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please explain the isis iraq situation. | Ohh man its complicated..
So ISIS is the Islamic State of Iraq and Syria. They have been active mainly in Syria fighting against Bashir Al Asad, but have been pushed back there (out of Alepo and denser urban areas) by more moderate rebels (who the US ostensibly supports). Recently they cashed in on the Iraq side of the... | [
"In early 2014, ISIL drove Iraqi government forces out of key cities in its Anbar campaign, which was followed by the capture of Mosul and the Sinjar massacre. The loss of control almost caused a collapse of the Iraqi government and prompted a renewal of US military action in Iraq. In Syria, ISIL has conducted grou... |
How do people determine the tilt of a planet of direction is relative in space? | We define the ecliptic as the plane that contains the Earths orbit around the sun. We define the tilt of a planet as the angle between the normal direction of the ecliptic and the axis of rotation of the planet. | [
"Orbital inclination is the angle between a planet's orbital plane and another plane of reference. For exoplanets, the inclination is usually stated with respect to an observer on Earth: the angle used is that between the normal to the planet's orbital plane and the line of sight from Earth to the star. Therefore, ... |
[Book Request] I don't see any books for the Reconquista on the book recommendation list | Point of clarification. What are you looking for when you say "a general history of *the Reconquista*?" Although the underlying crusade ideology is there for the Christians, and as time wore on Muslims definitely realized their al-Andalus (by then comprised of many little kingdoms) was losing ground to a bunch of Chris... | [
"A book has been published (written in Spanish) under the auspices of the Ajuntament De Carlet, Valencia, with the title \"Amparito Roca, El Pasadoble Del Mestre Texidor\". It contains biographical material and commentary on the works of Texidor with a catalogue and discography. The text is by Angel Valero Garcia.\... |
Why did CPUs stopped at around ~3-4GHz? | See:
_URL_0_
_URL_1_ | [
"Both the 6400 and 6600 CPUs had a cycle time of 100 ns (10MHz). Due to the serial nature of the 6400 CPU, its exact speed was heavily dependent on instruction mix, but generally around 1 MIPS. Floating-point additions were fairly fast at 11 clock cycles, however floating-point multiplication was very slow at 57 cl... |
What festivals did the romans celebrate (pre-christianity)? | The Romans celebrated plenty of festivals, and I'll highlight a couple of the more important ones for you.
* **Lupercalia:** This is possibly the most famous Roman festival, along with Saturnalia. It was celebrated during February (13-15) and it was a celebration of the health and fertility of the city of Rome. Prob... | [
"A major source for Roman holidays is Ovid's \"Fasti\", a poem that describes and provides origins for festivals from January to June at the time of Augustus. Because it ends with June, less is known about Roman festivals in the second half of the year, with the exception of the Saturnalia, a religious festival in ... |
why is if more harmful to the human body to be exposed to freezing water than it is to be exposed to air of a similar temperature? | Heat generally transfers from molecule to molecule. More molecules means faster heat transfer. The amount of molecules in a given volume is called density. Generally speaking, the denser a substance is, the better it is at transferring energy. Water is much denser than air. So, heat energy from your body will flow... | [
"Heat is lost much more quickly in water than in air. Thus, water temperatures that would be quite reasonable as outdoor air temperatures can lead to hypothermia in survivors, although this is not usually the direct clinical cause of death for those who are not rescued. A water temperature of can lead to death in a... |
How and when were tanks, semiautomatic weapons and planes started being deployed in warfare? | The Second Industrial Revolution happened.
Generally considered to have started in 1870, the Second Industrial Revolution saw the development of a wide range of technologies, manufacturing techniques and chemicals that made many of the weapons and technologies of the First World War possible.
More efficient means of ... | [
"In post-Cold War conflict, the resurgence of expeditionary warfare has seen the emergence of gun-armed wheeled vehicles, sometimes called \"protected gun systems\", which may bear a superficial resemblance to tank destroyers, but are employed as direct fire support units typically providing support in low intensit... |
what is modern art and what determines the price? | Whatever the artist feels he is owed is weighed against public appraisal. It’s supply and demand, but on a very intimate scale, that determines the price. That is to say, the worth of the piece is the highest value a person wishes to pay. If the artist accepts, then that will be the price at which it is sold. | [
"Components of a work of art, like raw stone, tubes of paint or unpainted canvas, in general have a value much lower than the finished products, such as a sculpture or a finished painting. Also, the amount of labour needed to produce an item does not explain the big price differences between works of art. It seems ... |
why is depression such a pervasive theme throughout reddit? | Reddit is a fairly liberal place that likes to focus on fighting for marginalized causes. Depression and mental health are largely ignored in general society and affect a huge number of people, so naturally Reddit wants to talk about it. Also, since Reddit is an anonymous community, it is much easier to talk about our ... | [
"In this way, the depression can be traced back to a demand for perfection from which a person is deducing their own worthlessness, from which they are in turn deducing the horribleness of what happened.\n",
"Scholars Dhir et al. discuss the potential for depression in relation to social media use and FOMO. They ... |
why are rabbits associated with sexual things like playboy? | Rabbits have a reputation of breeding prolifically, which leads to their reputation of having sex very often. | [
"Rabbits are often used as a symbol of fertility or rebirth, and have long been associated with spring and Easter as the Easter Bunny. The species' role as a prey animal with few defenses evokes vulnerability and innocence, and in folklore and modern children's stories, rabbits often appear as sympathetic character... |
difference between memory and ssd | Memory typically refers to RAM (random access memory) where as SSD (solid state drive) refers to storage.
Easiest way to know the difference is think of RAM as a work table and SSD or other storage device like a hard drive as storage cabinets.
If you want to work on a project, you can only use as many tools (aka app... | [
"While both memory cards and most SSDs use flash memory, they serve very different markets and purposes. Each has a number of different attributes which are optimized and adjusted to best meet the needs of particular users. Some of these characteristics include power consumption, performance, size, and reliability.... |
how does mass hysteria work and how can it manifest physical symptoms? | It's pretty much a huge case of fomo with the placebo effect. You see a bunch of people doing something and your mind thinks that the might be something triggering it that effects you so you begin to physically manifest something like an uncontrollable urge to dance or some kind of sickness | [
"In sociology and psychology, mass hysteria (also known as \"mass psychogenic illness\", \"collective hysteria\", \"group hysteria\", or \"collective obsessional behavior\") is a phenomenon that transmits collective illusions of threats, whether real or imaginary, through a population in society as a result of rumo... |
why does hard cheese which has been maturing for years have a sell-by date of only a few weeks? | It's been cut.
As long as the outside of the cheese is entirely the outside of the cheese (the rind), the cheese will have a substantial shelf life. As soon as you cut it, opening up the more moist interior to oxidation, mold, and bacteria, it has a shelf life. That being said, some cheese (like parmigiano reggiano) w... | [
"Harder cheeses have a lower moisture content than softer cheeses. They are generally packed into moulds under more pressure and aged for a longer time than the soft cheeses. Cheeses that are classified as semi-hard to hard include the familiar Cheddar, originating in the village of Cheddar in England but now used ... |
why is video ram (like gddr5) so much faster than regular ram (like ddr3 or ddr4)? | GDDR, similar to GPUs are very parallel in design.
So while you might have "dual channel" or "triple channel" memory slots on a system board, GDDR memory can be arranged into 8, 16, or 32 parallel channels on the graphics circuit board. This yields nearly linear performance gains in memory throughput since memory chip... | [
"BULLET::::- Clock Speeds: This is the clock speed that the graphics core and video RAM run at; they do not need to be the same. The faster the clock speed, the more the graphics core and/or video RAM can accomplish in a second. All modern video cards use DDR SDRAM, which, for all performance issues, is twice as fa... |
in david attenborough documentaries, how do they get the camera inside each respective insect/animals home? | If you have the DVD/Blu-Ray sets, watch the behind-the-scenes extras.
These nature photographers spend months and months working to catch the perfect moment (really makes the viewer marvel and appreciate their contributions to public knowledge). | [
"Several special filming techniques were devised to obtain some of the footage of rare and elusive animals. One cameraman spent hundreds of hours waiting for the fleeting moment when a rare frog, which incubates its young in its mouth, finally spat them out. Another built a replica of a mole rat burrow in a horizon... |
What is the price difference between geothermal energy and fossil fuel energy? | It really *really* depends on where you're trying to get geothermal energy from. In Iceland, which has tons of volcanic activity and gets all its electricity from geothermal, electricity prices are about half the cost in other Nordic countries.
However, in almost every other part of the world, you'd have to drill 5-1... | [
"Geothermal power is considered to be a sustainable, renewable source of energy because the heat extraction is small compared with the Earth's heat content. The greenhouse gas emissions of geothermal electric stations are on average 45 grams of carbon dioxide per kilowatt-hour of electricity, or less than 5 percent... |
Help identifying a Japanese battle flag from WWII | I can't read all of it--the vertical text on the sides is quite difficult and I will leave it to somebody else. But the text on the top 国報身 献、is a wartime slogan that means something like 'serve the country, give up one's body' and the name of the soldier on the bottom horizontal text, I think, is Hisanaga Takeshi. It ... | [
"BULLET::::- Finding the red in the national insignia adopted in June 1943 for its military aircraft could cause confusion with Japanese markings during combat, the United States adopts a new marking consisting of a white star centered in a blue circle flanked by white rectangles, with the entire insignia outlined ... |
how come the military is "always recruiting" and are all countries like this? | People are always leaving and moving up even when an army downsizes. Ergo there are always needs for replacements at the bottom.
Now you may not get to be a helicopter pilot. There is always need in the infantry | [
"The most popular age group to recruit for the military is the youth population, because many youth are opting out of going to college because of the economic times and financial positions. \"The recruiting process involves national and local advertising to efficiently supply information on a widespread basis; info... |
how do people doing gymnastics always land on their feet? | They spend years failing to land on their feet. Its an enormous amount of practice, and even then they aren't always perfect. | [
"Gymnasts are expected to land cleanly, with no hops or steps, and within a set landing zone on the landing mat. They must also demonstrate good technique and execution in the actual vault. Falling or stepping on landing incurs deduction, as will lack of height off the table, or distance from the table.\n",
"Foot... |
i'm an adult. why do i always dream about school? | You can think of it as a very, very mild form of Post Traumatic Stress Disorder (PTSD).
Basically, you dream of it because you went through it. If someone does go broke and lives on the streets or get very sick enough that it impacts their life, they will probably have nightmares about being back in that situation. | [
"You can learn a lot about a person from his dreams. What we dream is a reflection of who we are. It is the measure of our aspirations and goals, and of those values we hold dear and place above all else.\n",
"This group of teenagers will discover that they have more in common than they imagined, they are united ... |
Would it be inaccurate to say that in general, the common people of modern first world countries eat better than medieval European royalty? | Actually, the quality of the cuisine was generally pretty good, if you're talking about how good it would have tasted. As (and it's embarrassing to admit) a Medieval food enthusiast, I can personally vouch for how tasty the food was. It was generally very similar to the modern foods of whatever country you're looking a... | [
"European consumption of meat remained exceptional by world standards, and during the period high levels generally moved down the social scale. But the poor continued to rely mainly on eggs, dairy products, and pulses for protein. Often they did better in the less populated regions, where wild game and fish could s... |
how can someone who lost all movement from below the neck breath without aid? | In some cases they absolutely cannot, and must use a machine such as an "iron lung" or respirator.
In other cases, although their voluntary nerves aren't working, the other nerves that run automatic systems are still in good shape. | [
"It is essential that rescue breathing be continued without pause until the paralysis subsides and the victim regains the ability to breathe on their own. This is a daunting physical prospect for a single individual, but use of a bag valve mask respirator reduces fatigue to sustainable levels until help can arrive.... |
why do adolescent girls seem to be more obsessed with boy pop stars (think justin bieber, boy bands, the beatles, etc.) than adolescent boys are obsessed with female pop stars? | Boy pop stars are marketed to girls.
Girl pop stars are marketed to girls. | [
"Girls gravitate towards \"music, clothes, make-up, television talent shows and celebrities\". As young children are more exposed to and drawn to music intended for older children and teens, companies are having to rethink how they develop and market their products. Girls also demonstrate a longer loyalty to charac... |
Does Crossing-Over in Meiosis result in new genes? | It's not clear from your question whether you mean new alleles ("versions" of genes) or whole new genetic loci (sections of the chromosome), but the answer is yes in both cases!
[Crossing-over](_URL_0_) happens anywhere along the chromosome, both within and between genes. For this reason, after meiosis one gene can en... | [
"Crossing over (genetic recombination) and random segregation during meiosis can result in the production of new alleles or new combinations of alleles. Furthermore, random fertilization also contributes to variation.\n",
"If \"terminal fusion\" (restitutional meiosis of anaphase II or the fusion of its products)... |
How many mass extinctions were there, and how do we know? | Your number is correct and we know different ways.
I note that animals (and plants) go extinct all the time but in order to be a mass extinction event the extinctions have to be within a similar time frame (happen over the same span of time which isn't just instant but can cover thousands of years - such as the curr... | [
"The first of five great mass extinctions was the Ordovician-Silurian extinction. Its possible cause was the intense glaciation of Gondwana, which eventually led to a snowball earth. 60% of marine invertebrates became extinct and 25% of all families.\n",
"There have been at least five mass extinctions in the hist... |
why arent any saudi royals on the top billionaire lists? are they not filthy rich from oil? | Those guys are also not particularly transparent. Since Saudi Arabia is an absolute monarchy, the country's budget and state investment funds are also the royal family's own wallet, whereas "conventional" billionaires own far more easily detectable corporate assets. | [
"Nasser Ibrahim Al-Rashid (born 1939) () is a Saudi businessman. He is reputedly an influential advisor to the Saudi royal family and a US dollar billionaire. However he is not included in the \"Forbes\" list of the world's richest people as his personal wealth, like that of many Saudi insiders, cannot be assessed ... |
why does it matter that young people don't vote? | Broadly speaking, young people not voting shows there is a lack of engagement. This can mean they don't feel like anything will change, or can change.
This matters because for democracy to function properly (i.e. have checks and balances, a knowledgable electorate etc.) people actually have to give a damn. And what ... | [
"One reason cited for why children and the mentally disabled are not permitted to vote in elections is that they are too intellectually immature to understand voting issues. This view is echoed in concerns about the adult voting population, with observers citing concern for a decrease in 'civic virtue' and 'social ... |
I am a Roman equite from the age of Augustus examining Rome during the reign of Constantine. What has changed most noticeably? Is the new Rome even recognizable to me? | ^I'm ^not ^sure ^what ^you ^mean ^by ^"examining ^Rome". ^If ^you ^mean ^something ^like ^walking ^through ^the ^city ^of ^Rome, ^this ^would ^be ^my ^answer:
& nbsp;
Rome has changed massively between the reign of Augustus (27 BCE - 14) and that of Constantine (306-337). Most major monuments are completely new to y... | [
"Many consider Augustus to be Rome's greatest emperor; his policies certainly extended the Empire's life span and initiated the celebrated \"Pax Romana\" or \"Pax Augusta\". The Roman Senate wished subsequent emperors to \"be more fortunate than Augustus and better than Trajan\". Augustus was intelligent, decisive,... |
why does eating human flesh lead to "the shakes"? | Kuru is a real life disease caused by a prion transmitted through consumption of infectious brain matter.
It was first noted in Papua New Guinea in the 1950s and 60s and has largely remained only in that area due to endocannibalistic practices. They eat their dead.
Eating the flesh of a person who wasn't infected wit... | [
"In modern humans, necrophagy (eating of dead/decaying flesh) occurs rarely in most societies. This is likely an adaptation to the risk of disease, due to humans having lower levels of protective acids in the digestive tract, compared to species that are dedicated scavengers. Many instances have occurred in history... |
what actually are the trigometric fuctions? | EE student bored at a huge family Thanksgiving meal, I'll give this a shot.
The sine function takes an angle, traditionally labeled 'theta', as its input, and spits out the corresponding ratio between the opposite and hypotenuse sides of a triangle. Specifically, using [this image](_URL_2_) as a reference, you can say... | [
"In the mathematical study of rotational symmetry, the zonal spherical harmonics are special spherical harmonics that are invariant under the rotation through a particular fixed axis. The zonal spherical functions are a broad extension of the notion of zonal spherical harmonics to allow for a more general symmetry ... |
Why doesn't the US-Canada border follow the St. Lawrence River all the way to the Atlantic? | A very brief answer can come from looking at patterns of European colonialism. The Mississippi river, the St. Lawrence, the Columbia, the Fraser, all these are rivers that when they reach the ocean they come out in the middle of a political unit rather than as a boundary. This is largely because while rivers can repres... | [
"Development of the St. Lawrence River which serves as a border between Canada and the United States was in its early stages in 1871 when the Treaty of Washington was signed, which in part demarcated the St. Lawrence River as a boundary and offered Americans greater use of the Canadian side of the river for shippin... |
What type of weapons would have been available to medieval peasants? | Many of them would have access to spears, which would probably constitute the bulk of their weaponry. Also, depending on the time and place, many would also be equipped as archers. Many small villages had competitions for archery on a regular basis, especially in England. The spears, in particular, are easy and super-c... | [
"As far back as medieval times, if not Biblical times, there was pressure from landowners to demand heaped bushels of commodities from their peasants, while at the same time peasants were obliged to purchase commodities from stricken containers. Rules outlawing this practice were circumvented through use of heavy r... |
At what point did European settlers outnumber Native Americans in what would become the modern United States? | This is a huge, and interesting, question. I'm afraid our current data can only go so far in providing an answer. What follows is an analysis of the data, and the pitfalls of trying to definitively answer this question due to everything from notions of identity, evolving racial categories, and lack of solid sources. I ... | [
"Henry F. Dobyns estimates that immediately before European colonization of the Americas there were between 90 and 112 million people in the Americas; a larger population than Europe at the same time. \n",
"With the advancement of European colonization in the territories of the contemporary United States, the Nat... |
why does the body consume carbohydrates first and then fats when exercising? | The actual answer is a bit more complicated than that. What cells actually use for fuel is ATP, which is an energetic protein that we make using carbohydrates, fats, and other things as a fuel source.
ATP is mostly produced by mitochondria, organelles inside cells, and muscle cells have a lot of mitochondria.
At any ... | [
"Carbohydrates are the main source of energy in organisms for metabolism. They are an important source of fuel in exercise. A study conducted by the Institute of Food, Nutrition, and Human Health at Massey University investigated the effect of consuming a carbohydrate and electrolyte solution on muscle glycogen use... |
What is actually happening when I hear my timber framed house 'crack'? | It would be better described as creaking rather than cracking. When a door creaks, the hinges aren't cracking, there's just resistance that builds up until friction can no longer stop the hinge from moving. The same applies to the beams in your house as some parts of the wood heat & expand faster than others. | [
"An investigation of the scene afterwards found that seventeen joints had given way causing a hole approximately long to open up in the stand. Several witnesses in the crowd reported hearing loud cracking noises prior to the collapse and one witness, who worked as a joiner, claimed to have seen the wooden boards sp... |
why can't a country in a trade surplus be sustained in that position indefinitely? | It can.
Imagine you have a job at a convenience store where they give you a 50% discount on baseball cards. You don’t care for them much, but your friend does. He regularly buys them from you for 90% of list. You never buy anything from him.
Your friend has a trade deficit with you. The trade, though, is beneficial ... | [
"If a country's resources were not fully utilized, production and consumption could be increased at the national level without participating in international trade. The whole raison d'être of international trade would disappear, as would the possible gains. In this case, a State could even earn more by refraining f... |
This Week's Theme: Immigrants and Emigrants | **Current:** Immigrants and Emigrants
**On Deck:** Trauma
**In the Hole:** The Balkans
Remember to ask theme-related questions in [a new thread!](_URL_1_)! If your submission doesn't get automatically flaired, [send us a modmail](_URL_0_) with a link! | [
"\"The Emigrants\", the works about the Swedish emigration to North America, written by Vilhelm Moberg that have spread around the world have put a focus on many places in the municipality mentioned in the novels. Moberg himself was born on a farm just north-west of the town Emmaboda in 1898, where a monument stone... |
- why is citizen kane considered to be the pinnacle of movie making? | It's less about being the pinnacle of movie-making and more about being the _start_ of modern movie-making.
In _Citizen Kane_, director Orson Welles revolutionized how films were shot. There are a number of cinematic techniques that were introduced in _Citizen Kane_ including low angle shots, multiple dissolves, deep... | [
"In the decades since, its critical status as the greatest film ever made has grown, with numerous essays and books on it including Peter Cowie's \"The Cinema of Orson Welles\", Ronald Gottesman's \"Focus on Citizen Kane\", a collection of significant reviews and background pieces, and most notably Kael's essay, \"... |
what is the difference between federal debt and u.s. treasury securities? | The debt is issued through the use of US Treasury securities. The government sells a bond, and the money collected from the bond buyer increases the debt until the bond is paid back. | [
"Treasury securities are backed by the full faith and credit of the United States, meaning that the government has promised to raise money from any available source to repay them. Although the United States is a sovereign power and may default on its debt, its strong record of repayment has given Treasury securitie... |
why does semen lose its white color after 5 min? | Ok, so: semen contains very little actual spermatozoa and a lot of other components, one of which are alkaloids produced by prostate to - basically - neutralize the acidity in a vagina, so that the spermatozoa survive long enough to reach the egg.
The alkaline stuff oxidises when it contacts the oxygen in air, which m... | [
"Semen that has a deep yellow color or is greenish in appearance may be due to medication. Brown semen is mainly a result of infection and inflammation of the prostate gland, urethra, epididymis and seminal vesicles. Other causes of unusual semen color include sexually transmitted infections such as gonorrhea and c... |
sinuses | Sinuses are hollow cavities in the skull to lighten the bone structure. They are lined with mucous tissue, and can be subjected to allergens, causing the mucous to swell and produce mucus. This can plug up the sinus cavities and cause pressure and pain. Why your throat swells up and goes numb really has nothing to d... | [
"In human anatomy, the carotid sinus is a dilated area at the base of the internal carotid artery just superior to the bifurcation of the internal carotid and external carotid at the level of the superior border of thyroid cartilage. The carotid sinus extends from the bifurcation to the \"true\" internal carotid ar... |
if you start off completely awake and energized but then start dozing off during a boring class or a study session, what exactly is happening physiologically to cause this ? | Your brain notices that there's nothing of interest going on at the moment, and tries to shut down to conserve energy. Your studying might be important to you in a higher-function way, but at a core animal level, it's not food, sex, stimulation, or entertainment, and so you're just wasting energy and calories (and ther... | [
"Automatic behavior can also be exhibited whilst in the REM state—subjects can hold conversations, sit up and even open their eyes. Those acts are considered sub-conscious as most of the time the events cannot be recalled by the subject. It is most common when the subject has had under 10 hours sleep within a 36-ho... |
if supermarkets have a defined science/art as to where products are located, why are they all different? | Numerous factors-
1 Store size. Different stores are different sizes, and shapes depending on the area they are situated and the availble space/ planned market.. What works for one floor plan doesn't neccesarily work for another.
2 customers. Customers in different areas like different things, so different branches ... | [
"Supermarkets are designed to \"give each product section a sense of individual difference and this is evident in the design of what is called the anchor departments; fresh produce, dairy, delicatessen, meat and the bakery\". Each section has different floor coverings, style, lighting and sometimes even individual ... |
why do people with loads of money still attempt to earn more money? if you have millions in the bank isn't that more than enough? | Generally I would say that people who are millionaires tend to have a high performance drive. They desire to always perform better. This is what made them wealthy in the first place, and this is what makes them desire ever more wealth. You can always do better.
Furthermore, once you reach the level of being a milliona... | [
"Author Ric Edelman writes: \"You don't make any money in bank accounts (in real economic terms), simply because you're not supposed to.\" On the other hand, he says, bank accounts and CDs are fine for holding cash for a short amount of time.\n",
"It is not uncommon to come across individuals from whose company a... |
What is the longest "unbroken" chain of royal or dynastic succession in known history? | Japan has the oldest continuous, hereditary monarchy in the world -- and would, I believe, even qualify as oldest if we included non-hereditary or interrupted-hereditary successions. The Japanese royal family is still in the Yamato Dynasty, which took over the Japanese throne (according to legend) in about 660 BC under... | [
"This list of current longest ruling non-royal national leaders is a list of the current living longest ruling heads of nation-states or national governments, who are not royalty, and have served ten years or longer, sorted by length of tenure.\n",
"Sobhuza's official incumbency of 82 years and 254 days is the lo... |
Why is it that humans can be sustained on some leafy plants (spinach, lettuce, kale, etc) but not others (ferns, tree & and flower leaves, etc)? | It depends on what that source has to offer. Most leafy plants commonly eaten are considered "greens" like Kale, Spinach, Arugula, etc., and are eaten for the vitamin and mineral content. "Greens" are an essentially non-caloric or low calorie, nutrient dense source of minerals that would be difficult to consume through... | [
"The plants are relatively easy to grow and care for, having few insects that feed on them. Mites, though, are known to feed on the plants. The plants are also susceptible to leaf spotting, root rot and root strangulation. However the former two can be prevented by avoiding a damp soil and the latter by frequent we... |
how to barcode scanners instantly detect what an item is, despite the barcode being at any angle and often on a crinkled surface, completeley changing the look of the code from the scanner's perspective? | The lasers that read the barcode hit it from many angles and scan it very quickly. Also barcodes have something like a checksum, where it's easy to recognize if the data that was read is garbage and needs to be read again. That's why when using hand scanners, like at the grocery store, sometimes it scans a valid item v... | [
"This application supports many different types of barcodes, including those used to identify products in commerce. The Barcode Scanner can automatically search the Web to identify a product with a barcode and use, for example, price-comparison information between vendors.\n",
"By using the barcode center marker,... |
Is there a historical reason why the US military says klick instead of kilometre? | It's not official, it is military slang, and is used purely because it is easier to say. | [
"BULLET::::- That when American servicemen heard the term during the Korean War, they heard the word as 'gook\" instead of k(g)uk which means \"national\" (maybe, thus, interpreted as nationalist) \"goo-goo\" (also \"gugu\"), a term used by the U.S. military to describe Filipinos.\n",
"The slang term \"SWAG\" is ... |
why do most websites have character limits for passwords while at the same time they force you to have an upper/lowercase letter, and a number to make your password more secure. wouldn't removing the character limit and allowing much longer passwords make them more secure than 16 characters? | Convention.
There is no technical strength to doing so. Users who will use insecure passwords without the restrictions will use insecure passwords with the restrictions, and cracking these cases isn't all that much more demanding. Meanwhile, increasing password length does substantially increase security. It would be... | [
"Many policies require a minimum password length. Eight characters is typical but may not be appropriate. Longer passwords are generally more secure, but some systems impose a maximum length for compatibility with legacy systems.\n",
"The full strength associated with using the entire ASCII character set (numeral... |
Whats the difference between Centrifugal and Centripetal force? | Its often taught in PHY 101 courses that the centripetal force is "real" while the centrifugal force isn't. In a purely inertial sense, this is true, however it oversimplifies how we often times approach a lot of real problems in physics. A lot of the confusion comes from the fact that they both describe the same phe... | [
"In Newtonian mechanics, the centrifugal force is an inertial force (also called a \"fictitious\" or \"pseudo\" force) that appears to act on all objects when viewed in a rotating frame of reference. It is directed away from an axis passing through the coordinate system's origin and parallel to the axis of rotation... |
what's actually happening when someone overeats on a regular basis and their stomach "expands"? what about in reverse when their stomach gets "smaller"? | It's not just a figure of speech. Your stomach can physically expand/stretch. [Competitive eaters expand their stomachs for competition using water](_URL_0_). It really is like a balloon in a way. The size of the actual organ doesn't change, but it's elasticity and response to food can.
The opposite is not true ho... | [
"Gastroparesis (gastro- from Ancient Greek γαστήρ - gaster, \"stomach\"; and -paresis, πάρεσις - \"partial paralysis\"), also called delayed gastric emptying, is a medical disorder consisting of weak muscular contractions (peristalsis) of the stomach, resulting in food and liquid remaining in the stomach for a prol... |
rental car insurance. | I called my insurance company to make sure that my policy is the same whether I'm driving my car or a rental. It does except for what they call "loss of use." The way I understand it, if you crash the rental, insurance will cover damages to it, but the rental company can claim losses because it would have been making ... | [
"Most rental car companies offer insurance to cover damage to the rental vehicle. These policies may be unnecessary for many customers as credit card companies, such as Visa and MasterCard, now provide supplemental collision damage coverage to rental cars if the rental transaction is processed using one of their ca... |
If Alpha Centauri had a solar system like ours, how big would the outer planet's orbit appear in the sky if visible with the naked eye? | If the planetary system was completely face on and if we assume that it's an Earth like planet orbiting at 1 AU, then it would appear approximately 4x10^-4 degrees wide. That's about 0.012 arc minutes, and a quick wiki check says that the best a human eye could do is around 1 arc minute. So no way you'll see it.
Not... | [
"Viewed from near the Alpha Centauri system, the sky would appear much as it does for an observer on Earth, except that Centaurus would be missing its brightest star. The Sun would be a yellow star of an apparent magnitude of +0.5 in eastern Cassiopeia, at the antipodal point of Alpha Centauri's current right ascen... |
Can you name some important historical travelogues? | Forgive me, I am not certain what you mean by 'undercover regions'. Lady Mary Wortley Montagu's travel writings on Turkey and other countries are used as primary sources. Her relish in appealing to her audiences means her writing isn't always reliable as verbatim records of events, but is insightful for us for a rang... | [
"BULLET::::- Travel Writing: The text of most of the best known historical British travel writers, including James Boswell, William Camden, William Cobbett, Daniel Defoe, Celia Fiennes, Charles Wesley and Arthur Young. The earliest source included in the GB Historical GIS is a survey of Wales written by Giraldus Ca... |
During WW2, were there any significant acts of sabotage executed by the Axis powers on U.S. soil? | The case of Ex Parte Quirin is of note here, if only to show how inept German sabotage was for the time. A handful of covert German operatives deposited by submarine on the American eastern coast landed in uniform, to comply with the laws of war, buried their uniform, to get around the laws of war, and then started to ... | [
"During World War II PRR carried troops and matériel for the Allied war effort, and the Curve was under armed guard. The military intelligence arm of Nazi Germany, the \"Abwehr\", plotted to sabotage important industrial assets in the United States in a project code-named Operation Pastorius. In June 1942 four men ... |
[mod post] coming soon...on rules and mods. | Can we make sure the rules do more to encourage searching for answers first? Especially around big news events, the old classics of '3d printing' and 'schrodingers cat' come up constantly too. A giant red bar that flashes up when you mouse over submit like on askscience or TIL might help. | [
"The purpose of Mod DB is to list the mods, files, tutorials and information of any games that are capable of being modded with user-made content. Community involvement is strongly encouraged, and any game mod with a website is allowed to post a screenshot gallery, news, and requests for help. Scott's intentions, f... |
How accurate are the assumptions made by the blog medievalpoc concerning nonwhite peoples in medieval Europe? | So, for the record there was [this conversation last week](_URL_0_) which examines some underlying assumptions in using 'race' as any sort of measuring stick of human descriptions before our epoch.
'Non-white', the same as 'black', or 'asian', or any other modern race definition are just that, modern which is what /u/... | [
"Digital Medievalist sees it as its mission to provide a framework to enable members of its community to share information. These activities include an electronic mailing list, the participation in and organisation of conference sessions or other events, and a website containing an open-access academic journal of r... |
When did Americans start using French words and phrases, and why are they so prevalent? | Although English is a Germanic language, approximately 30% of English vocabulary comes from French in one form or another. This is largely caused by an event called the Norman Conquest, in which a group of people called Normans, who inhabited Northern France and had a degree of Scandinavian ancestry, invaded and conque... | [
"As American soldiers and officials traveled through the area for the first time following the War of 1812, they initially used the French spelling. But when large numbers of lead miners streamed into the country south of the river in the 1820s, the U.S. government began to refer to it differently in debates and le... |
Could we use magnetism as opposed to rocketry to launch objects/people/spaceships into orbit? | People talk about doing something like this:
The mass driver, which is similar to some designs for high-speed trains.
_URL_0_
In most cases it's not practical to launch from Earth's surface to orbit with one of these, since you have to launch at high speed through the atmosphere, and your capsule would ... | [
"The science of electromagnetic propulsion does not have origins with any one individual and has application in many different fields. The thought of using magnets for propulsion continues to this day and has been dreamed of since at least 1897 when John Munro published his fictional story \"A Trip to Venus\". Curr... |
why are there so many contradictory ideas about what humans should be eating, but other animals are very straightforward in knowing what to eat? | We have the technology to make whatever we want and the resources to get whatever we want. We have a lot more choices than an animal does. It also helps that we're omnivores and able to make any type of food digestible and tasty, while many other animals are stuck being unable to digest one thing or the other.
Animals... | [
"Ultimately, \"Eating Animals\" discusses the ethics of food. It suggests that our food choices directly reflect the ethical values we stand for. When people eat meat, Foer claims, they are implying that satisfying their desire for meat is more important than letting animals live well, or even live at all. This can... |
In the 1920s, what did people feel nostalgia towards? | This is not to prevent anyone from writing you a full, new answer, but you may be interested in these two answers of mine:
[Why are people today fascinated with the Victorian era?](_URL_0_)
[Dang kids! Or: Why does each generation have such an exaggerated view of fashion in previous ones?](_URL_1_) | [
"In the eighteenth century, scientists were looking for a locus of nostalgia, a nostalgic bone. By the 1850s nostalgia was losing its status as a particular disease and coming to be seen rather as a symptom or stage of a pathological process. It was considered as a form of melancholia and a predisposing condition a... |
The USA had a large percentage of German immigrants in the early 20th century. What was life like for them during WWI and WWII? Did many serve the Allies or did any go back to the “Fatherland”? Also why did the US sell to the British and not the Germans before they entered both wars? | One of the first things you need to think about is why the Germans came over to the US. The vast majority of immigrants came after the failed Democratic revolutions in the 1890s, so they wanted to live in Republican state. That being said while these Germans hated the Kaiser they didn't want war between the US and Germ... | [
"Before 1900, the main factors in German-American relations were very large movements of immigrants from Germany to American states (especially Pennsylvania, the Midwestern United States, and central Texas) throughout the 18th and 19th centuries.\n",
"But immigrants from Germany, as well as German Americans from ... |
Does brushing your tongue harm your taste buds? | Dentist here.
To answer your question about tongue brushing and potential damage to our taste receptors. Yes and No.
Let's start with how it would be a Yes, and work in to the final answer of No:
If you are using a hard bristled toothbrush, highly corrosive toothpaste (usually whitening toothpaste or something with ... | [
"Tongue cleaning can cause discomfort. Improper use of a tongue cleaner may induce the gag reflex and/or vomiting. Overuse of a tongue cleaner may also cause damage to the taste buds. Some people have inappropriately used the tongue cleaner to scrape or brush the lingual tonsils (tongue tonsils).\n",
"The tongue ... |
if redbull lost a lawsuit over their "gives you wings" slogan, how do the current commercials still include the slogan without a small disclaimer included? | Actually, that law suit (for $13.5 million) was not because of the tagline "give you wings" (which is clearly understood as humor).
The law suit was over the fact that Red Bull oversold the drink's ability to improve concentration and energy, specifically, it did not provide any scientific evidence to support their cl... | [
"In 1999, animated advertisements were part of the early GEICO Direct ads as well as the \"Dumb Things\" campaign. The 15-second long commercials, animated by Bill Plympton, featured a curious little man walking up to an object and eventually getting hurt due to his curiosity about the object. One of the commercial... |
What gods were foreign and then adopted by the Greeks and Romans through trade/war/etc? | A few of the most famous examples of Roman religious syncretism are the cults of Isis, Mithras, and Sulis.
Isis was an Egyptian goddess of magic and mother of Horus, God of the Pharaoh. She was an incredibly important figure in the Egyptian pantheon so it's no small wonder that her cult thrived under the rule of the P... | [
"In the subsequent Greco-Roman period, there is evidence that the worship of non-indigenous deities was brought to the region by merchants and visitors. These included Bel, a god popular in the Syrian city of Palmyra, the Mesopotamian deities Nabu and Shamash, the Greek deities Poseidon and Artemis and the west Ara... |
If the salt water in the ocean accumulated over time was there ever a point where it was all freshwater? | Perhaps briefly (on a geological timescale), when the atmosphere cooled enough for the first rains to fall, the resultant bodies of water may have been pure enough to be considered freshwater with less than 500ppm of dissolved salts. There were almost surely multiple phases of the early Earth's surface water inventory... | [
"Scientific theories behind the origins of sea salt started with Sir Edmond Halley in 1715, who proposed that salt and other minerals were carried into the sea by rivers after rainfall washed it out of the ground. Upon reaching the ocean, these salts concentrated as more salt arrived over time (see Hydrologic cycle... |
why does adding salt to desserts make them seemingly sweeter? | Salt changes the electrochemical reactions that happen in the chemoreceptors on your tongue (taste buds). The effect is different for different types of receptors; bitter receptors are inhibited, while sweet receptors have their sensitivity enhanced. Sweet becomes sweeter and bitter becomes less bitter (but only up to ... | [
"Desserts can contain many spices and extracts to add a variety of flavors. Salt and acids are added to desserts to balance sweet flavors and create a contrast in flavors. Some desserts are coffee-flavored, for example an iced coffee soufflé or coffee biscuits. Alcohol can also be used as an ingredient, to make alc... |
why did a law need to be passed telling federal employees that they couldn't participate in insider trading? | This is how I understand it. Can someone please fill in the details or correct me on this?
Part of the reason is because, technically, a lot of what they were doing wasn't "insider" trading. Typically, insider trading happens (e.g.) when you work for a company or are someway involved in a company and you happen to k... | [
"U.S. insider trading prohibitions are based on English and American common law prohibitions against fraud. In 1909, well before the Securities Exchange Act was passed, the United States Supreme Court ruled that a corporate director who bought that company's stock when he knew the stock's price was about to increas... |
the future of computer storage: storage capacity vs compression abilities | So far, capacity has kept increasing rapidly. You used to buy the biggest drive you could afford, knowing that it was going to be filled up all too soon anyway, but that you'd be able to get a bigger one in a few years.
These days, the capacity of a hard drive tends to be much larger than anyone needs, especially with... | [
"It is estimated that the total amount of data that is stored on the world's storage devices could be further compressed with existing compression algorithms by a remaining average factor of 4.5:1. It is estimated that the combined technological capacity of the world to store information provides 1,300 exabytes of ... |
Can a satellite maintain an orbit forever under ideal conditions? | Purely from Newtonian gravity - i.e., the gravity you learn about in high school - there's no decay under ideal conditions. But we've known that picture of gravity is wrong for nearly a century. The more modern theory, Einstein's theory of general relativity, allows for gravitational radiation, and any orbit will radia... | [
"Each satellite has a design life of twelve years, with an orbital maneuver life of 15 years, which means that each satellite has been designed and fueled to maintain its assigned orbital position (within 0.1 degrees) for 15 years. After that point, the satellite must be decommissioned. The AfriStar satellite has d... |
Do satellites travel with the rotation of the earth or against and if they go both ways would two identical satellites going opposite directions at the same altitude have to travel at different speeds to maintain orbit? | Most satellites are in prograde orbits, meaning that they orbit in the same direction that the earth rotates. This is because retrograde orbits, which orbit opposite the direction of the earth's rotation, require more fuel to launch.
Think of it like this. If you're in a car going 5 mph and you want to get a projectil... | [
"Because a satellite in an eccentric orbit moves faster near perigee and slower near apogee, it is possible for a satellite to track eastward during part of its orbit and westward during another part. This phenomenon allows for ground tracks which cross over themselves, as in the geosynchronous and Molniya orbits d... |
Scientists: What is the coolest thing you've learned in your field? | I can make a big list actually, of moments I just had to stop and take a moment to digest that. Some of them:
1. The first time I saw the first division of a C. elegans embryo under a microscope. Its quite big so you can see all the aspects of cell division happening with your own eyes and its the most magical thing I... | [
"Described by Discovery as a \"commercial free hour of \"MythBusters\" mashups, hosted by Kari Byron\", the show features about ten minutes of new material—experiments and quizzes presented by Kari, as well as TV celebrity and scientist appearances, pitching the idea that \"science is cool\"—interwoven in fifty min... |
why is vibrato singing considered good? | Long notes can sound boring. Vibrato is intended to add some colour and variety during the course of the note.
Vibrato is a skill... but an equally important skill is knowing when and how to use it. It probably shouldn't be used in every note, or for the whole length of the note. The speed and the intensity of the vib... | [
"Vibrato is often perceived to create a more emotional sound, and it is employed heavily in music of the Romantic era. The acoustic effect of vibrato has largely to do with adding interest and warmth to the sound, in the form of a shimmer created by the variations in projection of strongest sound. A well-made violi... |
Was every desert once a body of water? | It's hard to say definitively whether or not every desert was once under a body of water, but desertification of once arable land is possible with poor land management, such as what happened with Africa after the Romans cut down all the trees. Sand is kind of always there, it's the vegetation and bio-mass that gets car... | [
"Scientists agree that the existence of a desert in the place where the Sahara desert is now located is due to a natural climate cycle; this cycle often causes a lack of water in the area from time to time. There is a suggestion that the last time that the Sahara was converted from savanna to desert it was partiall... |
What happens to gut flora if a person is dying of starvation or dehydration? | Depending on where in the gut you're looking at, it may change. During starvation, your stomach acid may become more concentrated, and stronger - thus a small amount of bacteria in the proximal duodenum (small bowel coming right off the stomach) may be killed. This would be very minimal, since there are glands in the p... | [
"The underlying starvation, malnourishment, and usually dehydration, associated with emaciation, affect and are harmful to organ systems throughout the body. The emaciated individual experiences disturbances of the blood, circulatory, and urinary systems; these include hyponatremia and/or hypokalemia (low sodium an... |
how were length/liquid measurements kept the same everywhere? | The short answer was, they didn't. Standards varied heavily from region to region. Keep in mind, back then, travel/trade was *a lot* harder, so the effects were much less noticeable.
In some cases, once things were more developed, they would have a standard- then they'd copy that standard and ship them around the worl... | [
"Before the 1843 changeover, different units were used to measure length. One pic (dzera à torky) was equal either to 0.64 m or 0.623 m), while a different pic (dzera à rabry) was equal to 0.48 m or 0.467 m). Some other units are given below:\n",
"The history of the measurement of length dates back to the early c... |
Why can't you tame a Zebra? | "Taming" isn't all-or-nothing. There's a range of behaviors that includes whether the animal attacks humans, runs away from humans, tolerates being touched, tolerates various medical examinations and procedures, responds to commands, actively seeks human company, and so on.
The zebras at the San Francisco Zoo will do ... | [
"Zebras have four gaits: walk, trot, canter and gallop. They are generally slower than horses, but their great stamina helps them outrun predators. When chased, a zebra will zig-zag from side to side, making it more difficult for the predator to attack. When cornered, the zebra will rear up and kick or bite its att... |
Is the earths ozone layer capable of changing position? | Well, the ozone layer is ubiquitous through the stratosphere. In fact, the predominant sources of ozone are in the tropics, and it's overturning circulations like the Brewer-Dobson that transport ozone to the poles through the year - at least until the polar vortex develops, which cuts off that transport.
You don't re... | [
"The ozone hole is usually measured by reduction in the total \"column ozone\" above a point on the Earth's surface. This is normally expressed in Dobson units; abbreviated as \"DU\". The most prominent decrease in ozone has been in the lower stratosphere. Marked decreases in column ozone in the Antarctic spring an... |
how does paypal make money/stay in business? | If you are a merchant selling something through them they take a 2.9% + $0.30 cut of your profit. | [
"PayPal's services allow people to make financial transactions online by granting the ability to transfer funds electronically between individuals and businesses. Through PayPal, users can send or receive payments for online auctions on websites like eBay, purchase or sell goods and services, or donate money or rec... |
Three questions about the Napoleonic army. | During a campaign, an officer was generally allowed a small Wagon to carry personal effects and anything necessary for his work in the field. This would range from a tent and necessary notes to liquor and personal reading. Naturally the higher the rank the more you'd be able to have bit the more you'll also need for yo... | [
"Napoleon led a new army to the Battle of the Nations at Leipzig in 1813, in the defence of France in 1814 and in the Waterloo Campaign in 1815, but the Napoleonic French army would never regain the heights of the Grande Armée of June 1812.\n",
"Under Napoleon I, the French Army conquered most of Europe during th... |
What people does the Assyrians descend from? | This is a somewhat controversial topic within the Syriac christian community. Basically there are two main schools of thought: those who identify as Assyrians and descendants from the ancient Assyrians and those who identify as Arameans and their descendants. I will let someone with the 'Assyrian' origin point of view ... | [
"In Church tradition, the Assyrians are descended from Abraham's grandson (Dedan son of Jokshan), progenitor of the ancient Assyrians. Along with the Arameans, Phoenicians, Armenians, Greeks and Nabateans, they were among the first people to convert to Christianity and spread Eastern Christianity to the Far East.\n... |
you know how you can tense up certain muscles in your foot or leg and pretty immediately give yourself a cramp? why do your muscles have those 'pressure points' or non-random cramp areas, and why is it so easy to bring about a cramp in them? | I tried to read up on this, and also asked my doctor about it, and it seems to not be totally known, in part because there can be a lot of different reasons depending on the person and circumstances.
I think these are usually technically muscle spasms rather than cramps, although they're similar.
Some possible causes... | [
"A cramp is a sudden, involuntary muscle contraction or over-shortening; while generally temporary and non-damaging, they can cause significant pain, and a paralysis-like immobility of the affected muscle. Onset is usually sudden, and it resolves on its own over a period of several seconds, minutes or hours. Cramps... |
how can the hubble space telescope keep its lens pointed in the same spot to take long exposure shots when it's orbiting the earth every 97 minutes? | Hubble uses six gyroscopes to know exactly where it's pointing. These are devices that act a bit like a compass, and always point in the same direction even when the telescope is orbiting.
Next it has four reaction wheels which actually move the telescope. These just use Newton's 3rd law of motion; if the wheel spins ... | [
"The Hubble Space Telescope has three fine guidance sensors (FGSs). Two are used to point and lock the telescope onto the target, and the third can be used for position measurements - also known as astrometry. Because the FGSs are so accurate, they can be used to measure stellar distances and also to investigate bi... |
what do fireworks event companies do the rest of the year? how do they stay profitable? | Sporting events mostly. A lot of minor league baseball teams have displays at the end of weekend games. Same with other sports as well. | [
"Fireworks Entertainment was an independent studio founded by Jay Firestone in 1996 to produce, distribute and finance television shows and feature films. Fireworks was acquired by Canwest Global in May 1998, and was later sold to ContentFilm (production company of The Cooler), a British company, in April 2005. Ove... |
Why didn't land animals evolve to dinosaur size again after their extinction? | From our [FAQ](_URL_5_) (which I wrote, hence the copypasta):
There have been much larger terrestrial mammals in the past. [*Paraceratherium*](_URL_6_) is an example. There are also mammals alive today that are as large or larger than the largest dinosaurs (blue whales!). However, the fact remains that some dinosaurs ... | [
"BULLET::::- Archibald argued that the withdrawal of shallow seas from Earth's continents during the Late Cretaceous reduced the size of and fragmented the coastal plain habitats preferred by large dinosaur species and that this fragmentation may have driven some taxa extinct.\n",
"After the Cretaceous–Paleogene ... |
what is computer science? | So, this rundown is my own, and the idea here is to have a pseudo-historical list running in descending order of abstraction. Basically, I'll start with the most abstract and general ideas of the field, and work down towards nitty gritty practical bits that emerged.
But anyway, the main idea of computer science is to ... | [
"Computer science is known by its near synonyms, like Information Technology (IT) and Computing. At the beginning, only a few students can get computer science education, but as time passes, it’s popular in ordinary people. In UK, in 1981, only A level students can get it, but in 2014, even common pupils can study ... |
What defines the maximum and minimum wavelength of electromagnetic radiation? | There is no maximum or minimum wavelength, any wavelength can be transformed into another one with the right choice of reference frame. A possible exception to this is if quantum gravity breaks Lorentz symmetry, and then there will be some minimum Planck-scale wavelength. | [
"The electromagnetic spectrum extends from below frequencies used for modern radio to gamma radiation at the short-wavelength end, covering wavelengths from thousands of kilometers down to a fraction of the size of an atom. That would be wavelengths from 10 to 10 kilometers. The long wavelength limit is the size of... |
when i wake up at 3 am to pee, why does keeping my eyes closed for my trip to the bathroom seem to help me get back to sleep faster? | Your brain has this thing called a circadian rhythm. What it's designed to do is make you sleepy at night time and wakeful during the day. Unfortunately, your body doesn't have a clock inside of it so it has to rely on cues outside of you to know when it's night and when it's day. One of the cues your body uses is ligh... | [
"\"Urinating in bed is frequently predisposed by deep sleep: when urine begins to flow, its inner nature and hidden will (resembling the will to breathe) drives urine out before the child awakes. When children become stronger and more robust, their sleep is lighter and they stop urinating.\"\n",
"Mowrer detailed ... |
When a hot surface (a grill) is radiating hot air, why is there distortion in the air above it? | The angle at which air refracts light changes based on density. There is a temperature and density gradient between the hot grill and relatively cool surrounding air. | [
"Convection causes the temperature of the air to vary, and the variation between the hot air at the surface of the road and the denser cool air above it creates a gradient in the refractive index of the air. This produces a blurred shimmering effect, which affects the ability to resolve objects, the effect being in... |
Is there any evidence that essential oils actually do anything other than smell good? | Essential oil simple means that is possess a smell similar to the plant it is derived from. It isn't based on anything medical related. Now that doesn't mean that they arn't good for you, it just means that it is a large category that isn't related to anything medical. Its sort of like asking if the category food is go... | [
"Essential oils are volatile and liquid aroma compounds from natural sources, usually plants. They are not oils in a strict sense, but often share with oils a poor solubility in water. Essential oils often have an odor and are therefore used in food flavoring and perfumery. They are usually prepared by fragrance ex... |
how do they move sculptures that are to big for trucks? | > Edit: ah dicks, forgot ELI5
Ha. It's ok. It's still evident this is a legit ELI5 question.
I really wish there were a better answer, but they pretty much just [close down all the roads](_URL_0_). It's super inconvenient (which is why they try to do it late at night).
LA has something of a habit of frequently inc... | [
"The articulated haulers relatively small size also make them able to drive on public roads between different worksites at a large construction project—something that is impossible for the largest haul trucks, which might even have to be disassembled to be moved between different locations. For transportation betwe... |
Does "alcoholism" or "alcoholic" have a scientific definition, or is it a more subjective term? | The DSM-IV-TR has definitions for alcohol abuse and alcohol dependence - [link](_URL_0_).
It's important to note that (a) The DSM V is due very shortly and (b) There are many researchers who feel that the DSM does not use the best model.
In regards to your question, it's worth noting that the criteria are a combinat... | [
"The term \"alcoholism\" is commonly used amongst laypeople, but the word is poorly defined. The WHO calls \"alcoholism\" \"a term of long-standing use and variable meaning\", and use of the term was disfavored by a 1979 WHO expert committee. \"The Big Book\" (from Alcoholics Anonymous) states that once a person is... |
how can an aircrafts engine work at such high altitudes where humans struggle to breathe due to lack of oxygen? | The aircraft require less power at high altitude because of less air resistance but very few aircraft can operate at very high levels due to the lack of air. | [
"The human body can adapt to high altitude through both immediate and long-term acclimatization. At high altitude, in the short term, the lack of oxygen is sensed by the carotid bodies, which causes an increase in the breathing depth and rate (hyperpnea). However, hyperpnea also causes the adverse effect of respira... |
What are the heat related consequences of urination? | When urine leaves your body it is body temperature. Your body either heats, or is heated, by the cold or hot food and liquids you eat. Urinating itself does not change your body temperature as you are evacuating this temperature stabilized liquid. | [
"The temperature at which the urine is examined is a very important factor to consider in the process of uroscopy. When a patient urinates, the urine will be warm, so it is necessary for it to stay warm for proper evaluation. The external temperature should be the same as the internal temperature. When the temperat... |
why does the western world (say usa and western europe) get involved in armed local conflicts all over the world even if it doesn't have to? | Several reasons.
1) We have interconnected economies. So having trade access to resources means that some conflict that you would not think would affect a country really do affect them.
2) We now have invented weapons that are capable of destroying civilization as we know it with a push of a button. Limiting who ge... | [
"There is significant debate over whether the lack of any major European general wars since 1945, is due to cooperation and integration of liberal-democratic European states themselves (as in the European Union or Franco-German cooperation), an enforced peace due to intervention of the Soviet Union and the United S... |
What portion of the world's current gold supply was part of Atahualpa's ransom? | Let's assume that Hernando Pizarro was telling the truth about the size of the ransom and that all the promised ransom was received. Here is the description from Hernando Pizarro
> for that he could give them ten thousand plates, and that he could fill the room in which he was up to a white line, which was the he... | [
"In 1532, Francisco Pizarro was paid a ransom amounting to a roomful of gold by the Inca Empire before having their leader Atahualpa, his victim, executed in a ridiculous trial. The ransom payment received by Pizarro is recognized as the largest ever paid to a single individual, probably over $2 billion in today's ... |
Why was the practice of presenting men, who refused to enlist in the army, a white feather supported by early feminist organizations? | The so-called 'Order of the White Feather' was created in Britain in 1914 by a former admiral, and essentially involved handing out 'white feathers' to anyone, specifically men, not seen as supporting the war effort, ie not enlisting. Some British women's organizations handed out feathers, an act that symbolizes 'cowar... | [
"Despite their obvious distinctions from men, women were eager to volunteer. Many of the servicewomen came from restricted backgrounds; therefore they found the army liberating. Other reasons women volunteered included escaping unhappy homes or marriages, or to have a more stimulating job. The overwhelming reason f... |
In the Byzantine Empire, what type of names did people have? | That depends on the time period and location. Up until around the sixth century, you can see a lot of emperors having Latinate names, like Flavius Sabbatius Iustinianus (not that I'm biased!), Constantinus, or Iulianus. Later, more Hellenic names appear, like Basileios the Bulgar-Slayer or Alexios Komnenos. It's wor... | [
"Many peoples neighboring on the Byzantine Empire used names expressing concepts like \"The Great City\", \"City of the Emperors\", \"Capital of the Romans\" or similar. During the 10th to 12th century Constantinople was one of the largest two cities in the world, the other being Baghdad.\n",
"Of Byzantine origin... |
To what extent did the Soviet-Polish war cause Poland to be successfully invaded in 1939? | The Polish army was strong for a country of its economical development - it was well trained and equipped with modern arms. However, they were unable to stand up to the full power of a grand power such as Germany, and even less the power of two grand powers (Germany and the Soviet Union).
The Soviet-Polish war and the... | [
"The Polish–Soviet War (February 1919 – March 1921) was an armed conflict between Soviet Russia and Soviet Ukraine on the one hand and the Second Polish Republic and the short-lived Ukrainian People's Republic on the other. The war was the result of conflicting expansionist ambitions. Poland, whose statehood had ju... |
why is perpetual energy from gravity impossible? | Gravity pulls things down. You can exploit this for energy, but only once.
Once the object has exhausted its "gravitational potential" (i.e. hit the ground) you can't extract any more without first picking it up again.
We do extract energy from falling water in hydroelectric dams, but again the water can only pass t... | [
"Gravity also acts at a distance, without an apparent energy source, but to get energy out of a gravitational field (for instance, by dropping a heavy object, producing kinetic energy as it falls) one has to put energy in (for instance, by lifting the object up), and some energy is always dissipated in the process.... |
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