our stomach/lower chest?
|
That would be a function of the autonomic nervous system, physiologically speaking that is. Anxiety seems to use many of the same circuits involved in the flight or flight response.
|
6b6358c3-c03b-44ed-aedf-285320ff6433
|
bp8xul
|
How can plants get cancer?
|
AFAIK "Cancer" is just unrestricted cell growth that can eventually interfere with normal functions. Cells usually come with a built in off switch when they divide, that tells the cell to stop replicating after enough are formed. If that limiting factor is missing, the cell will replicate over and over without stopping as well as passing on the mutation to the created cells. This is what causes a tumor. While I cant say for certain I assume the same rules apply for plants and their cells, i.e. if a cell is mutated to be missing the limiting factor it could replicate until it interferes with the plant's functions.
|
b29cbe61-a681-4c46-b24e-85f42669a354
|
bp9as6
|
Why do video streaming websites like YouTube choose to support 60 FPS only for 720p and above?
|
The lower quality tiers are usually for people who have slow internet connection. 60fps would however need more data to be transferred so it'd be counter-intuitive to make the 480p and lower available with 60fps.
|
4d24971c-447c-420f-92a8-47c03c8215b8
|
bp9bi6
|
How is a full moon possible when the sun always hits it from an angle off axis of the Earth?
|
The Moon's orbit is actually on a slight tilt of 5.14 degrees from the plane on which Earth orbits the Sun. Usually, during a full moon, you can see the Moon from the light reaching it either above or below the Earth. On the odd occasion when the Moon actually lines up with Earth's orbit and passes through its shadow, you get a lunar eclipse.
|
e71c7e1f-0ad8-4d4c-91bc-601a76c5bcf0
|
bp9fyt
|
How does alcohol clean things like bacteria?
|
Not a biologist but alcohol permeates the cell membrane due to it's small molecular size and displaces or bonds with the water molecules inside the bacterium. Leaves the cell dehydrated and unable to live basically. More here: _URL_0_
|
9c558017-f488-4f22-9608-8eb680d95dd2
|
bp9j82
|
Moles. How do they form? And are there people who don't have any of them? Is it even possible to not have any birthmarks or moles at all?
|
Since no one is answering the second part of your question: yes, there are people without moles or birthmarks. There's nothing special to it though. They're random, harmless mutations that occur frequently. And sometimes they just don't happen. That's all there is to it.
|
8fbe7850-1d45-4b0d-bc43-f262470d5e63
|
bp9px6
|
How did we know about the existence of non-visible light if we can't see it?
|
I don't remember the exact details, but long ago before we knew, a guy was doing and experiment with white light passing through a prism. He seen them typical rainbow coming out of the prism, and was measuring the temperature of each color. He moved the thermometer past the red spectrum of light, to where there was no color and the thermometer showed hotter then when in one of the colors. At that moment, infrared was discovered to exist.
|
5797cd75-bf95-4891-b660-229108c4044c
|
bp9zjj
|
How do certain hairs on our body know not to exceed a certain length?
|
They don't. They're hairs. Hairs don't know anything. They just get produced by special cells in your pores.
These cells operate in two cycles. The first cycle lasts a long time. In it it produces more hair, causing the follicle to grow in length. During this time it holds on tight to the follicle as it adds more molecules to the chain.
The second cycle is relatively short. The cell stops producing the molecules and releases the follicle from its production line. During this time the follicle is much more likely to fallout or be pulled or rubbed off.
The reason hairs only seem to reach certain lengths is because those links are directly proportional to the amount of time those cells spend in their production cycle.
EDIT: There's actually 3 phases. Anagen, the growth phase. The Catagen and Telogen phases map to the "Second cycle" i mentioned.
|
6abba91b-a37d-440c-be8e-39110802fd19
|
bpa5yi
|
Why are modern printers still so prone to errors? Why can the same color be so different on the same page?
|
Because the « color mix » is not the same. A printer use Yellow-Blue-Pink and a monitor use Red-Blue-Green.
The Printed image colors comes from reflected light and the Monitor ones from emited light.
|
21364b07-30ff-4c3f-8973-b924d8d30699
|
bpa64x
|
How can airport security scanners detect certain things, rather than just metal? How can it determine the difference between a gun and a watch if they're both made of metal?
|
Are you confusing an X-ray and a metal detector?
A metal detector will be set off by anything metallic, your keys, change, laptop or a gun. It doesn’t really scan for things.
A X-ray will show you the contents of a bag, and you can (sort of) visually distinguish each item
|
7ce5654d-16ee-4444-b66c-1a08cb195eae
|
bpae1n
|
why is kool aid powder sour before sugar is added to it as opposed to other drink powders that already have sugar added to them (crystal light, country time lemonade, tang, etc)
|
I can't speak for all of them, but Crystal Light and Tang use artificial sweeteners, which are stated to be 300-600x as intense as the equivalent amount of sugar. If you consume them outright, its too sour, but when diluted its sweet.
One way to think of it is like table salt. In a moderate amount it adds a lot of flavor to the food, but too much and it tastes bitter and feels like you are burning your tongue.
|
c735918f-8fe9-4a63-9b49-1cbb291ae554
|
bpav5i
|
Why do some countries want to leave the EU?
|
There are a lot of different motivations, and not all supporters of leaving hold all of them. I'll list a few below.
Freedom of Movement: Predominantly a British issue, the EU mandates that every citizen of the EU has the right to live, work, study etc in other countries of the EU. This has caused some issues, in the UK a number of people are unhappy with the level of migration from Eastern Europe to the UK. Thus they want to leave the EU.
Soverignity: One primary EU goal is "ever closer union" - essentially its slow transformation into a federal country like the US. Some people don't feel European, and thus don't want to be part of this federal Europe, and feel leaving is the only way to stop it. For example, they might want "their own government" to decide on regulations - because they do not feel like the EU is "their own".
Democracy: The EU has some issues with democracy. Its executive is not directly elected and a lot of power is held by various unelected officals through its institutions. A lot of power is also organised through countries within Europe, so rather than power being held by its citizens it is held by the German Chancellor or the British PM etc. Some don't feel that the EU is sufficently democractic, and don't think it can be reformed to be democratic, and so want to leave. Arguments on the nature of power are difficult to ELI5, since they are heavily linked to both how the EU is organised, how it actually works (i.e. including backroom deals and so on) and more philosphical arguments about democracy.
The Euro: This does not apply to the UK, except through the paranioa they might be forced to join. However it is a motivator for some continental views. Simply put, the Euro is not very stable. It links together economies that are very different, without strong safeguards. During the 2008 recession this had a devastating effect, causing a massive recession in poorer countries like Greece, and dropping much of the rest of Europe into a recession in 2010. Under the Euro southern Europe has struggled to grow, with a number of countries having not grown much since they joined. Whether this is the Euro's fault, if it can or will be fixed, and so on, are still debated. However for those who think the Euro is a problem, there is no legal way out, so leaving seems the only solution for some.
Trade: Being part of the EU removes a nation's ability to set its own trade policy - it cannot negotiate its own deals or set its own tarrifs or subsidies. Sometimes this results in deals not totally in a nation's favour. For example a country without significant agriculture might see the EU push for protection for farmers, which pushes its food prices up to protect another country's farms. Often disagreements within the EU causes deals to fail as well. Some people think that being outside the EU will allow for more trade deals, and for those deals to be better focused on that nation's interests, and thus want to leave.
Money: The EU collects money and pays it back out (like all governments). Some nations pay more than they directly receive, and thus some of their citizens feel they could save money by leaving.
Please note: These are motivations, not watertight arguments. You may see flaws in them, they may not meet your values at all (e.g. you might not care about immigration). This does not matter - what matters is that people belive them, and that people care about them, and that makes them want to leave the EU. I have probably missed some arguments. I have deliberatly ignored counter arguments since a balanced, nuanced, and in depth perspective would fill books. Also I do not agree with all of them, so would rather clarify than defend them.
|
0958efa7-9a09-498b-aa41-ce7bb642e6a1
|
bpb8dm
|
How did lightning turn the house lights on
|
I can think of two possibilities with the limited details provided. The first is that the power was out and it was forgotten that the light was turned on. Someone may have flipped the switch during the night after you went to sleep, which is why you didn't know about it. It was just coincidence it came back on then.
The other possibility is that the mechanical part of your switch is in very, very bad shape and the reverberations of thunder were enough to toggle it just enough to create a path for electricity. If that's the case, it's a massive fire hazard.
|
7cfa2c6b-5f83-4c9d-8b82-42117fb67e69
|
bpbfjp
|
Do memories get destroyed overtime or are they still locked away in your brain inaccessible? Would there be a way to access said memories?
|
A memory is a reflex, but instead of moving muscle, it's a brain path for an idea/feeling. If you can recreate that reflex, you should be able to remember something. As you acquire experience, these reflexes seem less and less unique, making memory retrieval difficult with age: like how a catching reflex is the same for any hand-ball sport, so it's difficult to remember every single time you caught something. Some people have incredible memory, usually by building a strong meaning or story for these different reflexes. Anyone can conciously train this, and some do it subconsciously. To sum up, some memories fade into a blur, while theoretically they could be accessed or partially salvaged by activating the specific reflex. Conciously, playing word association can retrieve a memory as you manually turn on paths near the specific path for that thought.
|
296e11c2-ad3f-4980-8aee-c6ed968cf200
|
bpbilx
|
Sattelite network, how many users can a single sattelite service?
|
Its not.
Satellite bandwidth is VERY expensive and used for places where its not practical to have a wired or wireless connection,
Isolated villages in south america or Africa, ships, places where infrastructure is non existent.
Plus its very limited.
Currently there are 4 major satellite communications Types for data.
Inmarsat/irridium - Used for Telephony and very slow data lines, the satellites are not geostationary so you have to keep tracking its position with your antenna.
C band - data connections for stationary systems, decent bandwidth and power. Geostationary satellites
Ku/Ka band - Same as C band but with smaller antennas and usually used for naval and moving installations.
BGAN - when you see a reporter with a flat square satellite receptor and shitty video quality ? thats BGAN, its basically improved iridium but with geostationary satellites.
now satellite bandwidth is very limited, becuase each satellite you put in orbit can provide a limit amount, and not only is the launch expensive, but also you have to have orbital slots which specify the coverage of the satellite.
The amount of users depends on the size of the satellite, the amount of transceivers its been equip with and how they have been distributed. you have to decide very carefully how much of the bandwidth is going to be TV, Data, Phone, and at what bands.
Also geostationary satellites are around 38k KM even at the pure speed of light in a vacuum thats around 300ms,
And then you have to take in to account alignment, if its co polar or cross polar, weather because clouds, rain and snow will introduce interference, Latitude becuase if angle of elevation for the dish is below 15 degrees radiation from earth or sea will interfere...
Vsat is a lovely technology, almost as reliable as carrier pigeons.
|
afdbebb1-61df-48ad-af75-b385b6cdc95d
|
bpbp8f
|
What is the difference between a carburated and fuel injection engine
|
Carburated is basically fuel getting into the engine by vacuum from the intake which is a gravity type system since it doesnt work when your upside down and needs about 2-3psi to work and a fuel injected system has electric solenoid injectors that open precisely at the right time to spray fuel right before the intake valve and the fuel lines are pressurised at about 60 psi. Then there is direct injection system where they spray fuel directly into the combustion chamber of the engine and this system runs at about 20000psi+.
|
676aeb75-a69c-43f8-86fe-0c5468f1caf9
|
bpbsr8
|
How do we know, that there is no solid ground on Saturn?
|
There is a solid core in there somewhere, but it's not very big compared to the volume of the planet.
We know Saturn is largely gaseous because it's less dense than water, a situation that's only possible if almost the entire volume of the planet is gas.
You can measure the gravitational force of the planet from the orbits of its moons, and that gives you the mass. Divide by the volume and you get a density number that's not possible for a planet with much solid or liquid mass. Earth is more than eight times the density of Saturn.
|
261fa3a6-179b-478d-9283-cbf9b66dbcdb
|
bpbwf7
|
. Why is there a Soho area in so many countries?
|
The original one is in London. The others are references to that one.
_URL_0_
> The Soho name has been reused by other entertainment and restaurant districts such as the Soho, Hong Kong entertainment zone[4] and the cultural and commercial area of Soho in Málaga.[5] The New York City neighborhood of SoHo, Manhattan, gets its name from its location South of Houston Street, but is also a reference to London's Soho.[6]
|
2111a4cd-ee90-47d5-8ef2-f607d80443b3
|
bpc0nj
|
How do big cars end up in malls?
|
It’s generally not overtly visible to the public, because they are a bit of eyesores, but places like these all have one or more large bay doors for the purpose of moving in/out large objects and vehicles.
|
37812a13-1212-42eb-a9bf-8c23fcaa04b8
|
bpc1h1
|
Home buying terms
|
> What are points and origination fees?
The origination fee is like an upfront payment to the lender for creating the loan. It is usually a percentage (0.5%, 1%) of the loan amount. _URL_1_
> Is earnest money basically just a deposit? Does it get factored into the sale at all?
This is also called "good faith" money. It is like a deposit - it shows that you and the seller have taken the first step to put the house under contract, that you intend to buy the house (pending any serious findings from an inspection), etc. If you go through with the sale, then that money will go towards the final cost of the house, like part of an early deposit. If you as a buyer do not go through with the purchase because the inspection found a ton of mold or meth damage that wasn't previously disclosed (or other previously non-disclosed issues) then you should be entitled to the money back. If you do not go through with the purchase because you got cold feet/changed your mind, then you would not get the money back. If the seller changes his/her mind then you would get the money back.
> What is a short sell and why do lenders ask if a house is a short sell?
A short *sale* usually happens when the seller is having financial problems and the house is about to be foreclosed. They are trying to sell the house for less money than what their current loan amount for it is (for instance, they might owe $200,000 still but are trying to sell it for $160,000). Or it could be when the property of the value has fallen lower than what the owner owes and the loan holder might recover *some* money from the sale of the house in its current state.
It just requires more paperwork and more agreements on everyone's part to get a short sale through, since the bank that owns the title on the house has to agree to sell it at a loss basically.
I would also caution you about short sales and just advise you to assume the worst possible scenario, which is that the person couldn't make financial payments, which means they probably couldn't pay to keep the house up so there might be some serious problems that you'll want to check for during an inspection (and some problems might even be self-evident when you do the initial walkthrough).
> Is the interest rate different than the APR? If so, how are they different? If not, why are both terms used interchangeably?
APR = annual percentage rate, it is the more technical term for "interest rate". They're used interchangeably because they're equally common terms for the same thing. Sort of like how someone might say "soda" and someone might say "pop", or "gas" and "fuel".
> What is mortgage insurance and what is covered by it?
Also called "Private Mortgage Insurance" or "PMI". It's generally activated when a buyer does not put down at least 20% deposit off the purchase cost. It's basically a way to protect the lender and help ensure the lender's investment in you is covered in case you stop paying the mortgage / fall behind on your payments. Some loans require it by default, others don't. You can read more about it here: _URL_0_
> What happens in the time between going under contract and when you close?
If the loan isn't secured yet (ie, you were pre-approved so you could make the offer but the loan wasn't fully processed), they would fully process it. You would have licensed home inspectors come and check everything for issues (make sure the outlets work, make sure the appliances work, make sure the air conditioning and heat work, check for structural damage, make sure there aren't any gas leaks or unmitigated radon risks, stuff like that); once these inspections are done you get a report of the issues, and you can even go negotiate with the seller to get some of them fixed as part of a bargaining tool. You'll get homeowner's insurance set up. You can pay to get the title of the property inspected and secured so you don't have someone trying to make a claim against you ten years down the road that the property is part of their great-great-great-grandfather's inheritance that they just received. Stuff like that.
**Since it's your first time buying a house, do research online about what benefits your state might offer you**. In some states there are first time home buyer benefits you can get access to that can help alleviate a little bit of the cost or grant you access to certain loans with better benefits.
edit: If you live in Maryland I know a great guy > _ > I don't want to advertise here, PM me but this agent hooked me up with one of the hardest working lenders and insurance agents I'll probably ever meet.
|
c5a075f3-8233-4bbc-a2c6-599800304d7a
|
bpc40m
|
Why are sour sweets/candy typically covered in sour sugar rather than the sourness being part of the sweet/candy itself?
|
So you feel the sour thing but the sweet stays in your mouth in the long term
Most people prefer the shock of sour rather than having a sour taste in your mouth for an hour
|
19eec4bd-ba3b-4fbc-93bf-8b38cec07472
|
bpc8ar
|
Why does the touchscreen of my phone not work if my fingers or display are wet, e.g. from rain?
|
Most modern touch screens use electrical sensors to detect where your finger is touching the screen. Water, a better conductor than skin, throws off that process.
Some old touch screens relied on detecting places on the screen where physical pressure was applied by sending where light was being disrupted, and hence water would have no affect on them.
At least that's how I remember it.
|
1c1d937f-abcb-4263-bca5-a9ec8bb4e083
|
bpcbxk
|
Why are some vaccines (like HepB) broken down into multiple parts?
|
What do you mean multiple parts? If you mean a series, it's because the HBV vaccine is not particularly effective at inducing long-term immunity.
The HBV vaccine works by injecting you with protein from the surface of the virus. Your immune system recognizes this protein as foreign and develops antibodies to it. The effectiveness of the vaccine (some months after injection) can be measured by counting the number of antibodies binding this surface protein per unit volume of blood (the usual units are IU/ml, where IU is "international units").
For the HBV vaccine, a single injection has a very low response rate. In other words, ~3-6 months after a single injection most people do not have a good circulating antibody count to the HBV surface protein. A series of doses dramatically improves the response rate. Some people may take 4 or more doses to get a good response.
This just varies by the virus. For influenza, for example, injecting a portion of the virus has a very high response rate after a single dose (over 70%). Inoculating with live influenza virus (an attenuated vaccine) is nearly a 100% response rate with a single dose. HBV is just a little harder to vaccinate, so you need a series of doses.
|
39014341-b75b-4e8c-b3d2-53956ef94f54
|
bpce9p
|
What causes the feeling of not knowing if something is extremely hot or cold when you accidentally touch a cold part of the shower heat controller when you're under a hot shower?
|
Your skin has things called thermoreceptors. There are hot thermoreceptors, which react best between 85F-105F and cold thermoreceptors which react best between \~65F-85F. At the extremes of these temps you feel pain, so really really cold can hurt just like really really hot. As well, some chemicals like menthol can set off cold receptors, and the chemical in chili peppers, capsaicin, can set off the hot ones.
& #x200B;
What you are describing sounds like what we call Paradoxical Cold. And to be fair, it's a confusing one. Some researchers think it's because extreme hot receptors are on the same fiber as cold. And we have seen that temps above \~110F can fire cold receptors, for whatever reason. There are more cold than hot receptors, Cold receptors are known to send signals 10 times faster than hot receptors to the brain.
& #x200B;
But the bottom line from doctors (me) and any literature I have read: We are still learning why...
|
6b428e6e-cafc-4cdc-a5a4-3a30b6dc4759
|
bpcf5c
|
What Happens When A Skyscraper Needs To Be Demolished
|
It's almost an art. [_URL_0_](_URL_0_)
Most high, but not too high skyscrapers are just blown up in such a way that it just falls down into one pile at the center of the building, and it's done by firstly partially destructing it's structural integrity but not too much, so it still could stand. Then major support beams are blown up from bottom to top and all floors are just falls all together.
Huge skyscrapers in dense area are removed every one in it's own different manner. At link above you can see one that was removed floor by floor from bottom to top without destruction of it's supporting beams.
Some removed manually top to bottom, just like construction in reverse.
|
6f411eef-bf38-414a-aa04-9ed6728d0002
|
bpcpyi
|
- Keyboards... Why are the keys arranged in that order? Is it cause of effectiveness? Wouldnt it be easier if the keys were alphabetically arranged?
|
Before computers, old style typewriters used little hammers to make the letter on the paper. The keys were arranged so the letters typed most often were spread apart so the hammers had very little chance of hitting each other and getting stuck. There is a keyboard style called Dvorak that is designed around efficient typing.
|
daa58009-826a-427b-8098-8faf7998ce56
|
bpd5uk
|
How come when lightning strikes the water (a lake for example) it doesn’t electrocute all the fish?
|
Waster is a good conductor, which means that the electrical current from the lightening is able to travel over the surface rather than go underneath. Same way a Faraday cage protects things inside. Most fish don't surface that often so they're generally safe under the water. Unlike humans that need to surface frequently to breath.
|
ff01e218-23a3-4a44-9b2b-aade8c727d70
|
bpdelz
|
is there a scientific rationale for 'Sleeping on It' when making decisions? Like, literal sleep helping to make better choices, not just more time to think on it
|
Because decisions are skewed when you’re highly emotional. You sleep on it, you let the emotions die down and you think with more clarity and logic
|
335d4150-d7d9-4ad9-ac7f-22cb7d168f35
|
bpdyti
|
What causes my earbuds' volume to lower whenever I yawn or stretch while wearing them?
|
The volume coming out of the earbuds doesn't change, but your perception of it does. Both of those actions involve your body changing the ear canal, which can cause sounds to sound different. Possibly the seal between your ear and the earbud is broken, leading to escaping sound. Possibly it's a change in the pressure in your ear caused by manipulating the Eustachian tube or the eardrum itself, which causes the eardrum to vibrate a bit differently. There could be numerous reasons why sounds are different during those two actions.
|
70914c27-33ac-4e46-8175-feeca754012d
|
bpdz9h
|
What's the real difference between tanned skin and freckles? And is it possible for someone to get so many freckles, that they eventually completely cover the skin and the person just looks tanned?
|
My grandpa had so many freckles he looked tan :)
Freckles are clusters of melanin in the skin. Tans are when your skin produces more melanin because of exposure to ultraviolet rays.
You can naturally have freckles, you can’t naturally have a tan. Tanning will always on some level be harmful for your skin and lead to an increased risk of things like cancer.
|
a193f274-c5ca-43f7-b419-e13287f7c6a9
|
bpdzfd
|
What causes the feeling of weakness in strength when seeing something such as blood or a video of a surgical operation?
|
It's the blood draining from your head because your blood pressure suddenly dropped, making you feel nauseous and need to lay down to get blood back into your head. It's a safety mechanism, kind of like a possum playing dead when something dangerous happens because predators prefer fresh meat.
|
cc310793-48be-4d74-a606-a63bb087a86e
|
bpe898
|
5G. What it is exactly and why it’s controversial
|
It was in the news that 5G will mess with weather satellite transmissions in the US. Not sure if that's what you mean.
But the ELI5 for that is simply 5G internet and weather satellites will be using the same frequencies.
I have to be honest that I don't understand the issue because it seems entirely avoidable.
|
5f11dc9c-851c-4ceb-b6f1-5faf0c885aaa
|
bpec6o
|
If warm air rises, why does the air become colder the higher in altitude you go?
|
There is less of it.
Think of temperature as a measurement of how excited the particles around you are, if there are no particles around you to be excited, it is "colder" (this is why ice is solid and steam is so dynamic).
In higher altitudes, there are less air particles and they are farther apart. This means that the same level of excitement for each particle doesn't register as the same amount of heat, especially since one particle can't excite as many other neighboring particles as it could in lower altitudes.
|
9e686237-c78d-4a0d-a1c9-ef95a865d89b
|
bped6c
|
With the recent news of the possibility of launching 11,943 satellites into low earth orbit for the Starlink Plan, how do the satellites not crash into others already in space as well as the recently launched ones?
|
Every time you put something in space it follows a carefully calculated and variable-scrubbed path. Barring extreme malfunction there's almost nothing that could move it around once it's in space. Plus space is massive so everything is far apart
|
5cc893c7-96dc-4e19-8afc-ad0c32329ae2
|
bpeihs
|
water conducts electricity, how far can that electricity travel and still be dangerous? If an electrical cable is in the ocean how far do you have to be to not get shocked?
|
It depends on lots of things:
* The voltage on the cable
* The precise chemical makeup of the water the cable is in
* If there is a low resistance pathway in the water, or one that leads out of the water.
Electricity is dangerous and should be respected. Never get in the water if you believe there is a live electrical cable in it as well.
|
e7b447db-4e5d-4882-9b47-eb7c852879b8
|
bpekqd
|
What are physical unclonable functions?
|
I haven't heard of this, but I'll guess based on things I know, and the context you provided. Hopefully someone can give a better answer.
I'd assume they are a result of the the doping (intentional introduction of impurities, which helps control certain properties) in semiconductors. While this is controlled to an extent, I don't think they can determine the placement of impurities at a microscopic level, so it is kinda randomized, so when a signal passes through it, it has that unique "digital fingerprint" you mentioned. Probably too small to see. If I'm right about what this is, it probably isn't intentional, but someone figured out that it exists, and how to use it as a digital fingerprint.
|
9d8b7629-00fe-4929-aeb9-6e8e1c03e39e
|
bpew27
|
Why did the look of movies get "clearer" in the 1990s?
|
The quality of film has evolved over time. We've learned to make film that doesn't crush black as much. Early black and white movies don't look nearly as good as later black and white movies. The color process has evolved too, allowing far more nuanced shades of colors. But we've also learned how to make film with finer crystals, which makes for a smoother look and more detail even on the same size of film.
I don't think the difference you're seeing between movies this relatively recent and this relatively close together has much to do with a noticeable advancement of technology, however. There are many many different types of film to film on. Even film by the same company can vary quite wildly in terms of color, contrast and grain. Choosing the right film for a project is an artistic decision.
License to Kill is a movie where Timothy Dalton wanted to return the character of James Bond to be more grounded, believable, and ruthless. Closer to how he felt the character was developed in the books. For a Bond movie, it's extremely serious. It would make sense to pick a grainier type of film for a grittier movie.
The World is Not Enough is a very campy movie that it doesn't take itself seriously. It wouldn't benefit from a gritty filming style.
|
a358c7a6-d1b8-47f3-8e2c-6d97ce301a83
|
bpexvx
|
Why aren't amendments made to religious books to keep up with growing times like they are to the Constitution and Government documents?
|
Religious texts (books) are seen as the word of the god or prophet that wrote them. Because of that, they are not supposed to be rewritten or reworded.
In a way, we have seen "amendments" to the Bible, though. There was the Old Testament, and then the New Testament that was created as an "addition of revelations from God".
Ultimately though religious people can't just change or add to a religious text, so they change how the text is interpreted to suit their world view or sometimes to adopt new scientific discovery.
|
a43969f1-f35e-434b-9e24-f8c9932237aa
|
bpeyst
|
What do Chinese economists argue are the benefits of not floating the Renminbi without restrictions?
|
Well, realistically, Chinese economists don't "argue" anything. The government has set the rule that this is the case, with the goal being to artificially keep the currency lower value to increase exports. The low currency allows China to maintain a strong position in the world market for exports, and keep their costs low overall to operate businesses in China.
This comes at the negative effects of people being paid in renminbi (i.e. Chinese people), but China straight up doesn't give a F about their people and are more concerned with growing China's market and economy overall and getting a dominant position for export goods, at nearly any cost. And obviously being in China, those who may question this tactic just sorta disappear.
|
6fd661ad-6434-4b95-a181-1dba5a37118f
|
bpf2tt
|
Nuclear Power Plants and how they make radiation
|
The "fuel" used in power plants is itself radioactive. Inside the power plant, they make a controlled chain reaction by inserting rods made of certain materials into the fuel (like uranium). This chain reaction makes a lot of heat (that is used to make the power), and it also transforms the original fuel and elements used into other elements that are also radioactive.
It's a similar idea as to how a nuclear bomb works, except the nuclear bomb's reaction is not controlled, while the nuclear power plant's reaction *is* controlled. When it loses control, the reaction can accelerate, producing more energy and more heat and producing more radioactive elements into places where they're not supposed to go.
|
c08ff0ab-3069-473a-b6c5-9b7278e8023c
|
bpf3q1
|
How does the body know when to stop growing?
|
In the sense of height, most of our bones (especially the long bones in the arms and legs) have growth plates. These are near the ends of the bones (picture them being right before where the bones bulge out into your joints). As the name implies, the bones grow from these areas. The growth plates get smaller over time, and once they're gone, the bones no longer grow longer. How long this takes to happen, and how fast the bones grow before it does, is due to genetics and things like nutrition
|
a8724964-a5ca-4f9e-8e91-479017cf396f
|
bpf87h
|
When a car accelerates, why do the wheels appear to slow down then go in the opposite direction?
|
I assume you mean in videos. It's the frame rate of the camera making them appear to slow down and go in reverse.
|
63f76f86-2fc7-43b4-b3b8-8a005eb22111
|
bpfgxf
|
How does Costco's brand 'Kirkland Signature' manage to make everything from food to clothing?
|
Short answer: they don't!
Long answer: This is something called Private Labeling. Costco contracts with existing manufacturers of these products and has them put their labels on the product. Kirkland Signature soups might be Campbell's, which Kirkland Signature jeans might be Levi's - but they're branded as Kirkland Signature. They can also potentially be produced by a company that specifically works with private label brands - it's not the same product as the name brand, but a similar one.
Costs are generally lower for store-brand private label because there's no advertising costs included in them - Costco doesn't advertise Kirkland Signature, they just advertise Costco.
_URL_0_
|
02575a41-cf0c-4960-bc5d-06cdb85b2d0c
|
bpfib3
|
How did the world's first spoken language came into existence?
|
Language was likely developed when people used certain sounds to alert one another of specific things. Overtime these were taught as essential for fast communication.
I doubt language started out with complex sounds like in today's modern languages, however they likely started as small and quick sounds. Of course, as they developed, they got more and more complex.
|
e6292fd6-2e1e-4abb-a5c1-b468a0f01393
|
bpfokc
|
Considering conservatives have the highest rates of obesity, why is personal responsibility a cornerstone of their politics?
|
This might not be the sub for this. Not sure what sub it would be, but this is still kinda loaded, even if you're being genuine, which I believe you are.
|
0d4be995-ed34-4e63-af01-20a89620e84b
|
bpfxkk
|
What is affiliate marketing and how does it work exactly?
|
Affiliate marketing is where you get paid a commission for any sales you refer to a site selling goods (provided they have an affiliate program you are signed up for).
Imagine you have a travel blog and write a post with your recommendations for best suitcase, camera, walking shoes, travel gear, backup phone battery, etc. Now, you could sign up with an eCommerce site as an affiliate and link to those products on their site and whenever somebody reads your article and clicks over to buy that item, you get a commission.
Or maybe you have a site where you rate drones, and link to a site that sells drones with each review.
|
cfc6c015-575a-46d0-b5ff-619dee705249
|
bpg1iy
|
Why do humans breath oxygen while for plants it's waste?
|
No one has said this yet so I will add: plants use oxygen too. They have mitochondria just like us. While plants do make CO2, light, and water into sugar and oxygen, they also need to digest that sugar into food to actually use they energy. They create and expel oxygen not as a waste product, as plants also need it, but as excess. During daylight hours, photosynthesis creates more sugar and oxygen that plants can use as fuel.
This may not exactly answer the question but I hope it fills in some of the gaps
|
63df1eb0-77a0-4055-811b-eba7662b71ad
|
bpg40l
|
How to they remove the caffeine from tea and coffee?
|
One way is using liquid carbon dioxide to dissolve the caffeine away while leaving the flavored compounds mostly alone.
Another way is to wash the product in a saturated mixture of the coffee or tea from which the caffeine has been removed from using things like charcoal filters. As there is now no caffeine in the fluid but there is in the product, it tends to seep out into the fluid to equalize while the original flavoring compounds stay in.
|
8225ff5e-e1d4-47e9-8150-6e7d3057d4d3
|
bpgse6
|
Native American singing
|
The lyrics can be made of actual native words and “vocables” which are sounds that used to be words, but their meanings have been lost. Kinda like when you’re singing along in the car and don’t know the words, so you mumble something that sounds like what they said, but isn’t actually a real word (and you don’t know the real word). I shouldn’t have to say it, but of course all the songs are always about *something*, usually interal to the culture.
Then there’s the rhythm, drums are sometimes *intentionally* played off-beat. So the singing might be at 150 bpm, but the drums might be at 140 bpm. IMO it gives a spiritual feeling to it, as the drums and vocals sync and de-sync, but it’s hard to put your finger on why without knowing the beats are off. It’s also pretty difficult to sing at one tempo but play at another, so it’s a display of skill. Kicking that up a notch is playing and singing with a group and everyone staying on both tempos.
Then there’s the flute songs, which are usually improvised. IIRC, it’s meant to capture the player’s feelings right at that moment. A tradition I heard about was someone would carve a flute after they proposed to someone, and then would play a solo during the union/wedding ceremony.
This is all stuff I remember from a Musics of the World 101 class, so obviously I’m not an expert haha. It was just really interesting to me.
|
cd2d6f32-f44f-4dbd-a8c3-3c501891122c
|
bpgsmv
|
What is that burning in our nose we feel randomly?
|
The capillaries in your mucus membranes are being dilated quickly bringing blood to that area faster than normal. This stimulates the nerves close by.
|
b973d07c-f93e-4195-97b8-028c03a78079
|
bph1xn
|
Is it okay for companies like spaceX to just send junk like cars and 12 thousand satellites into orbit, won't that create a ton of dangerous garbage in space?
|
The satellites aren't junk or garbage. They have a purpose, they are the kind of thing we want.
But, most importantly, these are controlled, trackable orbits. This is key because space is /big/ so we can dance thousands of satellites through the various orbits. Because these satellites are less than pebbles and operating in formations across three dimensions and different types of orbits.
The car? It's orbit intersects with the earth. Oh, and also Mars. It's over a trillion miles away from us, at the moment. If something went wrong in the future? It'd burn up in the upper atmosphere if it didn't just fly out into the black.
|
f41ebf4c-8737-4062-8a04-dfa907ce3b58
|
bph8zd
|
Roe V Wade
|
> Although, this would allow banning abortion, wouldn't revoking Roe V Wade potentially allow the government to have a say on what surgeries I can and cannot receive?
Abortion **is** a surgery that people want the government to say whether you can or cannot receive.
Don't separate one medical procedure from another just because it's been politicized beyond all reason.
|
f39fb2f7-f84e-4558-b1bc-0946ed02b5aa
|
bph99y
|
The universe is a 3D space, yet our planets are aligned on a 2D plane. Why?
|
At the beginning our proto-solar system was just a cloud of gas and dust. As gravity make these particles of gas and dust attract each other the cloud will get smaller and smaller.
& #x200B;
This cloud have a tiny spin. Each individual particle was going in a random direction, but the overall cloud have a preferred spin. Basically, the direction of the majority of particle will become the preferred direction of the spin.
& #x200B;
Angular momentum stay the same, so as the spinning cloud become smaller, it spin faster. Now think about a pizza dough. When you spin it, it flatten and that's because the spinning put a force on the dough. It's the same with the spinning cloud, it flatten more or so on the alignment of the spinning axis of the cloud. As time pass, more and more of the outlier (those particle that spin in another direction or axis) get eliminated. Either because they collided with something else, or because the gravity of a bigger mass grabbed them.
|
b1c97c72-7883-4025-9034-5943f328df53
|
bpha5o
|
How close do you have to be to a car to benefit from "drafting". Can you get better gas mileage while still keeping a good distance?
|
It depends on the aerodynamics of the cars involved. Pull your minivan a couple car lengths behind a semi-trailer, you'll feel the drafting effect.
If you have two fast cars with good aerodynamic coefficients, you need to be less than a foot apart.
|
1bef306a-f74f-4798-8a37-dfa981737ea1
|
bphe3u
|
Why do sirens and vehicles change pitch when they pass you?
|
it's called the doppler effect. the sound waves get smushed as they approach you, and stretched as the source of the sound moves away from you. this changes the pitch, because pitch is based on the size and frequency of the sound waves.
it works for light, too, but the object has to be moving pretty fast. that's how we know the universe is expanding.
|
eaf9db2a-8e6f-4e1d-a2cd-d29d6d24e491
|
bphejj
|
Why cant women from Alabama just go to other states for abortions? How would they enforce that?
|
They can, just as homosexual couples did with getting married in other states before the current case law. An issue, amongst other issues, is the burden this places on Alabama women, specifically women who cannot afford to travel to another state to have the procedure.
|
c7670385-76a6-4280-b514-40e5b8b6edab
|
bpho02
|
Where does wind come from?
|
the short answer is the sun.
& #x200B;
The earth's surface doesn't heat evenly. The sun sends radiant energy that hits the ground, and then the ground reflects it as infrared (heat). This makes the air get warm, which rises. So when that warm air rises, something has to rush in to replace it (colder air from somewhere else). That's wind.
|
63cb9181-41f7-494c-8c7a-8c350f96330c
|
bphqu8
|
Why and how do we get tongue blisters?
|
It sounds like you may be referring to a canker sore.
The precise cause of canker sores remains unclear, though researchers suspect that a combination of factors contributes to outbreaks, even in the same person.
Possible triggers for canker sores include:
& #x200B;
* A minor injury to your mouth from dental work, overzealous brushing, sports mishaps or an accidental cheek bite
* Toothpastes and mouth rinses containing sodium lauryl sulfate
* Food sensitivities, particularly to chocolate, coffee, strawberries, eggs, nuts, cheese, and spicy or acidic foods
* A diet lacking in vitamin B-12, zinc, folate (folic acid) or iron
* An allergic response to certain bacteria in your mouth
* Helicobacter pylori, the same bacteria that cause peptic ulcers
* Hormonal shifts during menstruation
* Emotional stress
Canker sores may also occur because of certain conditions and diseases, such as:
& #x200B;
* Celiac disease, a serious intestinal disorder caused by a sensitivity to gluten, a protein found in most grains
* Inflammatory bowel diseases, such as Crohn's disease and ulcerative colitis
* Behcet's disease, a rare disorder that causes inflammation throughout the body, including the mouth
* A faulty immune system that attacks healthy cells in your mouth instead of pathogens, such as viruses and bacteria
* HIV/AIDS, which suppresses the immune system
|
101f2791-8c8f-4f65-9630-5a2ca227c5bc
|
bpi2vr
|
Why don’t modern day Italians speak Latin?
|
Latin became several different languages, which we collectively call the "Romance Languages" today - Spanish, French, Portugese, Italian, Romanian, etc. It definitely didn't change uniformly in one direction - it changed in several different directions as areas that were formerly under Roman influence slowly developed separately from each other. Any groups that are divided from each other will eventually change the way that they speak, and modern Italian is just one of many directions in which that language evolved - although it happens to be the one they speak in the modern city of Rome.
On top of that, Italian isn't even really a single language! Tuscan, Sicilian, Corsican, Venetian, there are several languages in the Italian family that are distinctive enough to be considered their own languages that are still spoken today to some degree. Standard Italian, though, is spoken throughout the country and is generally considered the closest to Vulgar Latin. And of course, Vulgar (or common) Latin was a different version of the spoken language that developed among the Roman population well after the "Classical Latin" that was most commonly written and which many of us studied in school, so there isn't really one "Latin" either. No single language survives too long in history!
|
38be550a-ec5a-41a8-8916-adc45f6ca74f
|
bpi80r
|
how do specific birds know to use the birdhouses specifically for them?
|
They make the houses based on the needs and preferences of that particular species. That doesn’t mean other bird won’t use them, just that there’s a better chance a bird of that species will use it since it suits their needs best.
|
483cb851-c202-4dc7-a16c-c79019a08cab
|
bpimbu
|
Why does getting hit with a slap hurt differently than getting hit with a closed fist?
|
A slap with an open hand covers more surface area of your skin, and makes the skin think it’s been damaged or traumatized. Conversely a punch covers LESS surface area but often affects more than just the skin, which is why you can get a persistent pain from a punch (in the muscle beneath, even!). With a slap, it reddens the skin and might sting, but often doesn’t go beyond that.
Hope that helps!
|
1a4bca6f-f9fd-4f58-8389-e5dbe89873ff
|
bpioo0
|
How do road line painters get the markings exactly where they need to be? They always seem to be perfectly in the middle no matter how complex or uneven the road edges are.
|
Before the striping paint or thermoplastic is applied, a crew going out and layouts of the location for all the striping. This is called cattracking. It is small marks in white or black paint that serve as a guide for the painting machines. It will have the start and stop locations of each line and the alignment. For curves they will use a length of rope to match the curve, then cattrack along the rope.
Once that is approved the the local agency, they either install it with a small hand cart that the operator starts and stops by hand (_URL_0_)or for large road way jobs, they use a truck (_URL_1_).
Most of the catracking marking are then covered by the road paint or thermoplastic. You can sometimes see remnants where there are skip lines.
|
c9d78e5f-4c60-4606-80ce-4eb06cdcb625
|
bpiy8e
|
Why do camera sets have particularly green coloured curtains for CGI and VFX and not any other colour?
|
It is a color that is easy to exclude from the set. Red, yellow or brown might exclude skin tones or hair.
|
8a71855e-dbb6-46e9-b29e-f987135ef8a1
|
bpj0xs
|
What happens, physiologically, when one cracks their knuckles?
|
This was something of a medical mystery for centuries [until the invention of things like ultrasound imaging and high speed, high resolution MRI scanners](_URL_0_)
If a joint stays in the same position for several minutes, most of the sinovial fluid flows out of the gap between the two rubbery cartilage surfaces,( called the "Articular Cartilage.") This creates a seal between the two Articular surfaces.
Pulling on the joint in some way may temporarily lower the pressure between the two surfaces enough that it causes remaining fluid to boil at body temperature, creating small water vapor bubbles.
Eventually the seal is released and this causes the bubbles to collapse rapidly due to the rapid increase in pressure, as the water vapor reverts back into a liquid. These bubbles collapse violently creating a small shock wave.
It's common for people to be concerned that this might cause joint damage, but there's no firm evidence that cracking your knuckles leads to joint disease.
It's important to note that using something like a punching bag subjects joints to more severe punishment.
|
6571d90d-afcd-43d2-b0a5-4de0184428eb
|
bpj1st
|
How do printers work so accurately and fast?
|
I don’t know what exactly you are looking for as an answer...
They work accurately because the motor that controls the printing head works in very small increments (typically 96 positions per inch) and the ink injectors can inject extremely small quantities of ink.
They work fast because the motor is fast.
|
1caa7ea1-c699-4474-b072-00099175f84e
|
bpjc12
|
What does Microsoft and Sony teaming up for cloud gaming mean?
|
It means that it no longer matters if you buy ps or xbox and which ones your friend has. Games on both platforms can play together.
|
ca85c6fe-edc0-40af-a575-bc7ff35e8562
|
bpjkj3
|
How do countries pay other countries?
|
Usually private or (semi private) companies buy the oil, not the state directly. In this case they usually purchase the product on the world market entering a contract for delivery for a certain grade oil. (oil varies massively in types and grades).
The exchange of money is usually done on what is called the SWIFT network, which connects nearly all banks across the world. Once the contract is fulfilled, the final payment is transfered from whoever bought the oil to the oil company.
You can access this network at your local bank, but you need some pretty specific information before you can transfer money in this way.
Edit: think an email money transfer. But bigger, slightly safer and more expensive. I believe it's 25 or 30 per transfer? Been a few years for me.
|
3dfd4c76-9b65-4186-9856-9bad91baf718
|
bpjtnf
|
How does the body heal and repair during sleep?
|
Not a biologist or someone who really knows the answer, but the body is repairing itself all the time. When you are sleeping a lot of various processes and the energy for them are not being used so there is more energy that can be spent healing so you heal faster than if you are expending that energy being active
|
86e411dd-e8d9-456f-8e03-fc44d0ced4a5
|
bpk2bs
|
What happens to pest insects physiologically after having been sprayed with Raid or Black Flag, etc.?
|
Depends on the pesticide, but most of them are neurologically toxic and/or are desiccants. For the neurological pesticides, think nerve gas for bugs. For the desiccants, think rapid mummification.
|
8e4e18b9-5939-45f5-98e3-475746347c6f
|
bpkmzq
|
Why do cavities in teeth need to be drilled before being filled?
|
Cavities are drilled to remove the decay/rot from the tooth so the filling can be place on tooth structure that is healthy to prevent further (secondary) decay/rot.
Source: Me. I am an Expanded Duty Dental Assistant and this is literally my job.
|
20981912-623b-4c10-8fff-68fff2cd9396
|
bpkslw
|
How did humans all over come to know what parts of a plant are edible, toxic, and which ones serve as remedies for illnesses ?
|
Trial and error, and they were often wrong.
Many traditional plant remedies are total nonsense, or even actively harmful, and tomatoes were widely thought to be poison by most of Europe for hundreds of years.
|
f1bb86ec-251d-4a85-83be-59fcb35a19df
|
bpkuiu
|
why do hangovers get worse as we age?
|
Your body just doesn’t work as well and is less efficient with age. I think it’s somewhere in your mid 20s when you physically peak, and afterwards you are in a perpetual slow decline.
Specifically your liver and kidneys don’t work as well.
|
aedef674-4b69-49fb-b303-f98a978aa49c
|
bpkvmt
|
Didn't the Supreme Court rule that abortion was legal? What in the legal system allows for such varying definitions of legal abortion across state lines?
|
The supreme court ruled that under federal law no states shall outright ban abortion prior to 24 weeks. This ruling is Roe v Wade, which I'm sure you have heard of.
The purpose of the new state laws being pushed through is to trigger a supreme court retrial in hopes of changing the law. Now is the first time in recent history that there are more pro-life judges on the bench than there are pro-choice. As soon as someone challenges the new state law, which will happen, the supreme court can hear the case and will most likely reverse the Roe v Wade decision.
|
0a859e88-320c-4271-a73d-6dba4e880bfe
|
bpkx3m
|
what is perturbation theory?
|
So in physics it's usually like an additional term to a potential energy surface. What that means is it's where you take a possibly "perfect" model system and add something extra to it to try and account for differences between the model and reality. The something extra is called a perturbation. This sometimes leaves a bad taste in the mouth of purists cause you would want your model to be as realistic as possible in the first place and not need a perturbation.
So I assume there's a similar scheme in economics, create a model and then kind of pile on perturbations.
|
fc324363-1fd4-4dc4-b33c-6ba2a387f1a7
|
bpkxpa
|
What causes "good days" and "bad days" when you run/exercise?
|
Keep in mind there's a natural change of energy during the day while not exercising. If you sit on the train for an hour to get home from work, you probably feel very tired. If you talk to your friend about weekend plans, you probably get excited and have more energy.
There are factors like you mentioned. Other factors are hormones. For example, after you eat certain hormones are released in order to use the new energy. After a period of time, your blood sugar lowers and you may feel more tired. Adrenaline and other neurotransmitters affect your state drastically as well - part of why mental state affects your ability.
This is why routine is so important. It helps both your body and mind to have the proper "set up" for exercise. That's why athletes do the same thing on game days - like run/skate in the morning, lunch, afternoon nap, and then pre game routine and warm ups.
|
d445556a-7e7d-470f-8a1e-3a4f9b4c5883
|
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