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i know this has been asked before, but i still can't wrap my head around it. minimum wage. | It's a complex issue and hard to study by it's nature, so nobody really knows if increasing the minimum wage is beneficial or not. Here's a ELI5 explanaition of both sides:
**Against**
Raising the minimum wage raises makes the profit margin for businesses with lots of minimum wage employees smaller since it raises their costs. So they can either choose to hire fewer people (which would hurt their ability to run their business) or eat the loss and hope it doesn't drive them out of business.
A minimum wage increase kills jobs in two ways. Firstly, but discouraging hiring by making it cost more. Secondly, by increasing the cost of doing business, which will cause businesses to close down, which means the people who worked there are now without a job.
**For**
The purpose of the minimum wage isn't meant to increase jobs, it's meant to provide a wage that people can live off of. I've been to a factory in China where they had dorms on site for the workers to live in. A minimum wage prevents that type of situation.
In addition, a minimum wage hike only effects some businesses. I work at a bank with over 3000 employees, and I would be surprised if a single one makes minumum wage.
That brings us to the argument that minimum wage actually increases jobs. My bank is more profitable when more people have more money, because those people will put more money in their accounts and get more loans.
This is the case for just about every business, and the core of a lot of liberal economic policies. Poor people are much more likely to spend any money you give them than rich people are, so when you give poor people money it goes right back to businesses. McDonalds may have to pay their employees more, but they also get more money from customers because suddenly people have more money. | [
"A minimum wage is the lowest remuneration that employers can legally pay their workers—the price floor below which workers may not sell their labor. Most countries had introduced minimum wage legislation by the end of the 20th century. \n",
"The minimum wage is the minimum wage required for human life and the ba... |
up arrow notation like in graham's number. | When you multiply two numbers (m x n), you're really just adding m to itself n times. For example:
* 4 x 3 = 4 + 4 + 4 = 12.
The Knuth up-arrow notation was developed to make very large numbers easy to deal with. To get to Graham's number (3 ↑ ↑ ↑ ↑3), let's first look at what an exponent is. m^n is (just like multiplication) m times it self n times.
* 3^3 = 3 x 3 x 3 = 27.
This is what the m ↑n represents:
* 5^3 = 5 ↑3 = 125
So now, there is a symbol that represents doing the 'lesser order' operation a number of times. Let's go one step further. Just as m ↑n is m^n, m ↑ ↑n taking m to the power of it self n times. This is known as tetration. Put simpler:
* 2 ↑ ↑3 = 2^(2^2) = 2^4 = 16 = 2 ↑2 ↑2
* 3 ↑ ↑3 = 3^(3^3) = 3^27 = 7625597484987 = 3 ↑3 ↑3
Now is when this gets a bit more tricky. So we know that each arrow represents a iteration of the previous arrow operation. The next step in the arrow notation is m ↑ ↑ ↑n. This is m tetrated to itself n times.
* 3 ↑ ↑ ↑3 = 3 ↑ ↑3 ↑ ↑3 = 3 ↑ ↑ (762559748498) = 3^3^3^3... 762559748498 times= a very big number we'll call VBN.
Graham's number is defined as 3↑↑↑↑3*. This one is even more tricky than the last to explain without getting bogged down in notation. I'll do my best though:
* 3↑↑↑↑3 = 3↑↑↑3↑↑↑3 = 3↑↑↑VBN = 3↑↑3↑↑3 ... VBN times.
In this example, what we'd do is calculate 3↑↑3 = n, then do 3↑↑n = m, then 3↑↑m = k until we've done that VBN times.
Sorry if this doesn't actually explain what Graham's number is, but you hopefully now appreciate just how big it is!
*EDIT: This is incorrect, see Quaytsar's comment below for the definition.
| [
"In mathematics, Knuth's up-arrow notation is a method of notation for very large integers, introduced by Donald Knuth in 1976. It is closely related to the Ackermann function and especially to the hyperoperation sequence. The idea is based on the fact that multiplication can be viewed as iterated addition and expo... |
How did the British manage to mindbogglingly administer all the 500+ Princely States in India? What laws applied in these territories? | I will try to answer each of your question.
#Question 1
* Most princely 'states' were states only in name. A city or a few clusture of villages was often what constituted a 'princely state' in many cases. So the 500 number is not actually as daunting as it seems
* The British had a system called 'subsidary alliance system'. Under this system, A ruler handed over his foreign policy over to British and gave his consent to the permanent deployement of British troops inside his kingdom. In return, the princely state wont be annexed and the ruler would recieve a regular pension to maintain his lifestyle
* Most rulers of these so called princely states were sheiveled up shadow of their past ancestors. They did not have the military might to even stop a cattle robbery, much less challenge british power
* The Britiish had also enacted a policy under which rulers who did not have their own kids could not appoint adopted kids as heir. If a ruler did not have his own flesh and blood to inherit his kingdom, then the british would swoop in on his death and appoint a puppet
[To be continued] | [
"By the beginning of the 20th century, relations between the British and the four largest states – Hyderabad, Mysore, Jammu and Kashmir, and Baroda – were directly under the control of the Governor-General of India, in the person of a British Resident. Two agencies, for Rajputana and Central India, oversaw twenty a... |
Do black holes accelerate matter to light speed? | No. Massive objects always move slower than light. Also, talking about relative speed on objects that aren't in the same place doesn't generally make sense in general relativity. Usually it's not too bad, but black holes are kind of extreme. But you can still distinguish slower than light, light speed, and faster than light, and massive objects always move slower than light. | [
"Some of the best evidence for the presence of black holes is provided by the Doppler effect whereby light from nearby orbiting matter is red-shifted when receding and blue-shifted when advancing. For matter very close to a black hole the orbital speed must be comparable with the speed of light, so receding matter ... |
why are car colors so dull? | Neutral colors are going to appeal to the widest audience. Bright colors can be found but they're the exception to the rule - most people tend to gravitate toward something more subdued. | [
"The most popular car colours today are greyscale colours, with over 70% of cars produced globally being white, black, grey or silver. Red, blue and brown/beige cars range between 6% and 9% each, while all other colours amount to less than 5%.\n",
"The use of these colours in retro-reflective material is controll... |
How did painters react to the invention of photography? Did they oppose it or did they embrace it as an emerging art? | Follow-up question: Did the increasing quality and affordability of photography in the late 1800s help popularize Impressionism, since it purposefully didn't attempt to realistically recreate landscapes? | [
"The invention of photography had a major impact on painting. In the decades after the first photograph was produced in 1829, photographic processes improved and became more widely practiced, depriving painting of much of its historic purpose to provide an accurate record of the observable world. A series of art mo... |
why are asians discriminated against in college admissions, and how extensively are they put to a disadvantage? also, why are people okay with putting asians at a disadvantage, but not african-americans or hispanics? | Asians make up around 6% of the US population but account for 20 - 40% of college students in America. As a result Asians are vastly over represented in Universities and thus don't need protection like other minorities which tend to be under represented. Many people look at how well Asians are doing in getting into universities and figure since they are over represented it is merely "correcting" the situation to cap how many get in.
| [
"Aside from corporate underrepresentation, there is also a bias against students applying to colleges; there seems to be a racial quota established in several schools that limits its enrollment of Asian-American applicants. This existing bias is explained by professor of Public Policy at University of California Ri... |
how does something like the james webb space telescope cost $8 billion? | Who made it? A huge team of NASA engineers working for years and years to develop technology never seen before. These are real smart dudes who don't work for chump change. | [
"The James Webb Space Telescope is a planned international 21st century space observatory. It is intended to be a premier observatory of the 2020s, combining the largest mirror yet on a near-infrared space telescope with a suite of technologically advanced instruments from around the world. JWST is expected to cost... |
How long is a nuclear ground zero uninhabitable? | Standard thermonuclear weapons have a fallout that will typically degrade to habitable levels within 6-18 months.
A ground detonation would produce a more severely affected local area of irradiation whereas an air burst would ultimately cover such a broad area that it would be diffused and relatively harmless.
After an atomic explosion the fallout is entirely airborne particulate and is more easily blown away or swiftly incorporated into the water cycle and dispersed compared to a nuclear meltdown.
Of great concern, should one ever be built or detonated, is a Cobalt Bomb. This is a kind of "salted" nuclear weapon where a large amount of cobalt is added to the device and the reaction turns it into the highly radioactive cobalt-60. This would produce levels of radiation that are overall less than a standard weapon but render an area completely uninhabitable for up to 5-10 years.
A Cobalt bomb could produce the kind of post apocalyptic wasteland we've come to expect from popular culture. | [
"Ground zero describes the point on the Earth's surface closest to a nuclear detonation. In the case of an explosion above the ground, ground zero refers to the point on the ground directly below the nuclear detonation. \n",
"In terms of nuclear explosions and other large bombs, the term \"ground zero\" (also kno... |
How did people do their taxes before computers were invented? | No scholarly links or background here but a first hand account of someone that was around in the bad old days of tax before computerized submission.
You got a form, you filled it in. There were instruction booklets of various degrees of helpfulness & help lines you could call. If paperwork wasn't your thing, well this is the reason H & R Block was created.
| [
"By the end of the Second World War, the IRS was handling sixty million tax returns each year, using a combination of mechanical desk calculators, accounting machines, and pencil and paper forms. In 1948 punch card equipment was used. The first trial of a computer system for income tax processing was in 1955, when ... |
if evolution promotes survival, why do living things die naturally | Evolution promotes survival of the species, not of individual organisms.
If anything, a species being immortal would be an evolutionary disadvantage as you are guaranteed to run into overpopulation and the subsequent exhaustion of resources. | [
"Contemporary evolutionary theory sees death as an important part of the process of natural selection. It is considered that organisms less adapted to their environment are more likely to die having produced fewer offspring, thereby reducing their contribution to the gene pool. Their genes are thus eventually bred ... |
how does my dog have a habitual schedule daily but doesn't understand time? everyday he knows when his dinner should be made by messing with his bowl or making noises around 5 o'clock. but can't tell the difference between 3 days or 3 hours? | Just as animals in the wild having sleeping, eating, and mating schedules, so does your dog. He knows about the time he supposed to be fed. Or maybe he just tells you when he is hungry. My dog will whine if I forget to feed him in the mornings, which is rare, but he still knows he wants to be fed. He has a concept of time, just not as sophisticated as we revolve our lives around time. | [
"The Dog Team had an unusual system of serving. Upon arriving at the restaurant, the menu was presented on a board just inside the entrance way. Customers gave their names and orders at that time, and went inside the building to wait. Waiting times of an hour or more were not uncommon during busy times.\n",
"87. ... |
differnt blood types and their impact. | Human blood falls into the catgories of A, B, AB, and O depending on the presence of certain markers on the red blood cells known as antigens. These antigens allow the body to recognize and distinguish its own cells form foreign red blood cells as part of our immune system. This occurs as each antibody is grouped with an opposite antibody contained in the plasma of the blood (ie blood type A would have B antibodies, B with A antibodies, AB with neither antibody, and O with both antibodies). They work in a lock and key fashion in which if an antibody is able to lock with an equal antigen, then an immune response is triggered (as it implies the presence of foreign red blood cells). This has major implications as to who can safely transfer blood to each other with A being able to recieve blood from A and O, B from B and O, O from O, and AB from A and B. Now getting to your questions, i myself dont know specifically if blood type has an impact on health, though i can see a lot of articles pop up on google. | [
"substances on the surface of red blood cells, and an individual's blood type is one of many possible combinations of blood-group antigens. Across the 36 blood group systems, 308 different blood-group antigens have been found. Almost always, an individual has the same blood group for life, but very rarely an indivi... |
What was the extent of the Scots-Irish influence on the Blues? | I'm not certain that this is what you're looking for, but if you're referring to the type of blues that originated in the Mississippi River area (Delta, Chicago, etc.), they were at least minimally influenced by what's called "old time" music. Old time music is more or less what people today think of when they hear "bluegrass", even though old time is sometimes slower and more reflective of "tough" times. African-Americans in the South, post-1865 at least, combined their natural African instruments and styles/dances with those of the white, European-descended old time players (guitars, fiddles, and banjos...which probably originated in Africa) and began to create what we know today as "blues" music. True blues music flourished in places where African-Americans were struggling the most. Starting in the rural Mississippi River delta area of Mississippi, Arkansas, Louisiana, and extreme southwest Tennessee, and eventually slowly migrating to Northern cities with African-Americans, most notably Chicago. | [
"The Blues went in yet another direction, when it started to mingle with Celtic and Scottish/Irish influences, forming still another hybrid. The general feeling of sadness, loss and blues, which is inherent in the Scottish, Irish and Celtic roots anyway, together with an all new instrumentation could lay the basis ... |
What prevents a chimera's immune system from rejecting organs that developed from the other cell? | I'll refer you to [an earlier comment](_URL_0_) on this same topic, because I think the explanation is smashing.
I'd also like to emphasize looking further into the role of regulatory T-cells if this kind of research is of interest to you, because they're still a mysterious power in the human immune system.
For the sake of transparency, [here's](_URL_1_) the entire discussion. | [
"A proposed strategy to avoid cellular rejection is to induce donor non-responsiveness using hematopoietic chimerism. Donor stem cells are introduced into the bone marrow of the recipient, where they coexist with the recipient’s stem cells. The bone marrow stem cells give rise to cells of all hematopoietic lineages... |
What causes the opposite effects of size < -- > speed in gel-electrophoresis and size exclusion chromatography? | Watch these quick animations - should clear things up...
(Pulsed-field) Gel electrophoresis (PFGE):
[_URL_0_](_URL_0_)
& #x200B;
Size exclusion chromatography (SEC):
[_URL_1_](_URL_1_)
& #x200B;
In gel electrophoresis you're forcing all the molecules to go through the same (continuous) matrix (gel) by applying an electric current - think of the matrix as a bunch of different sized pores or holes, tunnels - smaller molecules can enter these pores and holes faster than bigger molecules that maybe need to find a bigger hole to progress in distance, finding bigger holes takes time, so bigger molecules move slower.
In size exclusion differs in that you don't have a continuous matrix, in reality, you have lots of little beads that have pores of different size themselves; but between the beads there is much bigger space (than the size of the pores of the beads) for liquid and particles to flow - in SEC you're typically not applying a current but you're using liquid flow. If you're a big particle you will not be able to enter the small pores of the beads and you fall through the cracks/space between the beads, so you're migrating faster than smaller molecules that can enter the pores (by diffusion) - so big particles come out first of the column of beads.
& #x200B;
"Interaction" - bascially what's meant by this is the following - because you're resolving over time, anything (interaction) that affects the speed at which your particles migrate will change their apparent (observable) molecular weight - even though they might not be as small/big as their retention time would indicate. This is because for example hydrophobic patches on a macromolecule (e.g. protein) can stick to the beads (i.e. NOT enter the beads, but just cling to them for a little bit in time). Hence these particular sticky proteins elute later as others, and will, therefore, appear smaller than their real molecular weight.
Hope this all makes sense. Animations help here a lot, so maybe browse around YouTube a bit :)
& #x200B;
& #x200B; | [
"Diffusiophoresis, by definition, moves colloidal particles, and so the applications of diffusiophoresis are to situations where we want to move colloidal particles. Colloidal particles are typically between 10 nanometres and a few micrometres in size. Simple diffusion of colloids is fast on lengthscales of a few m... |
How much of "the final solution" did German citizens and soldiers know about? | **Part 1**
> Most of them were just soldiers fighting a war they didnt wanna be in, right?
Not really. It's a fair assertion to say that virtually all Wehrmacht soldiers were aware of the atrocities that were committed, participated on some level in these atrocities and viewed most of it as legitimate.
I have previously wrote answers to similar questions [here](_URL_1_), [here](_URL_2_), and [here](_URL_3_) and it is not really possible to gauge the number of how many members of the Wehrmacht were directly involved in war crimes, not at least because the difficulty of establishing what "directly" means in this context: E.g. was a group of soldiers guarding an Einsatzgruppen mass shooting directly involved or not?
The question of how many knew of war crimes and what they knew of them is easier to answer, especially in light of the newer research by Felix Römer as well as Sönke Neitzel and Harald Welzer. They worked extensively with Allied protocols of conversations between German POWs recorded in Allied camps when they didn't think anybody was listening. Their research uncovered that knowledge of war crimes was ubiquitous among members of the Wehrmacht. Every soldier knew of atrocities that had been committed against Jews and other civilians because they had either been present, had participated or had been told about them by their comrades. During their time as POWs, they quite freely discussed these crimes. To exemplify this, Römer cites among others the following exchange between the Viennese Artillerie-Gefreitem Franz Ctorecka and the Panzer-Gefreiten Willi Eckenbach in August 1944 in Fort Hunt (translation my own):
> C: And then Lublin. There is a crematoria, a death camp. Sepp Dietrich is involved there. He was somehow caught up in this in Lublin.
>
> E: Near Berlin, they burned the corpses in one of these thingies ["einem Dings], the people were forced into this hall. This hall was wired with high-voltage power-lines and in the moment they switched on these lines, the people in the hall turned to ashes. But while still alive! The guy who was in charge of the burning told 'em: "Don't be afraid, I will fire you up!" He always made such quips. And then they found out that the guy who was in charge of burning the people also stole their gold teeth. Also other stuff like rings, jewellery etc.
[Römer, p. 435f.]
What this passage shows is that these Wehrmacht soldiers, who after all were both on the lower side of the ladder, being only Gefreite (lance corporals) were uncannily well informed even if the story about using electricity for executions wasn't true. But knowing not only of the Majdanek death camp near Lublin but also knowing about Sepp Dietirch's involvement proves them to be very well informed.
Or take this exchange between two Wehrmacht soldiers, Obergefreiter Karl Huber and Pioniersoldat Walter Gumlich, in Fort Hunt:
> H: One day, one guy just came and stole this Russian's cow and so the Russian defended himself. And then we had to hang fifty or a hundred men and women and let them hang there for three or four days. Or they had to dig a trench, line themselves up at the edge and were shot so they fell backwards into it. Fifty to a hundred people and more. That were the so-called "retributions". But that didn't help anything. Or when we set the village son fire [...] Partisans were naturally dangerous, we had to defend ourselves against them but this was something different [...]
>
> G: Ach, that were war operations. They [the people who did the above] are not really criminals.
>
> H: Exterminating whole families, shooting their kids etc., literally killing whole families? We are guilty if the military without any right or any order steals the last bread of some farmer.
>
> G: Oh, come on.
>
> H: Ach, don't defend them.
These and so many more conversations of this kind between Wehrmacht soldiers show that virtually every soldiers had either heard or seen these crimes if he had not participated in them himself. And given how numerous the crimes of the Nazis and the Wehrmacht were in the Soviet Union and elsewhere, this is hardly surprising. You already mentioned it in your expanded text above and I go into this in the linked answers but it is imperative to realize that the war against the Soviet Union was planned, conceptualized and fought as a war of annihilation, being in itself basically a huge war crime. Nobody is this fact more obvious than in the OKW's Kriegsgerichtsbarkeit Erlass, which actually forbid Wehrmacht soldiers from being persecuted for war crimes in the Soviet Union. That this was seen as necessary, tells you not just how deeply the Wehrmacht was involved but just what kind of war they planned to fight: One where combat operations and war crimes bled into each other seamlessly.
The background of this is touched upon in my linked answers as well as by Dr. Waitman Beorn in the linked AMA [here](_URL_0_).
Now when it comes to the question of rationalization, the protocols reviewed by Römer et. al. are also rather enlightening. As you might have noticed in the converstaion between Huber and Gumlich above, these crimes were sometimes regarded as controversial. Römer in his analysis proposes based on the protocols that Wehrmacht soldiers did indeed distinguish between what they viewed as legitimate and illegitimate violence.
Take this exchange Römer cites between soldier Friedrich Held and Obergefreiter Walter Langfeld about the topic of anti-Partisan warfare:
> H: Against Partisans, it is different. There, you look front and get shot in the back and then you turn around and get shot from the side. There simply is no Front.
>
> L: Yes, that's terrible. [...] But we did give them hell ["Wir haben sie ganz schön zur Sau gemacht"],
>
> H: Yeah, but we didn't get any. At most, we got their collaborators, the real Partisans, they shot themselves before they were captures. The collaborators, those we interrogated.
>
> L: But they too didn't get away alive.
>
> H: Naturally. And when they captured one of ours, they killed him too.
>
> L: You can't expect anything different. It's the usual [Wurscht ist Wurscht]
>
> H: But they were no soldiers but civilians.
>
> L: They fought for their homeland.
>
> H: But they were so deceitful...
[Römer, p. 424]
Römer uses this exchange to illustrate that even where there was a limited understanding for the Partisans and those who helped them (fighting for their homeland), as irregulars, they neither got nor deserved mercy. The Partisans were constructed by the Wehrmacht as dangerous, deceitful, and likely to shot them in the back. Violence against them and against civilians in general were justified and rationalized with this. Within this frame of reference, a lot of the most extreme violence committed by the Wehrmacht in occupied Europe was justified and for the soldiers, this view seemed natural and justified. They used it to justify and describe the most extreme atrocities and discussed them not as problems but rather with satisfaction. Fritz Kotenbeutel, a 24-year-old Wehrmacht soldier of an anti-Partisan unit speaks with great satisfaction of the good job they did burning down villages and executing every male they came across [Römer, p. 428].
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"On January 20, 1942, 15 high-ranking Nazi Party and German government officials met at a villa in Wannsee, a Berlin suburb, to coordinate the execution of the \"Final Solution\" (Endlösung) of the Jewish Question. At this Wannsee Conference, Reinhard Heydrich, Heinrich Himmler's deputy and head of the Reichssicher... |
What motivated the kamikaze? | By 1944 when kamikaze planes began to be used the Japanese defence ring had fallen apart and the Japanese began to understand that the only way out of the war was to inflict as many casualties upon the Americans as possible, in vain hope that the American public would grow war weary and force their government to sue for peace. This was the motivation shins the Kamikaze.
Now to understand why a pilot would be willing to sacrifice themselves on a suicide mission, you have to understand Japanese warrior culture. The Japanese samurai code of Bushido was considered important and every military personal would have known it. The code stresses loyalty unto death, it also stressed that to die in battle, in service to the emperor was the greatest honour a young man could bring to his family. To preform a successful kamikaze attack would bring great honour to your family, which was extremely important in Japanese society. To refuse to die in service of the emperor would have brought great shame and dishonour onto your house. Japan was a highly militarized society, so military acts were also looked upon with great respect and admiration.
That's what motivated the kamikaze, the idea that there death would serve the emperor and bring great honour to their family.
Source:
Japan's imperial army it's rise and fall by Edward drea
A history of japan by L.M Cullen | [
"While it is commonly perceived that volunteers signed up in droves for \"kamikaze\" missions, it has also been contended that there was extensive coercion and peer pressure involved in recruiting soldiers for the sacrifice. Their motivations in \"volunteering\" were complex and not simply about patriotism or bring... |
During WW2, were prisoners sent to war or did they continue their sentence? | Not to discourage further responses, but I answered a question some time ago [here](_URL_0_) that I'll repost below. | [
"In 1950, after most Allied war crimes trials had ended, thousands of convicted war criminals sat in prisons across Asia and Europe, detained in the countries where they had been convicted. Some executions had not yet been carried out, as Allied courts agreed to reexamine their verdicts. Sentences were reduced in s... |
Research questions regarding historic US census data | Here's tip - call them.
On three separate occasions, I have had to call the Census Bureau for information and on each occasion they have been incredibly helpful. I can say the same thing about the DOE.
It almost makes you feel good about the government. | [
"The National Historical Geographic Information System (NHGIS) is a historical GIS project to create and freely disseminate a database incorporating all available aggregate census information for the United States between 1790 and 2010. The project has created one of the largest collections in the world of statisti... |
How close is the Earth right now in its orbit as it was exactly one year ago? (In relation to the Sun) | (Assuming that by "year," you mean at midnight on 12/31 last year).
Well, the period that it takes Earth to orbit the sun is about 365.2564 days; since this was a leap year, this is a difference of about .7436 days. So we've gone .7436/365.2564 = .002036 extra orbits around the sun.
Now the distance to the sun is 149.6 million kilometers, so the length traveled during an orbit (fudging it a bit, since we really follow an ellipse) is 940.0 million kilometers.
Multiplying, the total difference is 1.913 million kilometers. In a normal year (not a leap year), it's about 1/3 of this, for about 640,000 km. | [
"Earth orbits the Sun at an average distance of 149.60 million km (92.96 million mi), and one complete orbit takes days (1 sidereal year), during which time Earth has traveled 940 million km (584 million mi). Earth's orbit has an eccentricity of 0.0167. Since the Sun constitutes 99.76% of the mass of the Sun–Earth... |
What are some good books regarding the transfer of Hong Kong? | Not a historian, but I did some historical economic analysis of Hong Kong under the British. I found these to be some useful sources. Not all of them cover modern history, but they're all comprehensive.
* A DOCUMENTARY HISTORY OF HONG KONG, GOVERNMENT AND POLITICS STEVE TSANG (HONG KONG UNIVERSITY PRESS) ISBN 9622093922
((This is probably your best bet))
* [Treaty of Nanjing 1842 - British Takeover](_URL_1_)
* [A Concise History of Hong Kong](_URL_0_)
* Edge of Empires: Chinese Elites and British Colonials in Hong Kong:John Carroll
* Hong Kong's History: State and Society Under Colonial Rule: Tak-Wing Ngo
Good luck
| [
"On television, Patterson presented a documentary about the transfer of sovereignty over Hong Kong, entitled \"Sir Les and the Great Chinese Takeaway\" (1997). He has appeared as a special guest on the following:\n",
"In the Joint Declaration, the People's Republic of China Government stated that it had decided t... |
How do birds know to make nests? Is it purely instinctual or is it taught? | It's both instinctive and learned, as with many complex behaviors. There's a review paper here, which is open-access and worth the read:
> It is possible that a bird comes into the world with a template that provides the basic information as to what a nest should be like and how it should be constructed, but uses feedback during the construction process to improve building performance. This might explain what appears to be practice nest building by the village weaver.
---[Nest building by birds](_URL_3_)
Other evidence for some learning:
> Given the diversity in nest building, it is perhaps surprising, then, that we know so little about how birds build nests. ... Historically, nest building was assumed to be independent of experience with nest material and nests. ... birds hand-reared in the absence of nest material and later exposed to nest material as adults, constructed nests resembling those built by experienced builders. ... One hundred and forty years on from Darwin and Wallace, there has been a surge in work on nest building in both free-living and captive birds, which is providing increasing experimental evidence for learning on selection of nest material.
--[From neurons to nests: nest-building behaviour as a model in behavioural and comparative neuroscience](_URL_0_)
> It is becoming apparent that birds learn from their own experiences of nest building. What is not clear is whether birds can learn from watching conspecifics build. ... Thus, first-time nest builders use social information and copy the nest material choices when demonstrators are familiar but not when they are strangers. The relationships between individuals therefore influence how nest-building expertise is socially transmitted in zebra finches.
--[Social learning in nest-building birds: a role for familiarity](_URL_2_)
> It is generally assumed that birds’ choice of structurally suitable materials for nest building is genetically predetermined. ... Our results represent two important advances: (i) birds choose nest material based on the structural properties of the material; (ii) nest material preference is not entirely genetically predetermined as both the type and amount of experience influences birds’ choices.
-[Physical cognition: birds learn the structural efficacy of nest material](_URL_1_) | [
"Many birds (and other animals) build nests. It can be argued that this behaviour constitutes tool use according to the definitions given above; the birds \"carry objects (twigs, leaves) for future use\", the shape of the formed nest prevents the eggs from rolling away and thereby \"extends the physical influence r... |
On average, how religious were the American founders, compared to average Americans? | They were clearly courting liberal positions for their era. They were far more educated the the average American so had ethical outlooks beyond religious books.
The concept of 'Life, Liberty and the pursuit of Happiness' simply flew in the face of the religious establisment. Persuing happiness was proposed by Englishman Locke as an ideal and was opposed by Protestant and Catholic ideologies, ie you persue the happiness of God.
Their 'religious tollerence' is very much liberal, as in Europe Catholics or Protestants were persecuted and discriminated against depending on who ruled their respective countries.
Now many of them were probably religious men, they probably were believers as such. But they would as a group see beyond the religious dogma of their own religion.
| [
"According to a 2002 survey by the Pew Research Center, nearly 6 in 10 Americans said that religion plays an important role in their lives, compared to 33% in Great Britain, 27% in Italy, 21% in Germany, 12% in Japan, and 11% in France. The survey report stated that the results showed America having a greater simil... |
how are we able to make decisions if everything follows the laws of physics | The idea of free will is sort of up for debate in my mind. If our thoughts, and therefore our decisions, are nothing but complex chemical signals in the brain, then they were predetermined by the thoughts that came before them, and before those, and the chemistry that happened in the womb to form the brain and the first thoughts, and all the physics and chemistry that happened before that all leading up to the current moment. Everything, including the birth and death of every star, planet, creature, and thought, was predetermined by the directions each subatomic particle flew in at the moment of the conception of the universe. Quantum uncertainty may play a role in free will, but nobody really knows right now. | [
"Other areas of decision theory are concerned with decisions that are difficult simply because of their complexity, or the complexity of the organization that has to make them. Individuals making decisions may be limited in resources or are boundedly rational (have finite time or intelligence); in such cases the is... |
why would there be a primary within the same party of the incumbent president seeking a 2nd term? | Cause maybe the party doesn't want the incumbent again or believes someone else has a better shot of winning. | [
"Including the special election in Arizona, Republicans will be defending 22 seats in 2020, while the Democratic Party will be defending 12 seats. Because the vice president of the United States has the power to break ties in the Senate, a Senate majority requires either 51 Senate seats without control of the vice ... |
Looking for some advice pertaining to teaching the Armenian Genocide. | As far as resources go, although it is a work in progress, a revamping of the WWI section of the booklist has been in the works recently, and the following are suggestions made by /u/yodatsracist and I which will at some point in the future be included, so this is a sneak peak.
*The Armenian Genocide: Evidence From the German Foreign Office Archives, 1915-1916* edited by Wolfgang Gust is an absolute must. It isn't the most *accessible* book, but it is the one I would point to to perhaps meet what you are looking for, as it is heavily based on primary sources which came from the German observers in the country, who were, obviously, allied to the Ottomans at the time, and can hardly be taken to have been antagonists.
*The Armenian Genocide: Cultural and Ethical Legacies* edited by Richard G. Hovannisian is a collection of writings by various authors, numbering over a dozen essays. I realize that anyone with an Armenian last name might not meet what you are looking for, but while Hovannisian is the editor, the contents reflect a wide array of contributors on many topics relating to the genocide.
*The Armenian Genocide: A Complete History* by Raymond Kévorkian. Again, I know this has the same "last name" issue, but it does a decent job living up to the title and being a thorough and compelling work that does an excellent job laying out the topic.
*"They Can Live in the Desert but Nowhere Else": A History of the Armenian Genocide* by Ronald Grigor Suny is a bit more basic, but great book for someone looking for a less hefty read, so probably more accessible a read than Kévorkian.
*America and the Armenian Genocide of 1915* by Jay Winter takes a more international look at the issue, as the Americans were neutral at the time and in the country. Academic in nature though, so might not be super accessible again.
*Denial of Violence: Ottoman Past, Turkish Present and Collective Violence against the Armenians, 1789-2009* by Müge Fatma Göçek. He is an historical sociologist covers early evidence of the Genocide (and other violence against Armenians, hence 1789) in Turkish sources, mainly memoirs, and also traces the history of the denial of that violence.
*The Making of Modern Turkey: Nation and State in Eastern Anatolia, 1913-1950* by Uğur Ümit Üngör. His his section on the Armenian Genocide doesn't break a ton of new ground, but he places it in the context of larger “social engineering” (that’s a key era for him and many of his Dutch contemporary Genocide studies) in the region. It’s about how what is and was an ethnically mixed region was brought definitively into and under control the Turkish nation-state. | [
"Kevorkian is the author of \"The Armenian Genocide: A Complete History\", \"an exhaustive and authoritative account of the origins, events, and consequences of the Armenian Genocide\". It was originally published in French in 2006. The book is the first to make extensive use of the archives of the Nubarian Library... |
How did people deal with mold on food before refrigerators in different time periods?? | First of all, while the refrigerator certainly did help, people used other means to cool food and keep food stored for long times. Ice coolers, where you would keep a block of ice in sawdust and have it replaced as it slowly thawed created cool spaces for the storage of food in Nordic countries' cities for a long time.
An [earthen cellar](_URL_0_) would often hold a temperature of slightly above modern refrigerator temperature in both summer and winter. It was also dark, which prevented various root crops from spurting.
My grandfather kept his home-grown potatoes in his earthen cellar well into the 1990s since it offered a large dark, dry and cool storage space.
Mold and rot grows from "free" water food. You can either bind the water with sugar or salt, or dry the food to create less "free" water and prevent the food from spoiling. Salting meat and fish was extremely common and is recorded from the earliest times we have any records in Sweden.
Baking dry Swedish cripsbread allowed people to store bread for a long time. Drying peas and beans allowed them to be stored for a long time.
Norwegian dried cod was an important trade goods, not only because it offered a safe source of protein that could be transported and stored and returned to a decent state by boiling, but also because it was allowed during lent in medieval catholic Europe.
Once sugar became more commonplace in the latter half of the 1800s, preserving berries and fruit by making preservatives such as jam or lemonade with lots of sugar became common.
Controlled fermentation was also a way to preserve foods - foods that ferment become sour and bacteria causing mold and rot do not like a low pH. Cheese, sourmilk and sourcream became ways to preserve milk and cream (as did salted butter) and fermenting grain to beer or grape juice to wine allowed one to store such goods for a long, long time.
Goods extremely high in fat are also resistant to mold and rot. Pressing rapeseed or olives to oil allowed one to store that as well.
Flour is dry, and can be stored for a long time, so people would bake bread a few times a week as needed.
Peasoup, a traditional Swedish dish is made from onions (could be stored in the earth cellar), dried yellow peas (could be stored for a long time) and salted pork (could also last a long time).
TL;DR Salt, sugar, fermentation, drying, earth cellars. | [
"Prevention of mold exposure from food is generally to consume food that has no mold growths on it. Also, mold growth in the first place can be prevented by the same concept of mold growth, assessment, and remediation that prevents air exposure. In addition, it is especially useful to clean the inside of the refrig... |
What was the transition like from the Hapsburgs to the Bourbons in Spain? | In what sense? The actual transition between ruling dynasties was bloody and very messy: the War of Spanish Succession was fought between the major powers of Europe over whether a Bourbon - and, more importantly, Louis XIV's grandson - should be allowed to ascend to the Spanish throne. But are you talking about that war, or institutional and societal changes as a result of the transition? | [
"The prospect of Bourbons on both the French and Spanish thrones was resisted as creating an imbalance of power in Europe by its dominant regimes and, upon Charles II's death on 1 November 1700, a Grand Alliance of European nations united against Philip. This was known as the War of Spanish Succession. In the Treat... |
Is Neil Armstrong's first foot print still on the Moon or have forces and events removed it? | > The biggest question for me that I do not have the answer is how careful were the astronauts when leaving and re-entering the Eagle lunar lander to make sure that Neil Armstrong's first footprint was not damaged.
They weren't careful at all. The first footprint was likely obliterated within minutes of it being made, possibly seconds. Between Aldrin and Armstrong, they likely trampled it to the point of not being visible at all.
The tracks from the first (and subsequent) Lunar EVA are still visible, however. See, e.g., the [fascinating pictures from the Lunar Reconnaissance Orbiter](_URL_0_). | [
"On August 25, 2012, the BottomLine was used to acknowledge the death of astronaut Neil Armstrong, the first man to walk on the moon. It was reportedly only the fifth of six times that an outside news event not involving an athlete was reported on the ticker, alongside the news of the September 11 attacks, the deat... |
who invented the thumbs up compliment? and how long has it been around? | One popular explanation is that during the height of the Roman empire, Gladiators would turn to the guests of honor on whether or whether not to kill their opponents or beasts.
The thumbs-up, or thumbs-down would symbolize the weapon coming down, or staying above the defeated combatant's head.
Also, it also comes from the fact that during the Dark ages, personal seals were marked down using the thumb, so a thumb itself would represent agreement and trust.
It was probably popularized during the second World War where there are reports of both American and Chinese fighter pilots using it as "okay, ready to go" or as sign of respect respectively. | [
"The \"Oxford English Dictionary\" cites the earliest written instance of \"thumbs-up\" (with a positive meaning) as being from \"Over the Top\", a 1917 book written by Arthur Guy Empey. Empey was an American who served in the British armed forces during World War I. He wrote: \"Thumbs up, Tommy’s expression which ... |
If the fluoride in toothpaste helps teeth by contact, how does the fluoride in water help if it only briefly comes in contact? | The fluoride in water is incorporated into the developing teeth of children and makes the enamel stronger and more resistant to decay. The fluoride in toothpaste works on contact to help remineralize weak areas. | [
"Fluoride is a natural mineral that naturally occurs throughout the world – it is also the active ingredient of many toothpastes specifically for its remineralizing effects on enamel, often repairing the tooth surface and reducing the risk of caries.\n",
"Despite fluoridation's detractors, most dental professiona... |
why do credit cards give airline miles? | The biggest credit card spenders are business travelers with expense accounts. That expensive business class ticket? They buy it. $15 hotel wifi? No problem. Expensive meal at a restaurant? Bring it on. They spend all that money on their credit card, and the company reimburses them for it. Plus they get to keep any airline points.
Credit card companies and airlines have realized this. They realized that if business people are going to be taking expensive fares and often, they want to hook them on their airline and card. The best credit cards and airline perks go to these spenders because once they get status on one particular airline or card, they're hooked. They might even take more expensive flights (and charge the client/business) in order to get points on their airline/card.
This business traveler is the target market for both credit card companies and airlines (and hotels to a lesser extent.) That's why they tend to link them together. | [
"Western officials traced the problem to difficulties with credit card payments. The company had been running into problems obtaining a merchant identification number, which was needed before banks would deposit money into the airline's account. The airline stated it was working out an arrangement with PayPal, whic... |
how do doorbells work? | So traditional wired doorbells are normally simply a complete wired circuit involving:
- a bell
- a transformer to lower the voltage so that if the button gets compromised people won’t get a high voltage shock by pressing the button
- a button outside
- and wiring connecting it all
When you press the button outside it completes the circuit by allowing electricity to pass through and ring the bell. | [
"A doorbell is a signaling device typically placed near a door to a building's entrance. When a visitor presses a button the bell rings inside the building, alerting the occupant to the presence of the visitor. Although the first doorbells were mechanical, activated by pulling a cord, modern doorbells are electric,... |
Monday Methods: History Pedagogy (The Theory and Practice of Teaching and Learning) | Great work!
I particularly appreciate the section on the obsession with "coverage." Too many times have I seen educators at both HS and collegiate level get obsessed with teaching it all (as if possible).
I always suggest the method of creating your class topics last in developing your course structure. Start with your class goals (3-5). An example might be the following: Students will be able to recognize interactions between humans and their environment and how they shape history. Although broad, it guides the goals of each lecture/lesson. I also suggest marking down some " subthemes" you want to cover. Something like, commodification, changing distance, animal extinction/destruction, etc.
Next you can write down topics in your course period/location/field which can drawn out important aspects of the goal. For example, the following might be a few topics for the previous goal if used in a US History II course: transcontinental railroad, buffalo, railroads and cattle/meatpacking, conservation of Progressive era, influenza, dust bowl, suburbanization, car culture, interstate highway system, and many more. Next you limit yourself or combine some of these.
After you have topics selected, make an essential question for the topic. Something that is specific to the topic, but stated in a way that could be applied to other topics, too. For the topic "conservation," you could ask, "What were the historical actors goals for the use of 'nature' and who was to benefit from that use?" Note, question is one related to historiographical discussions and might even have a particular work in mind. (Looking at you *Conservation and the Gospel of Efficiency*)
Now you are in a position such that one of your class topics is progressive era conservation and you have a guiding question that, hopefully, is one students might be intrinsically interested in. You can now make a lesson based on that question. Use images, primary source documents, discussion, etc to leave behind lecture. | [
"Critical pedagogy explores the dialogic relationships between teaching and learning. Its proponents claim that it is a continuous process of what they call \"unlearning\", \"learning\", and \"relearning\", \"reflection\", \"evaluation\", and the effect that these actions have on the students, in particular student... |
are there any disorders that involve an altered perception of the rate of time? | [This might interest you.](_URL_0_)
I know at the least some disorders cause you to "lose" time in the sense that you blacked out and can't remember what you did.
I'm just adding useless text to my comment here because for some reason this sub thinks you cannot give a concise and meaningful answer. Must have long winded mods or something. I also think this might be better suited to /r/askscience. | [
"Along with other perceptual abnormalities, it has been noted by psychologists that schizophrenia patients have an altered sense of time. This was first described in psychology by Minkowski in 1927. Many schizophrenic patients stop perceiving time as a flow of causally linked events. It has been suggested that ther... |
how does a full cycle charge extend a lithium-ion batteries life? | It's not required for the battery at all.
You know how the battery meter on your phone or whatever says 100% right when you take it off? And 57% sometime later? It needs to be calibrated to accurately determine from the battery (usually via a voltage measurement) what the state of charge is.
Doing a full cycle occasionally helps your device do this calibration.
Note, with a Li battery, you DON'T need to do this very often (certainly no more than monthly). Fully discharging the battery can actually damage it, unlike older NiMH or NiCd batteries. | [
"Battery cycle life is most commonly specified at a discharge depth of 80 percent of rated capacity and assuming a one-hour discharge current rate. As the discharge current or the depth of discharge is reduced, the number of charge-discharge cycles for a battery increases. When comparing NiZn to other battery techn... |
Which interactions can explain that EtOH (Alcohol) has a way lower freezing point than H2O? | The same exact processes apply. The way you should look at it when compared to the boiling point is seeing the freezing point as a melting point instead.
Just like water has a higher boiling point than ethanol, it also has a higher melting point. | [
"As a derivative of methanol, triphenylmethanol is expected to have a p\"K\" in the range of 16-19. Typical of alcohols, resonance offers no stabilization of the conjugate base due to being bonded to a saturated carbon atom. Stabilization of the anion by solvation forces is largely ineffective due to the steric inf... |
What's going to happen to the polar bears as the ice caps shrink? Evolution or extinction? | Well extinction is a distinct possibility as a loss of sea ice results in very large evolutionary hurdles. On the other hand with less ice and snow, selection pressures favour darker bears, and as they can interbreed with grizzlies its possible they might just converge back into a single species. | [
"Four months later, the United States Geological Survey completed a year-long study which concluded in part that the floating Arctic sea ice will continue its rapid shrinkage over the next 50 years, consequently wiping out much of the polar bear habitat. The bears would disappear from Alaska, but would continue to ... |
what is a scripting language? | A scripting language is a type of programming language, it's normally not compiled before being run and normally is created or modified by end-users. It also normally is used to interact with other applications, as opposed to creating an application itself. | [
"A scripting or script language is a programming language for a special run-time environment that automates the execution of tasks; the tasks could alternatively be executed one-by-one by a human operator. Scripting languages are often interpreted (rather than compiled).\n",
"A scripting language is a high-level ... |
If some tectonic plates are subducting under one another, is it possible for a whole landmass to be forced underneath when it reaches the boundary? | Subduction zones feature oceanic plates (usually old and cold oceanic plates) sinking into the mantle. I say "sinking" because that is literally what is going on. Oceanic plates are high density, especially when they are old and cold, and when they enter subduction zones they sink very slowly through the solid mantle. Continental plates are difficult to subduct because they are low density. They float on the mantle. When a bit of continental material enters a subduction zone it is often scraped off and accreted to the overriding plate instead of going down the trench. | [
"The theory of plate tectonics states that the Earth's crust is made up of rigid plates that \"float\" on top of the mantle and move relative to one another. As the plates move, the crust deforms dominantly along the plate margins. Intraplate deformation differs from that respect by the observation that deformation... |
What sort of building materials might we fnd and utelize on mars? | The first intended use of *in situ* resources will be using water on Mars for human consumption and breathable air, along with separating the hydrogen and oxygen for fuel. For habitation we will start with units sent from Earth and use local materials for radiation shielding (as shells surrounding the prefab units for example). A lot of experimentation will have to be done "on the ground" before we would trust direct life support functions to native materials.
There's a NASA-chaired [In-Situ Resource Utilization (ISRU) Capability Roadmap Progress Review](_URL_0_) (6MB PDF) from 2005 that gives a good general overview of the subject. | [
"In situ resource utilization involves using materials encountered on Mars to produce materials needed. One idea for supporting a Mars habitat is to extract subterranean water, which with sufficient power could then be split into hydrogen and oxygen, with the intention of mixing the oxygen with nitrogen and argon f... |
Looking for European history books written by non-Westerners. What's a good place to start? | This isn't exactly what you are looking for, but your question reminded me of the [Chinese fascination with Jews](_URL_0_). It is very interesting to see how an entirely foreign culture view a culture that is more familiar to us. It also makes you wonder how accurate and fair Western historians actually are when they turn their gaze away from their own cultures. I suspect that much like the Chinese towards the Jews, we tend to either fetishize or simplify foreign history when viewed through our Western eyes. | [
"The guidebooks have received much praise in the international media. The \"Wall Street Journal\" described the style as \"tongue-in-cheek advice\" with \"brutal honesty\". The \"International Herald Tribune\" described them as \"an Eastern European publishing phenomenon\" and \"The Times\" wrote that they are \"Th... |
What makes certain stainless steels non-magnetic? | My metallurgy teacher would murder me for this answer, but here's the basics.
Regular steels at normal temperatures exist in the crystalline state martensite. When heated above a temperature (*which is defined by the alloying elements in the steel*), the crystal structure breaks down, and the steel's structure becomes austenite. This temperature is usually very high, but much lower than melting point for the steel.
The non-magnetic steels you describe are in the austinitic structure, but large amounts of other elements (chromium and nickel, for the most part) allow this structure to exist at all temperatures below melting point.
The normal steels, at room temperature, have the iron molecules arranged in an alpha-phase, which is like a cube with an extra particle in the centre. This structure is typical to most steels, and is magnetic.
Above the critical temperature, the steel shifts to gamma-phase, which is like a cube with a plus-sign inside it ([kind of](_URL_0_), alpha on left and gamma on right). This structure is much more resistant to alighment of magnetic moment.
(if anyone who has a better understanding wants to hit me up, please do so.) | [
"Stainless steels are used extensively in these industries for their corrosion resistance to both aqueous, gaseous and high temperature environments, their mechanical properties at all temperatures from cryogenic to the very high, and occasionally for other special physical properties.\n",
"Stainless steels conta... |
Can a Neutron star and a black hole be in the same star system? | It is possible, but none have been detected. | [
"Binary systems containing neutron stars often emit X-rays, which are emitted by hot gas as it falls towards the surface of the neutron star. The source of the gas is the companion star, the outer layers of which can be stripped off by the gravitational force of the neutron star if the two stars are sufficiently cl... |
how are cancer and tumors related? does one cause another? | Tumors are cells that are ignoring only some of the rules the body sets for them. Cancer cells have gone completely renegade.
Specifically, the body sets clear rules for which cells are allowed to divide (and thus grow their tissue) and when. That's how you grow and maintain your organs and other bodily tissues. If cells were allowed to divide whenever they wanted to, you'd end up with strange bulbous growths that would leech blood and nutrients while making a mess of things and getting in everyone's way. Sound familiar? Yes, that's a tumor.
Tumors aren't necessarily that harmful as long as they aren't messing things up too much. If they are small, self-contained, and in a place where they can't do much harm, you can live with a tumor for a very long time without serious complaints. If they are larger or if they are interfering with vital functions, a tumor may become a problem in and of itself and have to be removed for that reason.
A more important issue, though, is that cells who've already broken some of the body's rules may start breaking others. Specifically: the very important rule that, with some exceptions (e.g. blood), cells need to stay in their designated place within the body. When cells break this rule as well, we call them *malignant* or *cancerous.* These cells are now traveling throughout the body and settling in different places, where they start dividing again and growing new tumors. This is very bad. As I said, you can live with a contained tumor quite happily if it isn't interfering with anything important. But if tumors start to grow everywhere, that's a different ball game. Some of these tumors are bound to be in dangerous places, and even if they aren't, their numbers alone can start to pose a problem.
Moreover, once you're at this stage, it becomes much harder to remove the bad cells. A single, large-ish tumor can be easily detected, surgically removed, irradiated, or otherwise targeted specifically. But once you have many small tumors growing all over the place, you're fighting a guerrilla war. The enemy is now spread over many places, and hard to track. We're getting better and better at fighting these sorts of wars, and we can subdue cancers for longer and longer, to the point where more and more people are dying *with* cancer, not *of* it. But it all depends on how far the cancer has spread, as well as the type of cancer and how aggressive it is. In any case, the earlier you detect it, the better, and often a *benign* (i.e. not (yet) cancerous) tumor will be removed for that reason. | [
"A tumor is an abnormal growth of body tissue. In the beginning, tumors can be noncancerous, but if they become malignant, they are cancerous. In general, they appear when there is a problem with cellular division. Problems with the body's immune system can lead to tumors.\n",
"This is a list of cancer types. Can... |
why does metal shrink & water expand when they turn from a liquid to a solid? | Water molecules stick together through hydrogen bonding. In a liquid state, there is enough kinetic energy (heat) in the molecules to prevent stable hydrogen bonds from forming, so they form and break as molecules flow over each other. As water loses heat (remember, kinetic energy) they are able to move closer together because they bump into each other less, and at 4 degrees C water is most dense - and a liquid - because there's still too much kinetic energy for them to form stable hydrogen bonds, but not enough for molecules to force each other apart. Heating or cooling beyond this point causes water to expand.
When enough heat is removed, water can begin forming stable hydrogen bonds. This forces molecules to form sort of rings with a lot of empty space in between them. Compare the structure of [ice](_URL_1_) to [liquid water](_URL_0_).
Most other things, however, don't have so much space in their solid structure. As they lose heat, they move less, and thus bump into each other less and become more dense as they are able to move closer together, and becoming more dense = contracting. | [
"Most metals and alloys shrink as the material changes from a liquid state to a solid state. Therefore, if liquid material is not available to compensate for this shrinkage a \"shrinkage defect\" forms. When progressive solidification dominates over directional solidification a shrinkage defect will form.\n",
"Ab... |
how do micronutrients work? are they a good solution to malnutrition in poor countries? | Micronutrients refer to the nutritional value of a food, e.g. vitamins and minerals
Macro nutrients refer to the nutritional content of food, e.g. Protein, carbohydrate and fat
Micronutrients would help if the said person was deficient in vitamins due to a diet that isn't varied, however if the said person if deficient in food all together then micronutrients wouldn't do much to help as they would be deficient in macronutrients and therefore calories which are all essential to normal function of the body. | [
"Nutrition International, formerly the Micronutrient Initiative (MI), is an international not for profit agency based in Canada that works to eliminate vitamin and mineral deficiencies in developing countries. Although often only required by the body in very small amounts, vitamin and minerals – also known as micro... |
Is it possible for a dark object to be moved by a bright enough flash of light? | Yes, light has momentum. When light hits an object and is absorbed or reflected, under conservation of momentum the object has to gain some small amount of momentum.
see also:
- _URL_1_
- _URL_0_
| [
"According to Prof Leonhardt, all optical illusions can slow down rays of light and the sphere can be used to bend this illusion around an object, reflecting off it and making it appear to be invisible. Mr Perczel added: \"When the light is bent it engulfs the object, much like water covering a rock sitting in a ri... |
Is there an object that floats on moving water but sinks otherwhise? | Sure, if you count floating as staying at some constant level in the water. The floating wouldn't be caused by only buoyancy, it has to be some combination of buoyancy and lift.
You can generate lift in water with hydrofoils. | [
"A floating object will seek the highest point of the membrane and thus will find its way to either the center or the edge. A similar argument explains why bubbles on surfaces attract each other: a single bubble raises the liquid level locally causing other bubbles in the area to be attracted to it. Dense objects, ... |
- what exactly is the current relationship between the us and cuba, and why does it appear that the relations haven't changed much despite the end of the cold war? | When Castro came to power, may Cubans fled to Florida, and harbored a deep seated hatred for Castro, one they handed down to their children and grandchildren. So now there is this huge community of rabid anti-Castro voters living in the biggest swing state in the US.
During the Cold War, this served US interests well, but now it complicates matters. Even though there are a a lot of Americans who feel the US should normalize relations with Cuba, it is not something many people are passionate about. On the other hand, the anti-Catro community would raise holy hell, to the point any political party that suggest it would risk losing the Florida vote. At the end of the day, there is very little to be gained politically, and a lot to lose, by softening the relationship with Cuba. | [
"Over time, the United States' laws and foreign policy regarding Cuba has changed drastically due to strained relationship. Beginning with opposition to the Castro led Independence Revolution in Cuba, the Spanish–American War, naval use of Guantanamo Bay, trade restrictions imposed by Nixon, and a trade embargo ope... |
If you're stuck in a fire, is it a good idea or a bad one to douse yourself with water? | I'm not a scientist - so I'm not sure if I'll be welcoming the downvote brigades - however, I am a certified Fire Fighter and Fire Safety Officer, so I can chip in with a bit of 'actually been inside a burning house' experience.
Firstly, from a structural standpoint - the steam that comes from throwing water on a fire can cook you just as fast as the fire itself. It's hot, it's blustery, and it's absolutely terrible. So you're instructed to keep your hose on a [straight stream](_URL_1_) to discourage the steam from falling down on you, and cooking you alive in your suit.
However, if it starts to heat up in there, we're instructed to lay on our backs, and shoot a [fog pattern](_URL_3_) directly up to act as a barrier between us and the fire.
But, if you find yourself in a burning house - stay low (Heat/smoke rises) and make for an exit by any means necessary. You can also wet a cloth to hold over your face to protect a bit from the smoke.
However if it's just you and the fire in the room, with no method of escape - you're not going to last very long at all. Even under proper protection, it gets hot enough to melt plastic in your wallet.
Now - the wildfire standpoint is more interesting.
A common technique is to [run to the nearest river](_URL_2_) and wait out the fire as it burns over you, while you dose yourself down continuously.
Wildland fire apparatus - as you'd find in hotter places like Australia - have something called a [Halo Burnover Protection System](_URL_0_) which basically cascades water over the truck in the event of a burnover - which is when the wind blows the fire over the truck, and the fire 'burns over' the apparatus.
A more crazy technique to avoid being burnt to death in a wildland setting - and something that usually only works with a fast moving or prairie fire - is a method called an 'escape fire'.
Basically you burn a 20-foot-wide patch to the ground in advance of the fire. You then hunker down in the middle so when it burns over you, there's nothing near you that will ignite.
There's a lot of many and varied techniques to avoid wildfires - but they generally remain the same. When fit hits the shan, find water, stay low, stay wet, and hope for the best.
There's a really awesome documentary on the Black Saturday Bush fires in Australia called 'Inside the Firestorm', if you want to hear actual survivals stories and see how terrifying brushfires really are.
**TL;DR - Lots of fire survival techniques/information** | [
"Use of water in fire fighting should also take into account the hazards of a steam explosion, which may occur when water is used on very hot fires in confined spaces, and of a hydrogen explosion, when substances which react with water, such as certain metals or hot carbon such as coal, charcoal, or coke graphite, ... |
when i call someone, why is the first ring always louder than subsequent rings? | This is probably due to sensory adaptation. When you experience something that triggers one of your senses multiple times in a row, the experience is less and less each time. This is also why you get used to smells. | [
"The ringing tone is often also called \"ringback tone\". However, in formal telecommunication specifications that originate in the Bell System in North America, ringback has a different definition. It is a signal used to recall either an operator or a customer at the originating end of an established telephone cal... |
Are there Babylonian or Sumerian myths that could have inspired the myth of Moses, like how there are for Noah's Ark? | Sargon of Akkad was supposedly found in a basket in a Mesopotamian river. (Roux, *Ancient Iraq*) | [
"The Boatman of the title \"is Noah, but both Noah and the ark itself form an allegory for the artist and the artistic experience, the ark representing Jung's collective unconscious.\" \"The creation is inside its creator, and the ark similarly attempts to explain to Noah ... that it is really inside him, as Eve wa... |
When did relations between Native Americans and white settler/travelers turn from friendly trade to violent outbursts? | Hello there. Unfortunately we have had to remove your question as it looks like it may be a homework question. A couple of things to keep in mind about this: [Our rules](_URL_0_) DO permit people to ask for help with their homework, so long as they are seeking clarification or resources, rather than the answer itself. Also: Sometimes flairs can be reluctant to answer a question that looks like homework, because they don't want to be involved in plagiarism (and sadly, yes, there are those who plagiarize reddit comments).
But, that all said, many of our users do enjoy helping out with suggestions for resources and further reading. Can you tell us what you've researched so far, what resources you've consulted, and what you've learned? If that doesn't work, you can also consider asking the helpful people at /r/HomeworkHelp. If you edit your post to be in compliance with our requirements for homework related questions, which are explored in more detail in this [META Thread](_URL_1_), we would be happy to restore it.
Additionally, we would highly suggest that you check out our six part series on '[Finding and Understanding Sources](_URL_2_)', which might prove to be useful in your research. | [
"Initially, there were peaceful interactions with Native Americans. Chiefs Washington and Colorow led their tribes along Sulphur Gulch, passing and sometimes visiting cabins of early settlers, like John and Elizabeth Tallman. During one visit, Chief Washington offered up to 20 ponies in trade for their red-headed s... |
Help/suggestions on what books to read pertaining to ancient Syrian history. | Caveat: I am most familiar with the history of Syria prior to the Achaemenid period, and my reading recommendations reflect that.
# **HISTORICAL OVERVIEWS**
*Ancient Syria: A Three Thousand Year History* by Trevor Bryce is a good first introduction. Bryce relies too heavily on textual sources at the expense of archaeological data, but it's the most readable narrative history of ancient Syria I've read so far.
*Syria 3000 to 300 B.C.: A Handbook of Political History* by Horst Klengel is the most detailed overview of the political history of ancient Syria, though it's badly in need of an updated edition.
# **ART AND ARCHAEOLOGY**
*Ebla to Damascus: Art and Archaeology of Ancient Syria* is a pretty decent introduction to art from ancient Syria. It's best used in conjunction with the more detailed *The Archaeology of Syria* by Akkermans and Schwartz.
Also see the series of beautifully photographed catalogues produced by the Metropolitan Museum:
* [*Art of the First Cities: The Third Millennium B.C. from the Mediterranean to the Indus*](_URL_0_)
* [*Beyond Babylon: Art, Trade, and Diplomacy in the Second Millennium B.C.*](_URL_1_)
* *Assyria to Iberia at the Dawn of the Classical Age*
# **BRONZE AGE**
Wilhelm's *The Hurrians* remains the best monograph on the Hurrians, though it cannot be emphasized enough that our knowledge of Hurrian history and language have advanced considerably since its publication in 1989; Neu's 1996 publication of the Hittite-Hurrian bilingual and the excavations at Urkesh since 1984 have been particularly important developments.
*Mari and Karana: Two Old Babylonian Cities* is an extremely readable introduction to two of the most important sites in Syria (as a heads up, many scholars now identify Tell al-Rimah as Qattara, not Karana). Sasson's *From the Mari Archives* contains a fascinating collection of the most interesting letters from Mari.
Ugarit, the most important site in Syria in the Late Bronze Age, has an extensive bibliography. Yon's *The City of Ugarit at Tell Ras Shamra* and *Ugarit: Ras Shamra* by Adrian Curtis are the best places to start. Itamar Singer's detailed political history of Ugarit is available in *Handbook of Ugaritic Studies* as well as *The Calm Before the Storm: Selected Writings of Itamar Singer on the End of the Late Bronze Age in Anatolia and the Levant*.
For the contemporary site of Emar, see Chavalas' edited volume *Emar: The History, Religion, and Culture of a Syrian Town in the Late Bronze Age*.
# **IRON AGE**
Lipinski's *The Aramaeans: Their Ancient History, Culture, Religion*, Niehr's *The Aramaeans in Ancient Syria*, and Younger's *A Political History of the Arameans* are the best overviews of the Aramaeans, but they're probably more detailed and expensive than you're looking for.
For the Neo-Hittite kingdoms, there's Melchert's edited volume *The Luwians*, now heavily out of date in places, and Trevor Bryce's *The World of Neo-Hittite Kingdoms*.
I also recommend the video lecture [The Syro-Anatolian City States: A Neglected Iron Age Culture](_URL_2_), courtesy of the Oriental Institute in Chicago.
# **OTHER RESOURCES**
The standard ANE resources contain a lot of good information about ancient Syria.
* *Civilizations of the Ancient Near East* (4 volumes) edited by Jack Sasson
* *The Oxford Handbook of the Archaeology of the Levant* edited by Killebrew and Steiner
* *A Companion to the Archaeology of the Ancient Near East* (2 volumes) edited by Daniel Potts
* *The Ancient Near East: History, Society and Economy* by Mario Liverani
| [
"Syria, subtitled \"Archéologie, art et histoire\" (until 2005 \"Revue d’art oriental et d’archéologie\"), is a multidisciplinary and multilingual academic journal covering the Semitic Middle East from prehistory to the Islamic conquest. It is published by the Institut français du Proche-Orient and was established ... |
why are certain eye colors almost none existent? (like purple) | Only time I have seen "red" is with albinos. You see red because of the complete absence of pigment which allows for a good reflection of their retina in the correct lighting conditions. This lack of pigment also means that they tend to be very sensitive to light (a lot of albinos are nearly blind).
Eye color is mainly a function of the pigment melanin. If your eyes have a lot of it, they're brown. If they don't, they're blue. (Some details of this explanation are in dispute, but don't worry about that now.) Green eyes result from yellowish flecks of fatty pigment against a dark background. Some men think a green-eyed woman is exotic. The truth is she's got fat eyes.
I have never seen purple eyes. Animals maybe? Then I assume it's the same idea but different colours (different pigment). | [
"The phenomenon is not entirely understood. One possible reason people see colors may be that the color receptors in the human eye respond at different rates to red, green, and blue. More specifically, the latencies of the center and the surrounding mechanisms differ for the different types of color-specific gangli... |
Why were the religions in the British Isles so divided? | Firstly, Scotland is in Britain. On the map, England is marked as Anglican (and Wales isn't marked at all, but then, from a legal standpoint Henry VIII had made Wales part of "The Realm of England")
Secondly... why shouldn't they be different? They were different countries, with different histories. Scotland and England(/Wales) were ancient foes, having fought many wars (within living memory) and the Queen of England in 1600 (Elizabeth I) had actually imprisoned and eventually executed the Scottish King's own mother (and former Queen of Scotland).
More to the point, they'd had quite a different transition from Catholicism to Protestantism. Scotland was slowly influenced by various continental protestants, and the number of Protestants grew. A fiery preacher called John Knox popularised the Calvinist form of Protestantism. Several Protestant Lairds (lords), who called themselves the "Lords of the Congregation" became quite powerful, and got the Scottish parliament to adopt Protestantism. When a weak Queen Mary returned from France (her husband, the King of France, having died), Protestant Lords forced various concessions from her and eventually made her abdicate in favour of her young son, who was then raised as a Protestant.
(A note: while that map describes Scotland as Calvinist, the Church is actually called the Presbyterian Church, not the Calvinist Church. But their theology is broadly Calvinist.)
The English Church became Protestant in quite a different way. Henry VIII was fed up with Papal control for various reasons (most famously because he wanted a divorce and the Pope wouldn't grant it to him), and "reformers" (ie people interested in Protestant ideas) gained influence with him by suggesting he declare himself head of the English Church, not the Pope. This was eventually done, allowing Henry to get his divorce, as well as dissolve the monasteries and get their money.
So, unlike Protestantism in Scotland, which was essentially just the normal spread of Protestantism in its Calvinist form, Anglicanism was a top-down reform of the English Church to take it out of the Pope's control. Exactly how similar the Church of England should be to Catholicism, Calvinism or Lutheranism is something that was very contraversial in England, and was a strong influence in 17th century politics. In fact, even today there are "Anglo-Catholic" churches (aka "High" Churches) and "evangelical" churches, Calvinists and Arminians, conservative Christians and liberal Christians, all within the Church of England. It's probably one of the most theologically diverse Church denominations, to the extent that it's sometimes not even classified as a Protestant church at all.
But wait, one might ask, what of Ireland? In 1600, England and Scotland were two entirely seperate realms (this would change 3 years later), but Elizabeth I of England was also Elizabeth I of Ireland.
But that's not something that the Irish approved of; the Irish chiefs had only accepted Henry VIII as King of Ireland because he invaded* and forced them to. In fact, in response to English attempts to reform the Irish Church to be more Protestant, settle English protestants in the Pale (an area under English law in eastern Ireland; it's the origin of the phrase that something is "beyond the Pale"), and general anger at paying taxes to a foreign ruler, there was a large rebellion in northern Ireland called the 9-Year War. This led with the Irish chieftains of that region losing, and their land being settled by Protestants (the origin of today's Protestant/Catholic rivalry in Northern Ireland).
To the Irish, Protestantism wasn't a new radicalism discussed by the educated middle-classes, opposed to the corrupt establishment Church, as it seemed to many Englishmen and Scots; to the Irish, Protestantism was the corrupt church of their evil English oppressors. Thus, Catholicism became a mark of true Irish patriots fighting against the heretical English oppressor. And thus, while Protestantism was common amongst the Anglo-Irish nobility, it made little inroads amongst regular Irish people.
*The Kings of England had styled themselves "Lords of Ireland" for centuries, since the Norman invasion of Ireland had forced the Irish Kings to acknowledge English overlordship, but in the century prior to Henry VIII's invasion they'd had little real, practical power over Ireland. | [
"The predominant religious tradition of the island is Christianity. Before the Protestant Reformation, the island had a long history as part of the unified Western Church, and in the years following the Reformation, the religious authorities on the island, and later the population of the island, accepted the religi... |
Happy 2nd Birthday, AskHistorians! | > Your favorite askhistorians moment
Four words: April. Fools. Rule. Changes.
That was fantastic. | [
"Happy Birthday was written and composed by Japanese Hip-hop artist SEAMO. \"Happy Birthday\" reached the number-one spot on both the daily and weekly Oricon charts, selling 201,304 copies in its first week; just 38 more copies than their previous single Summer Time, which sold 201,266 copies in its first week.\n",... |
Why does something made of iron smell? | Iron is constantly oxidizing with oxygen it comes into contact with. It is vaporizing, but very slowly. It's why rust happens, and why rust is much less dense than iron; some of it has turned to gas.
Almost the same thing happens with pennies, only with oils. You know that copper-y smell that pennies have? That's the copper and other metals in it reacting with oils in your skin. Pick a penny up with a tissue or cloth, and there's no noticeable smell. | [
"The study of odors is complicated by the complex chemistry taking place at the moment of a smell sensation. For example, iron-containing metallic objects are perceived to have a distinctive odor when touched, although iron's vapor pressure is negligible. According to a 2006 study, this smell is the result of aldeh... |
what safety measures are on gas tanks to prevent them exploding when a car is on fire? | Usually seal them so oxygen cannot get to the gas and contribute.
On a science note, gasoline vapor is explosive and flammable, not so much liquid gasoline. So as long as the gas is condensed into a liquid and kept contained, it's quite safe. Which is also why you should never take the nozzle out of the tank if there is a fire while filling. The lack of oxygen will smother the fire while "heroically " removing the nozzle will cause a significantly worse fire. And total loss of the car, if not the station and other vehicles. | [
"The fire department was in the process of setting up a deluge gun to cool the car, which would have delivered far more water than the booster attack lines they initially were using; however, before the deluge gun could be made ready, the pressure inside the tank car reached the design bursting limit and the tank c... |
When did the language of French become the majority language of France? | I cant speak on the validity of the 20% comment , however, french became the language of France during the French Revoloution. Before French borders became much more realized during the end of the 18th century, France was composed of french, flemish, german, italian, among other languages. By 1795, the national convention instituted state funded schools, part of the doctrine was that all schools be taught only in french. By the time Napoleon came to power, french was seen as a national language in an increasingly nationalistic country. | [
"In the modern era, there are several major loci of the French language, including Standard French (also known as Parisian French), Canadian French (including Quebec French and Acadian French), American French (for instance, Louisiana French), Haitian French, and African French.\n",
"Until the early 20th century,... |
why does white bread crisp quicker compared to brown bread when toasted? | It's made mostly from white bleached flour and is generally lighter in both appearance (so the toasted bits show up better) and density than most brown breads.
The latter are generally coarser and heavier, and have more of the doesn't-burn-so-easily parts of the wheat grain in them like the grain's skin, particularly "whole grain" types of bread or most artisan types that can often be much denser. So it takes longer for them to heat up, reach the burning point of the material that's in them, and lose enough water content on their outside surface to show the charring. | [
"White bread serves as the baseline of 100. In other words, foods scoring higher than 100 are more satisfying than white bread and those under 100 are less satisfying. The satiety score was negatively correlated to the amount eaten by participants at a subsequent buffet.\n",
"Toasted bread slices may contain Benz... |
my bird starts chirping when he hears other birds of completely different species. why? | Birds can only have offspring with their own species, so recognizing your own species is done through the specific songs.
Birds are also quite territorial, not just for nest building but also for general food and water resources in the area, so singing is a great way for advertising that this is your area.
So they're not really talking as much as they're basically saying "hey, I'm a Robin, this is my tree, any single robin ladies in the area?". And then other birds sing their own songs to say they're also here, basically responding "hey, this is my house and I'm not a robin, please leave!" | [
"This species is heard more often than seen, but its calls often help to locate it visually. To vocalize they move higher off the ground than during their usual activities, and may perch on an exposed site. They also nod their head and bow their body when calling, making them even conspicuous sometimes. Calls like ... |
Why did camels never catch on as transport animals in the American West, as they did in almost every other desert/plains on earth? | Interestingly, both camelids and equines are native to North America - after having colonised Eurasia, both vanished from North America, most probably having been hunted to extinction after humans colonised the continent, roughly 8-10 000 years ago.
HORSES:
Horses returned in 1494, with the second expedition of Columbus (to Hispaniola at that time). Later explorers and colonists also took horses. In a very literal sense, they returned home, and lost or escaped animals quickly established a large population of feral horses. This time though they were appreciated by the natives as more than meat, and they quickly became an important part of indigenous culture.
The homecoming of the horses was so successful, in fact, that the US government started exterminating them in an organized manner, since with the decline of large predators, they quickly became pests. It's still a recurring [problem](_URL_2_) actually.
CAMELS:
As for camels, they were also brought to North America, though much later, only when arid lands in the west became a major logistics issue. There have been [attempts](_URL_0_) by the US army to use camels in pack trains, and about 75 animals were imported. The experiment was ultimately a failure for a variety of reasons: The Civil War started and the "experimental camels" were seized by confederate forces, and also the camels were reportedly treated very poorly by drivers who were opposed to using them. After the Civil War, the expanding railroad network delivered the last blow to the camel project. The animals have been sold to various places, from slaughterhouses to zoos. Not all the animals have been accounted for though, and some have clearly wandered off, but probably far too few to start a population. There are rumours of sightings, though :) .
EDIT: To give you a short answer, I think above information indicates that horses and mules dominated the field mostly because they were there first, had a huge population advantage, they were accepted by people of predominantly european heritage, and because the people who built business on them were wary of any kind of competition and replacement.
Sources:
Stephen Budiansky - The Nature of Horses
_URL_1_ | [
"The camels were used as pack animals, especially in the north, while in the south, camels were used to pull drays with supplies for the riders. Camels were ideal for this as they could go for a long time without water, and it has been suggested that the fence could not have been built or maintained without the use... |
how come some vendors require my debit card pin but others do not? | Your debit card has Visa (or another credit card company) backing it. Each transaction can be run as debit (processed by your bank directly, requires your PIN) or credit (processed through Visa, does not require your PIN).
Processing as credit through Visa is to your advantage as the consumer. The consumer protections are much greater. If there is fraud or a dispute, you have a lot more power to get it fixed quickly.
Vendors don't want you to choose this option, because when you do they have to pay Visa a transaction fee. This is why some shady Point of Sale systems will force debit even if you try to pick credit. You could complain to Visa about these places and they would probably be forced to fix it, but ain't nobody got time fo' dat.
When you use debit, the money is literally pulled out of your account immediately without that intermediate "credit stage". This is a big deal, for example if you use it to check in at a hotel then the full amount of the hotel's holding amount will immediately be pulled out of your checking account. Versus the credit card approach where it is just a "pre-authorization" transaction that doesn't actually hit your account until they complete the posting. | [
"Because the customers have to use a PIN code in the BankAxept system, but not with many other systems, it is also much more frequent that stolen debit cards are abused in card fraud with merchants that only have an agreement with the international payment systems and online.\n",
"Chip and PIN systems can cause p... |
why do stores display fruit and vegetables outside where people could steal them? | Other than street urchins and tykes, who is stealing apples from a store front? | [
"In addition to shoplifting, thievery also has been due to pilfering by shipping personnel and burglary. Book stores also are victimized by thefts of merchandise and other items aside from books. At Vroman's Bookstore in Pasadena, California, someone attempted to steal a security camera. At the Boulder Bookshop in ... |
How do we know what is in the center of the Earth? | One way is from looking at p and s waves that travel through the earth when there is an earthquake. Direct observations of things come from looking at light, which is just a wave. So looking at waves that travel through the earth can then be used to probe deeper than our eyes could see. This can give you things like the boundaries (roughly) of where the "stuff" that makes up the Earth changes from one material or state of matter to the next. These waves are basically how we know the radius of the inner and outer core.
& nbsp;
This information can be combined to observations of the Earths orbit to get ideas about the density. Combine this with what the p and s waves tell us about the internal structure and what we know about the properties of various materials and we get some ideas on the composition of the inside of the earth.
& nbsp;
But there is more! From the observations of the magnetic field we can probe deep into the earth based on what we know about magnetic fields. This gives us information on the fluid motions as well as the timescales of the different regimes within the mantle and inner/outer core.
& nbsp;
There are a LOT more other things one can do beyond these things. | [
"The geographical centre of Earth is the geometric centre of all land surfaces on Earth. In a more strict definition, it is the superficial barycenter of the mass distribution produced by treating each continent or island as a region of a thin shell of uniform density and approximating the geoid with a sphere. The ... |
why do i need planning permission to build on land i already own? | So you've got this nice piece of land and you've spent your life saving building yourself the house of your dreams on it, then a company buys the piece of land next door to yours and builds an abattoir on it. This makes your property stink off rotten meat all the time and be constantly swarming with flies, making it practically impossible to live in and causing it's resale value to be utterly worthless.
This is why planning permission is required, so that when permission to build the abattoir is applied for you will be notified and have the opportunity to raise an objection, and possibly stop it from being built. | [
"A development easement is a legal agreement by which a landowner surrenders the right to develop a designated parcel of property. Some local and state governments have programs to acquire development easements from private landowners to prevent conversion of farmland to other uses.\n",
"Planning permission in th... |
how do humans taste things like smoke and metallic flavors if there are only five tastes (salty,sweet, sour, bitter, umami)? | While the tongue only detects 5 ‘tastes’, smell is also a compnent, and it is this that creates ‘flavour’. Without any sense of smell an apple and onion would taste VERY similar. Food is ‘smelt’ through olfactory glands in the nose, via the internal nasal cavity.
EDIT: Corrected location of glands per several commenters below. Thanks guys. | [
"The Minbari sense of taste is not as developed as that of human beings, but they have a more acute sense of hearing. Because of this weak sense of taste, Minbari prefer hot, spicy foods. Minbari do not drink beverages containing alcohol because it affects their systems in a way that causes psychosis and homicidal ... |
how do bagged cereal companies not get sued? | A patent only lasts about 20 years in most cases. So it is perfectly fine to make the exact same product. Thus, it is only the trademark laws that you have to get around. If you can argue that a person wouldn’t confuse your Big Fatty’s sugared broccoli squares with Nestle’s sugared broccoli squares, then you are all good. | [
"The cereal gained popularity for commercials often depicting squirrels stealing the cereal by outsmarting the owners. Among the most popular was Robo-Squirrel, in which a cyborg squirrel does serious damage to steal the cereal.\n",
"On November 22, 1977, Jenner went to San Francisco to refute charges filed by Sa... |
Why didn't Scotland rise against British reign as Ireland did in the modern history? | Because Ireland was effectively ruled as a colony, politically separate from England but completely subordinate to it. The native Irish were treated pretty horrifically - in fact, Theodore Allen in his book *The Invention of the White Race* makes a strong analogy between English racism towards the native Irish and the attitude of white colonists to Native Americans and African slaves in North America. The religious dimension added by the Reformation only made that worse and transformed it into a Protestant-Catholic conflict.
Scotland was never remotely on the same level. Unlike Ireland or Wales (and some would add Cornwall, and even Northern England), it was clearly a partner within Britain, rather than a part subjugated and forcibly controlled by England, like the others. Scotland might clearly have been the *lesser* partner, but it was a partner nonetheless. While after the Jacobite Rebellions, there was a pretty significant suppression of Scottish Gaelic identity to bring it more into line with England, it was never on the same level as Ireland.
And of course, there was no Great Scottish Potato Famine. | [
"Scotland, meanwhile had remained an independent Kingdom. In 1603, that changed when the King of Scotland inherited the Crown of England, and consequently the Crown of Ireland also. The subsequent 17th century was one of political upheaval, religious division and war. English colonialism in Ireland of the 16th cent... |
Whose portrait is depicted in this image from the USSR in 1920? | I've been wondering about this too. I think it might be [Mikhail Frunze](_URL_1_), who was a Red Army Commander during the Civil War.
Edit: Yes, it is Frunze. [Here's the same photo](_URL_0_) with a biography of him on Spartacus. | [
"On the stamps of the USSR, Lenin was most frequently portrayed among the Bolsheviks. After 1923, his pictures were present on about 11% of all Soviet stamps. Lenin portrait first appeared on a stamp series that was the printed immediately after his death in 1924. Images of the first Soviet leader soon became ubiqu... |
Education in ancient Egypt | The ancient Egyptians used two writing systems, hieroglyphics for religious literature and hieratic for everything else (administration, governmental edicts, mathematics, etc.). We know that schools attached to important temples and government departments definitely existed, and were presumably staffed by priests and scribes. Boys of elite families would be sent to school to learn hieratic along with other subjects such as arithmetic. Those who trained as scribes or priests would additionally be taught hieroglyphics. I cannot comment on your third question unfortunately. Hopefully someone more knowledgeable on the subject will chime in.
Source: Warren R. Dawson, *Education in Ancient Egypt*, Science Progress in the Twentieth Century (1919-1933), Vol. 20, No. 77 (JULY 1925), pp. 109-119 | [
"In technology, medicine, and mathematics, ancient Egypt achieved a relatively high standard of productivity and sophistication. Traditional empiricism, as evidenced by the Edwin Smith and Ebers papyri (c. 1600 BC), is first credited to Egypt. The Egyptians created their own alphabet and decimal system.\n",
"The ... |
how do astronauts shave? | Who other than Chris Hadfield to answer the question:
_URL_0_ | [
"BULLET::::- Apollo 10 returned to Earth, after a successful 8-day test of all the components needed for the upcoming first manned Moon landing. The aircraft carrier \"USS Princeton\" was within three miles of the splashdown target in the South Pacific and recovered the capsule. The three astronauts— Cernan, Staffo... |
why do bands keep pretending to end a rock show, but always comeback for an encore to play like 2-3 of their best songs? | it's building hype.
and in many cases they: (one of this options)
1. love the crowd, so they want to give them more
2. pretend to love the crowd, so they want to make them happy. | [
"Since then, Rock@Random does not repeat songs too frequently, and does not play the same songs in the same order. It provides a great variety of rock music that is safe for public places because to the editing of profanity. The range of music is from Iron Maiden to Bob Seger, Judas Priest to Pink Floyd, Nirvana to... |
to me, why can't *japan* just print money | Okay, so, here's what you need to understand: when the government prints money, they are *tricking* everyone into spending more money. People aren't *truly* richer, because there isn't more stuff. There's just more worthless pieces of paper.
The second thing you need to understand is that when the government prints money, the main people they are trying to trick isn't *people* like your mommy and daddy. They're trying to trick companies. Here's how it works: the government prints money and give it to your mommy and daddy. They spend some of it, but they also put some of it in their bank accounts. All the other mommies and daddies put some of the money in their bank accounts too. So after the government prints money and gives it to people, the bank ends up with a whole lot of money.
Now, let's say that you're thinking of opening your own lemonade stand, but you can't afford $100 for a nice big neon sign, which would attract more business. One thing you might decide to do is go to the bank and ask them to borrow $100, and then you promise to pay them back later, plus a little extra for their trouble. That extra is called *interest*.
Before the government printed all the money and gave it to your mommy and daddy, the bank might have said, "well, we don't have very much in our accounts right now, so we'll have to charge you an extra $30 interest". And you might have decided that $30 was too much, and decided not to buy the sign. But *after* the government prints the money and gives it to your mommy and daddy who then put it in the bank, the bank might say "well we just got a whole bunch of extra money in our accounts last week, so we'll only need to charge you an extra $5 interest". And that, you might think, is a great deal, so you take it and buy the sign.
Most businesses buy all their signs by borrowing money from the bank, and the less interest the bank charges, the more signs that businesses will buy [stepping outside of 5 years old here. Signs are a metaphor for all investment spending: building houses and buildings, factories, machinery, expensive computer systems, etc]. And since the government can control how much interest the bank charges by printing money, they can get businesses to buy more signs by printing money. If more people can afford more signs, then they'll start more lemonade stands and other kinds of businesses, and more people will be able to get jobs at those new lemonade stands.
*But*, say you do some research in your neighbourhood and you find out that people aren't feeling very good about how rich they are, and they don't want to spend extra money on things like lemonade. Whenever the government prints money and gives it to them, they decide to put more of it in the bank instead of using it to buy lemonade. Maybe a lot of them don't have jobs too. You realize that your lemonade stand probably isn't going to be very successful, and so you decide not to borrow the $100, even though the bank only wants to charge you $5. In fact, you wouldn't even want to buy the sign if the bank was only going to charge you $0. You decide it's better just not to open a lemonade stand at all, no matter how little the bank will charge you to borrow money.
In that situation, the government is [trapped](_URL_0_). If the government lowers the interest that the bank charges by printing more money, then businesses might want to buy more stuff. But if businesses are so worried that they won't even borrow money for zero interest, then the government can't do anything by printing more money. In that situation, printing more money is kind of like spinning the tires on a car when it's stuck in a ditch. It just digs the car in deeper.
And that's the kind of situation that Japan is in.
| [
"The practice of \"oshigami\" arose due to differences in the sales infrastructure of newspapers between Japan and other countries with large newspaper industries. Japanese print media is primarily funded from the sales of the media itself, rather than the sale of advertisements within the media, as is common in th... |
Tattoo with skin cells gene spliced to glow? | What you're describing is all technically possible. We are able to [transfect human cells to express GFP](_URL_0_), a commonly used marker that fluoresces green under UV light. We are also able to culture skin cells *in vitro* for the purpose of [future engraftment](_URL_1_).
The biggest issues are not what you said, because immune rejection can be overcome by autologous grafting (though there may still be issues with the GFP protein itself), and there are no mechanisms for transplanted epidermal cells to spread elsewhere. Instead, difficulties may arise from safety/efficacy concerns over successfully transfecting epidermal cells to express GFP without altering other key cellular processes. I also don't see much drive for researchers to work on this, because of the limited applicability. There's a lot of work using fluorescent markers in other animals to learn more about embryologic processes and other concepts that require cell tracking/identification, but I haven't heard of much in that field with humans (also because those experiments would be pretty difficult to get IRB approval). | [
"Local allergic responses to many tattoo pigments have been reported, and allergic reactions to tattoo pigment after Q-switched laser treatment are also possible. Rarely, when yellow cadmium sulfide is used to \"brighten\" the red or yellow portion of a tattoo, a photoallergic reaction may occur. The reaction is al... |
the limit of tornado wind speed and why tornadoes might never become ef6 | Tornado and hurricane scales run from "Ehh"(EF0/Tropical storm) to "OH SHIT!"(EF5/Cat 5), in both cases we give the upper category an open upper bound. EF5 tornadoes have wind speeds > 200 MPH, even if you find a 300 MPH tornado, it would still be greater than 200 MPH and fall into the EF5 bucket
An EF5 tornado will demolish pretty much everything it comes across and throw train cars like toys. Even if the wind speed increases, the damage is pretty complete already
There's also the concern of thinning the scale out too much. There are lots of EF0-EF3 tornadoes but significantly fewer EF4 and even fewer EF5s. If you added more granularity then you might see an EF6 once every few years and an EF7 once a decade but those won't be useful classifications. A few, nice large buckets makes categorization much easier for those categorizing and those understanding what it means
If you hear there's an EF5 tornado coming you should think "OH SHIT" rather than "Well, at least its not an EF6 ¯\\\_(ツ)_/¯" | [
"Tornadoes wind speeds generally average between and . They are approximately across and travel a few kilometers before dissipating. Some attain wind speeds in excess of , may stretch more than a across, and maintain contact with the ground for more than .\n",
"Tornadoes' wind speeds generally average between and... |
What kind of fish is this? Caught in the Gulf of Mexico off of the Florida coast. | Looks like a Frogfish/Anglerfish of the genus *Antennarius*. | [
"This species is distributed in the Atlantic Ocean and Gulf of Mexico along the eastern coasts of North America from Maine to Yucatán. It does not occur in the West Indies. It is well known in the Chesapeake Bay, where it is the most abundant fish.\n",
"Its range is along the eastern coast of North America from s... |
a small-case 4-letter password has 456,976 possible combinations. why is there a need for even stronger passwords? | While ~457,000 sounds like just an absolutely unfathomably large number to a human, that's actually child's play when it comes to computers. [Kasperky Labs](_URL_2_) estimates that an average computer that's not even particularly specialized to password cracking can attempt roughly 7100 passwords every second. That means it could figure out a 4-letter single-case password in at most 65 seconds. I'm sure you can see why that's not very desirable.
Even just stepping up to a six-character password where lower case, upper case, and numbers (but no symbols) are allowed slows down an average computer's brute force attack to 3.5 days. This can be sped up by using known tables of common passwords that people use over and over again, or even just using a dictionary attack since most people use a password that's a word or some variant thereof (e.g. they might use "acc1d3nt" instead of "accident," but a good dictionary attack can account for these variants too).
And that's all to say nothing of the fact that people who make their living by cracking people's passwords are going to have specialized hardware that can crack passwords even faster. In 2012, [ArsTechnica](_URL_0_) wrote an article about a then-new supercomputer that could guess up to 350 *billion* passwords every second (meaning the 6-character password from before could be cracked in a fraction of a second). And you can surely imagine that even more powerful hardware exists now, 8 years on.
> Most websites also have a brute-force protection that disables password guessing after about 10 attempts.
This is true, but again people who make their living cracking passwords have ways of circumventing this. Explaining the exact specifics would probably make this explanation not ELI-5 anymore, but the basic gist is that they don't actually crack your password by going to the website and entering each potential password one at a time. Else, as you mentioned, they'd get locked out and that would make the process take a long long time.
Rather, what they usually do is they get their hands on a master password list directly from the source. This can sometimes come from a leaker who works for a particular company, but most often it comes from hackers breaking into to the company's database and getting the master list file that way. Now thankfully, any company worth their salt encrypts said password list, but that turns out not to really be a problem for hackers.
Most of the time hackers know what encryption algorithm a particular website uses to secure their passwords (e.g. the ArsTechnica article mentions that LinkedIn uses the SHA-1 algorithm. Obviously, this may no longer be the case today, but it was true as of 2012). Given this information, they can use their brute force password generator and run each one through the encryption algorithm until they find one that outputs the same string as one of the passwords in the list - they then know that user's password.
In addition to all of that, sometimes companies utterly fail at security and don't follow the industry best practices for securely storing passwords. In late 2013, a password list containing over 153 million Adobe Creative Cloud passwords was leaked. Subsequently, hackers discovered that Adobe did a very bad job securing this file. They used an encryption algorithm that is easily reversible and stored users' hints in the same file as their password. Properly secured password files also use a process known as salting, whereby if two (or more) users have the same passwords, they end up being stored as completely different encrypted strings... but Adobe didn't make use of this, so if the list showed, say, five instances of the same string, hackers just got a 5-for-1 deal on that password.
As a final note, on rare occasions hackers will actually try logging in through the website and brute forcing it that way, if there's an exploit that circumvents the lock out routines. It's believed that such a vulnerability played a role in allowing the leaks of celebrities' nudes from their iCloud accounts back in 2014. [The Next Web](_URL_1_) writes:
> The vulnerability allegedly discovered in the Find My iPhone service appears to have let attackers use this method to guess passwords repeatedly without any sort of lockout or alert to the target. | [
"The full strength associated with using the entire ASCII character set (numerals, mixed case letters and special characters) is only achieved if each possible password is equally likely. This seems to suggest that all passwords must contain characters from each of several character classes, perhaps upper and lower... |
Why is it that you can cut/penetrate things so easily with pointy objects? Why is it that a greatly increased pressure from a needle or knife causes abrasion? | Think of a person laying on a bed of nails. The person's force is fixed, lets say 250lb. However, obviously laying on an entire bed of nails is safe, and laying on a single nail is not.
This comes down to the strength of the molecular bonds of the persons skin. If you apply enough force between two molecules (or cells, or to a crystal lattice, etc), then you'll overcome their bonding force and they will separate. Its like driving an axe into a block of wood. It will split them apart.
When the force is spread out, like a bed of nails, none of the individual nails have enough force to break the persons skin... same with a blunt knife. | [
"A sharp object works by concentrating forces which creates a high pressure due to the very small area of the edge, but high pressures can nick a thin blade or even cause it to roll over into a rounded tube when it is used against hard materials. An irregular material or angled cut is also likely to apply much more... |
why the hippies were so horrible to soldiers returning from vietnam | Viet Nam was the first televised war. Korea, WWII, and even some from The Great War may have had newsreels at the movies, but for the first time you could see Soldiers engaging in an unpopular war.
Showing the war on the 6 o'clock news also meant that the draftees knew exactly what they were getting into. With WWII, a lot of people who went to war thought it was nothing but glory and medals. That was what the newsreels showed.
With Viet Nam, it was a lot of young men dying horribly and being forced to kill people they couldn't even see.
At the time, the young people, the Hippies had learned that they had a choice, and they had a voice. A lot of the Hippies believed that the government of a country several thousand miles away made no difference to the young people here in the US. They thought that because they stood up to "The Man" here in the US and decided they weren't going to go to a war they didn't believe in, no one should.
Relate this to Dancing with the Stars, or the Green Bay Packers. How could anybody see that we are not right. These are the best choices.
Since the Hippies stood up to The Man and refused to show up to the draft board, how could any thinking person. Those that did enlist or were drafted must support the war. If they supported the war, the Hippies felt, they must support everything that is done in the war.
I know I have oversimplified a lot of stuff, but that is the basic 5YO version. | [
"Upon his return to the United States, Rambo discovered that many American civilians hated the soldiers returning from Vietnam, and he claimed that he and other returning soldiers were subject to humiliation and embarrassment by anti-war \"hippies\" who threw garbage at them, called them \"baby killers\", and exclu... |
What where the major advantages/disadvantages of the Roman testudo formation? | While you're waiting, check out these threads for information on the turtle formation:
[Roman testudo in medieval times](_URL_1_) by /u/novashadow1324
[Military historians, can you explain why infantry forming square (or other similar defensive formations such as the Roman "turtle") were effective at protecting infantry against cavalry charges before advent of the machine gun?](_URL_0_) by /u/alt247 | [
"Phalanxes facing the legion were vulnerable to the more flexible Roman \"checkerboard\" deployment, which provided each fighting man a good chunk of personal space to engage in close order fighting. The manipular system also allowed entire Roman sub-units to maneuver more widely, freed from the need to always rema... |
What weapons were used in the Franco-Prussian War? | Both French and German infantrymen were armed with a breech-loading, bolt action rifle utilizing a paper black powder cartridge. The German and French variants (Dreyse "needle gun" and Chassepot model 1866, respectively), were a marked improvement on the muzzle loading rifle-muskets they replaced, and the Franco-Prussian war was the first major conflict in which they were fielded by both sides. The Chassepot was generally considered the superior weapon, but the advantage conferred to the French strategically was negligible. I admit I don't know a great deal about the sidearms of the conflict, although I would conjecture that cavalry troopers were most likely issued some sort of standard revolver. The French had retired the Lefaucheux m1858, a pinfire revolver, five years before the war broke out, and it was never officially issued to the army, although marines, as part of the navy (which did make use of the weapon) may have carried them. In contemporary photographs and illustrations, infantry officers are almost never carrying pistols, suggesting that they weren't issued sidearms at all, while most cavalry and artillery officers have one. Perhaps officers brought a wide variety of pistols as part of their personal effects. I just don't know enough (or have enough time) to give you a definitive answer.
Artillery demonstrated a greater disparity in arms and organization. In 1870 the French were transitioning from the La Hitte artillery system (consisting mostly of rifled muzzle-loading cannon, and designed to retrofit old pieces to fire explosive shells), which had been in place since 1858, to a newer system built around the guns designed by Reffye. Officially, the standard field gun of the French army was the "Canon de campagne de 7 de Reffye modéle 1870," an 85mm breechloading rifled cannon. At the outbreak of hostilities, however, many French units hadn't been issued the new pieces, and had to make do with the old La Hitte models. In practice this meant that the balance of French formations were supported by mostly muzzle-loading, rifled brass 12 pounders. These would have mostly been retrofitted "canon de 12" pieces. The French also deployed the Reyffe "Mitrailleuse," a forerunner of the machine gun, with their artillery batteries. Their intended purpose was to supplement anti-infantry firepower beyond rifle range and, as Reyffe himself said, "compensate the insufficiency of grapeshot" at ranges beyond 1000 yards. The weapon was deployed in accordance with French operational doctrine, which stressed the use of massed rifle fire from prepared positions, and encouraged French officers to rely on their superior infantry firepower by generally assuming the defensive, and using entrenchments or cavalry maneuvers to resist or neutralize enemy artillery fire.
Prussian doctrine, on the other hand, was designed for the offensive, and their artillery arm reflected as much. The German armies' main field gun, the Krupp C64, was a steel, breech-loading 8cm cannon. It had an effective range of about 3.4km, which greatly outdistanced the majority of French tubes (the old retrofitted 12-pounders, for example, could only manage about 1800 yards). German siege artillery, including the famous 1000-pounder Krupp siege guns used to shell Paris into submission. Krupp, by the way, refers to the Krupp family ironworks, then located in Essen, that produced a huge portion of Prussia's military hardware. Krupp anti-balloon guns were also the first purpose-built antiaircraft weapons.
Mortars, as they're employed in modern warfare (i.e. man-portable, deployed in infantry formations) didn't really exist in 1870. Massive siege mortars, on the other hand, were prevalent in both armies.
Edit: Forgot my sources!
"The Franco-Prussian War: The German Conquest of France in 1870-1871." Wawro 2003
"Tactics in the Franco-Prussian War From Opening Shots to the Battle of Sedan" Johnson
I used wikipedia for dates concerning the French artillery systems (since I didn't want to comb through Wawro looking for them) and for the stuff about the Lefaucheux revolver. | [
"The Potzdam Musket was the standard infantry weapon of the Royal Prussian Army (German: \"Königlich Preußische Armee\") from the eighteenth century until the military reforms of the 1840s. Four models were produced—in 1723, 1740, 1809 and 1831.\n",
"Also in 1870, the Bavarian regiment of the Prussian army used a... |
What do non-Islamic historical accounts say about Mohammed? | I quoted pretty much all the contemporary mentions of Muhammad [here](_URL_2_), let me know if you have any questions!
Edit: Sounds like there are a lot of follow-up questions to this, so I might as well link my answers explaining the [success of the Arab Conquests](_URL_3_), [early Christian responses to Islam](_URL_0_) and [how the Arabs conquered Egypt/North Africa](_URL_1_) :) | [
"Holland looks at the earliest evidence for Muhammad, Mecca and Islam in the first century of the Arab Empire, pointing to a lack of evidence in the historical record to support the traditional account. He points out that there is almost no contemporary historical evidence about the life of Muhammad, with no mentio... |
Will a single gold atom have color? 10? At what point do we notice the color? | Color as we experience it in everyday life is mostly caused by the way many atoms are bonded together. For instance, carbon atoms bonded into a graphite pattern are gray while carbon atoms bonded into a diamond lattice are clear. Single atoms don't have color in the traditional, everyday, sense. But a single atom still gives off a characteristic set of colors when excited (its line spectrum). This is the action at work behind the colors given off by gas discharge lamps such as Neon signs. In a gas, the atoms are so spread out that they are effectively free and independent. Therefore, an atom does have a color in a gas-discharge sense. So, we "notice" the color even with a single atom, but it is just a different effect at work. | [
"Blue gold is an alloy of gold and either gallium or indium. Gold–indium contains 46% gold (about 11 karat) and 54% indium, forming an intermetallic compound AuIn. While several sources remark this intermetallic to have \"a clear blue color\", in fact the effect is slight: AuIn has CIE LAB color coordinates of 79, ... |
why my computer lags when only 50% of the cpu is being used | You've got a bottle-neck! It doesn't matter what system you run, just about every single one of them have multiple things going on all at the same time. Most of them are pretty vital, such as checking to see if you have pressed a key on the keyboard to minor ones that check to see if Adobe Acrobat is the latest version or not. Each of these gets it's own little sliver of time. The ones that are entirely based on memory and CPU, such as updating the little clock on the corner are really quick. Others, such as fetching the next section of the game you are playing or grabbing the next few megs of music off of the CD in your computer are relying on spinning media. Just like the name implies, spinning media is anything that relies on a motor to spin one or more disks and moving sensors (heads) to gather the information needed. These are very slow. Even the advanced hardware used in powerful servers are very slow compared to memory.
So anyway, that process gets it's little sliver of processing time and says "fetch me a shrubbery from the hard drive!" And the good little knights (another process) go off to find it. Now there is no hope that those knights can find it during that sliver of time, much less return it, so the process loses that turn while the knights go galloping off. The next sliver comes around and the knights aren't back yet. They found it, but haven't finished pulling it up. So the process loses that sliver too. Several slivers later the process sees the knights waiting for it pay attention to them. Then it can start working on the shrubbery they brought back. But every single one of those slivers between the order to fetch and getting the data back was a waste for that process.
Let's pretend it used 100 slivers for this work. The real numbers would be significantly higher, but 100 slivers is easier to imagine. The command to go get the shrub is 1 sliver, or 1%. Then starting to work on the shrubbery is another 1 sliver, or 1%. The 98 slivers while it sat there twiddling it's thumbs is 98% wasted. Now there are dozens of processes going on at once. So that -98% really pulls the average down. If even a quarter of the running processes get -98% then you system will show a utilization average of about 50% when it reality it is working hard, just waiting on slow media.
SSD's are a huge improvement but they still aren't nearly as fast as memory. And having your music 100% digital is also a huge step in the right direction, but your computer still has to pull if off of the spinning hard disk to let you listen to it. Even the fastest computers in the world right now have something slowing them down. The only way to get 100% utilization, 100% of the time would be to have a computer that is nothing but the fastest memory, CPU and GPU. Then you would become the bottleneck and that's the way it should be.
Edit: Followed some formatting advice. | [
"CPU time and CPU usage have two main uses. The first use is to quantify the overall busyness of the system. When the CPU usage is high, the user may experience lag. Such high CPU usage indicates insufficient processing power. Either the CPU needs to be upgraded, or the user experience reduced, for example, by swit... |
if a straight razor, single blade, is the closest shave we can get, then why do companies keep adding blades? | A multi-blade razor basically compensates for an improper or imperfect shaving technique. The cartridge attempts to force you to use the proper angle for the blades, and the multiple blades take advantage of the pulling effect of the preceding blades to cut the hair even closer to the skin.
In reality, about 3 blades maximizes this pulling effect, but even a particularly sloppy technique might benefit from 4 or 5 blades. I love my 5-bladed razor cartridges. They last forever and give me a super-close shave even when I am half asleep and using a particularly sloppy technique. I never get razor burn and never use after-shave, even though I have ultra-sensitive skin. There is never any feel of scraping or pulling.
Although it will destroy the lubricated strips on the cartridge very quickly, I swish my blades in grain alcohol (95% pure or better), then dry them thoroughly after each use. One five-blade cartridge lasts for 100 - 125 shaves before it no longer shaves like new. I know a couple of guys who store their blades in a non-corrosive oil and say that the blades last even longer. I'm not sure if that's true, as I haven't tested it. | [
"Still others argue that straight razors provide a superior shave through a larger blade and greater control of the blade, including the blade angle. Straight razors cover a much greater area per shaving stroke, because their cutting edge is much longer than any of the multi-blade razors.\n",
"Double-edge razors ... |
If it was so easy to defend, why did the allies 'have to' attack Omaha Beach on D-Day? | All of the beaches had fairly small gaps in between them, but the Omaha landings would serve to link the American landings further north at Utah, with the Anglo-Canadian landings at Juno and Gold, and thus to the other British landing at Sword. If they had NOT landed at Omaha, the gap between Gold, Sword and Juno Beach, and Utah would have been too great. Rather than linking the beaches in the following days and presenting an extended, united front, the Allies could have been met and bottled up in their beaches, at separate locations. The possibility of the Germans delaying or preventing the American and Anglo-Canadians forces from linking up would have been great, and the losses and the length of the campaign would have GREATLY increased. | [
"Merging the American beachheads at Utah and Omaha Beach was a D-Day objective of the amphibious forces but was not achieved because of heavy German resistance at Omaha. Moreover, Allied intelligence believed that three German divisions were massing to drive a wedge between them. Supreme Allied Commander General Dw... |
Body Temperature and why we can stay alive 90 degrees below our body temperature but will die 90 degrees above. | It is much easier to keep heat in with insulation than it is to get rid of excess heat with sweating or other means. | [
"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... |
realistically, what would have to happen before games (especially vr) can match the photo-realism of film cgi? | Think of it this way.
The deadline for rendering 120 minutes of movie is around 2 years.
The deadline for rendering 120 minutes of video game is 120 minutes + 33ms.
Even counting the fact that movies need to be developed, then rendered, that still leaves about 1 year of rendering available for movies.
No matter how good rendering gets, film cgi will be better than vg cgi. The best we can do is to make film cgi so good that the diminishing return effect kicks in and top-notch cgi v real-time cgi, while vastly different in quality, only look slightly worse in real time generation.
And look at the most recent games v the first short that Pixar made in 1985 (30 years difference). A decent cpu can render something about 3x more detailed than that short in real time, while in that time period they were actually rushing the production to meet yearly trade show deadlines for shorts because of the time it took for them to render. | [
"Nevertheless, despite the fluidity of CGI animals and monsters, purely visual effects are often panned, or, at least, not preferred by discerning film viewers. It is extremely difficult to mimic realistic lighting, leading to most CGI creatures and characters looking obviously fake when placed alongside real envir... |
In the densest parts of galaxies, how close can stars get to one another? | Although a pretty rare event, they can [collide](_URL_0_), or in other words, they can get arbitrarily close.
The densest regions are the galactic nuclei as well as the cores of globular clusters, in which you can have thousands of stars per cubic parsec. The core of M 32, a satellite galaxy of the Andromeda galaxy has about 5000 stars per cubic parsec, which equals one star every 2,5 lightdays or every 66 billion kilometers. | [
"Because of their high density, close encounters between stars in an open cluster are common. For a typical cluster with 1,000 stars with a 0.5 parsec half-mass radius, on average a star will have an encounter with another member every 10 million years. The rate is even higher in denser clusters. These encounters c... |
What are some good books about the Ethiopian Revolution, the Ethiopian Civil War, and/or the rule of the Derg and Mengistu in general? | Robert D. Kaplan's "Surrender Or Starve" is not in-depth and the scope is wider than Ethiopia, but is a good start, and Kaplan is always engaging. | [
"The Derg overthrew the Ethiopian Empire and Emperor Haile Selassie in a coup d'état on 12 September 1974, establishing Ethiopia as a Marxist-Leninist communist state with itself as a military junta and provisional government. Various left-wing, ethnic, and anti-communist opposition groups supported by the United S... |
Did segregation laws in the U.S. South "technically" apply to both blacks and whites? | Some discriminatory laws were written in a way that, at least theoretically, applied to both blacks and whites.
Virginia’s anti-miscegenation law forbidding interracial marriage banned marriage between “a white person and a colored person.” Mildred and Richard Loving challenged the law, arguing that it violated the Equal Protection and Due Process clauses of the 14th Amendment. The case eventually made it’s way to the United States Supreme Court. In [Loving v. Virginia] (_URL_1_), Virginia argued the statute was constitutional because it applied equally to both races because it barred both whites and “colored persons” from interracial marriage.
> the State argues that the meaning of the Equal Protection Clause, as illuminated by the statements of the Framers, is only that state penal laws containing an interracial element as part of the definition of the offense must apply equally to whites and Negroes in the sense that members of each race are punished to the same degree. Thus, the State contends that, because its miscegenation statutes punish equally both the white and the Negro participants in an interracial marriage, these statutes, despite their reliance on racial classifications, do not constitute an invidious discrimination based upon race.
The Court wasn't buying what Virginia was selling because, despite the alleged color-blindness of the law, it only barred marriage involving a white person. There was no bar against intermarriage between other races.
> There is patently no legitimate overriding purpose independent of invidious racial discrimination which justifies this classification. The fact that Virginia prohibits only interracial marriages involving white persons demonstrates that the racial classifications must stand on their own justification, as measures designed to maintain White Supremacy. We have consistently denied the constitutionality of measures which restrict the rights of citizens on account of race.
Although the way Virginia wrote the law may seem to be an obvious attempt to get around the 14th Amendment, it had at least one case supporting its position. A 19th century Supreme Court case had accepted Virginia’s “equal application” argument, although for a law about adultery rather than marriage. But the Supreme Court had previously rejected the reasoning of that case and reiterated that it was no longer a valid theory.
> The State finds support for its "equal application" theory in the decision of the Court in Pace v. Alabama, 106 U.S. 583 (1883). In that case, the Court upheld a conviction under an Alabama statute forbidding adultery or fornication between a white person and a Negro which imposed a greater penalty than that of a statute proscribing similar conduct by members of the same race. The Court reasoned that the statute could not be said to discriminate against Negroes because the punishment for each participant in the offense was the same. However, as recently as the 1964 Term, in rejecting the reasoning of that case, we stated "Pace represents a limited view of the Equal Protection Clause which has not withstood analysis in the subsequent decisions of this Court."
Even though the “equal application” theory was shot down, both *Pace v. Alabama* and *Loving v. Virginia* show that at least some discriminatory laws were written in such a way that the states could use the “gee, we’re not discriminating against blacks because the law also punishes whites” argument.
Having rejected the “equal application” argument, the Supreme Court went on to hold that anti-miscegenation laws violate both the Due Process and Equal Protection clauses of the 14th Amendment.
> Marriage is one of the "basic civil rights of man," fundamental to our very existence and survival … To deny this fundamental freedom on so unsupportable a basis as the racial classifications embodied in these statutes, classifications so directly subversive of the principle of equality at the heart of the Fourteenth Amendment, is surely to deprive all the State's citizens of liberty without due process of law. The Fourteenth Amendment requires that the freedom of choice to marry not be restricted by invidious racial discriminations. Under our Constitution, the freedom to marry, or not marry, a person of another race resides with the individual, and cannot be infringed by the State.
Aside from the constitutional issues, the story of the Lovings, their relationship, marriage and court case is a beautiful and heartbreaking story. They are largely forgotten Civil Rights heroes but every June 12 (the anniversary of the decision in *Loving v. Virginia*) people celebrate [Loving Day](_URL_0_). | [
"In 1896, the United States Supreme Court decision \"Plessy v. Ferguson\" upheld the constitutionality of racial segregation under the doctrine of \"separate but equal\". This decision led to the proliferation of Jim Crow laws throughout the United States. These laws mandated or explicitly allowed segregation in vi... |
Does the deep ocean water pressure make water flow more difficult? | Short answer: no.
Longer answer: currents are driven by pressure *gradients*, amongst other things such as gravity. On short time and space scales, water tends to flow horizontally from regions of high pressure towards regions of low pressure. In the deep ocean high pressures can be caused either by changes in the sea surface height (there is more water over one region than another), or by changes in the overlying stratification (there is more denser water in one region than another).
Fish that live in the deep ocean are equilibriated with the high pressures, which means that the pressure inside their bodies is the same as that outside. They don't "feel" the high pressure as we would if we descended from the surface (where we are equilibriated with atmospheric pressure) to depth.
You may be wondering why water doesn't flow "upwards" from the deep, high pressure ocean bottom to the relatively lower pressure surface. In the vertical direction water is largely in hydrostatic balance, meaning that the vertical pressure gradients are balanced by gravity, so there is no net force on the water (and hence no accelerations and no currents).
Fun fact - over large scales in the ocean water doesn't flow from high to low pressures anymore, instead it tends to follow isobars (lines of constant pressure) due to the fact that the earth is rotating. | [
"The bulk modulus of water is about 2.2 GPa. The low compressibility of non-gases, and of water in particular, leads to their often being assumed as incompressible. The low compressibility of water means that even in the deep oceans at 4 km depth, where pressures are 40 MPa, there is only a 1.8% decrease in volume.... |
car motor oils. | If you run a finger through water and then run your finger through honey, do you feel the difference in how thick the two different liquids are? That thickness is called viscosity, and it applies to all liquids. When you're using an oil, it's important to match its viscosity (when dealing with oil, this is also referred to as "weight") to how you're using it. Too thick and it won't get into all of the small nooks and crannies, but too thin and it'll get out too quickly and won't provide enough lubrication.
With motor oils, it's important to remember that many cars will start cold and then run at a different temperature, and the viscosity of a liquid will change as the temperature changes. So it's 70 degrees outside and you start your car, the motor oil will be very thick compared to after your car has been running for 15 minutes and the engine is around 200 degrees. But since it is important that the car be lubricated when it's cold as well as when it's hot, it's important to know how those oils will behave when heated.
The numbers you see represent the cold and hot weights (viscosity) of the oil. The thicker an oil is, the higher a number, so you need a number that is small for when the engine is cold and a number that is large for when the engine is hot. This is why when you change your oil in the spring they'll put in 10w-40, but when you change it again in the fall you get 5w-30 - the shift in temperature around you calls for thicker oil in the summer so it doesn't thin out too much with the extra heat, and thinner oil in the winter so it can quickly lubricate your engine when you start your car. Your manufacturer has done a lot of testing with the engine to determine which oil weight is ideal for it and will list this information in your manual. | [
"Motor oil, engine oil, or engine lubricant is any of various substances comprising base oils enhanced with additives, particularly antiwear additive plus detergents, dispersants and, for multi-grade oils viscosity index improvers. Motor oil is used for lubrication of internal combustion engines. The main function ... |
What were the thoughts about static build up and shock to people in the past, and was it seen as a sort of witchcraft if everyone has done it at least a dozen times? | There is an excellent older answer to this question by u/hillsonghoods [here](_URL_0_). Just because people in the past didn't have our scientific understanding of the phenomenon, doesn't mean that they didn't have a secular theory of what supposedly caused it. The precursor to modern science isn't witchcraft and superstition, it's just earlier forms of observing and understanding the world. | [
"In the Netherlands in 1746 Pieter van Musschenbroek's lab assistant, Andreas Cuneus, received an extreme shock while working with a leyden jar, the first recorded injury from man-made electricity. By the mid-19th century high-voltage electrical systems came into use to power arc lighting for theatrical stage light... |
how did big army get fed in the past like durring big conquest like crusade | A few ways.
Requisitioning. For an army on their own territory, they will have legal authority to demand supplies, food, shelter, etc. from any nearby residents. This can be extremely difficult for the peasants and some even starve to death. If they refuse bad things can happen.
Pillaging. Invading armies basically do the same thing as requisitioning... but without legal authority. They come in with their weapons and steal everything. Often they also rape and kill everyone, burn down the structures, etc. If the town leader is *real lucky* perhaps he can just give them everything they have and be left alone.
Foraging. Armies have to travel great distances and may not be near towns, or nearby towns don't have enough to feed the whole army. The army will send out teams to collect fruit and hunt animals, and then they cook it at camp.
All in all, peasant life sucked ass. | [
"Prior to the Thirty Years' War, the laws of the Holy Roman Empire provided for funding armies by raising special war taxes. The funds needed for the large armies raised during the war however exceeded the income of the respective warlords from those taxes, and forced them to resort to additional, unfavourable meas... |
if republicans control both houses of congress, why was it so hard to get a homeland security bill passed? | The Republican Party is not united. The establishment faction and the Tea Party faction disagreed over the bill. The establishment faction wanted to pass it. The Tea Party wanted to use the bill as leverage against Obama in order to force him to take back his executive orders on immigration. | [
"The Republican House had narrowly passed a bill on December 20, 2012, which would have replaced only the defense side of the sequester with cuts to programs including food stamps, Dodd-Frank and the Patient Protection and Affordable Care Act. In February with their reduced majority, key Republicans admitted that t... |
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