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175yis | Why don't birds get cold in the wind? | Birds have insulating feathers called *down*. They trap air close to the body so convection (moving air currents) can't pull heat away. To get their feathers to do this, their muscles can make the feathers stand on end -- these are *literally* goose bumps.
By the time it gets warm, they have shed many of their insulating feathers due to molting, and what remains is kept tight against the skin, allowing for maximum cooling. | de2f8af6-2085-45f5-a603-28c289996017 |
5jxgkh | How do airlines make a profit? | The short answer is that the airlines are _exceptionally_ good at price discrimination.
The longer answer is that not everyone pays the same price for the tickets they have. This is very obvious when you think about business class vs. coach - the business class tickes are often > $1,000 a seat for domestic flights and can be > $10,000 for overseas flights.
However, there is significant difference in the prices of coach seats too. I fly for work every week and I promise that I pay _much_ more for my tickets than you ever had. I tend to book them closer to the departure date, I tend to select very specific flights with very specific times and destinations. Moreover, I am much less price sensitive because I'm not paying for the flight directly (my company is) and they are prepared to pay a bit more to have me where I need to be when I need to be there (as opposed to 6 hours later when a cheaper flight might be available). The airlines know all of these things about me (and other similar travelers) so they adjust prices for us accordingly.
When a leisure traveler books a ticket, many of these things change - you book further in advance and you care less about specific flight times; all you care about is price. | 227591fd-0f43-4c75-b4c3-a88fa47b5784 |
4wt7ek | How do Human Beings "absorb" energy from an impact? | There are a lot of sources for energy to go here. Most of it probably ended up being converted to heat eventually. Here's a runthrough of what might have happened:
* The child-bike system has some amount of kinetic energy and is heading toward you
* The bike collides with you, skidding off to the side. The energy of the bike is largely dissipated through friction with the ground, with a bit of the energy going into sound and the energy required to chip or bend parts of the bike.
* The child collides with you. This temporarily deforms your body like [this poor guy taking a football to the face](_URL_0_). Initially, the pressure of the child hitting you would locally heat up your body, though it would quickly cool with decompression. The child hitting you will excite "vibrational modes" in your body, just like hitting a piano string will make noise. These will gradually dissipate due to internal resistance of your body, becoming heat.
* You and the child are sent flying due to the impact. You come to a stop after sliding across the ground. Your initial energy went into
* Removing bits of your skin
* Heating the pavement through friction
* Making a bit of noise
* Further "impact energy" due to any large objects you might have hit in turn
It's hard to say where exactly the energy will go in what proportions for a complex system like this, but it's generally a good guess to think that the vast majority will end up as heat. Try dropping a bowling ball on the floor a few times. You'll notice it will get quite hot. | edf9fbb3-723b-43e5-ad86-919d1e325620 |
4l33rf | Why is it sometimes taboo to classify transgender folk as having a mental illness? | Because one criterion for mental illness is that the behaviours and thoughts the person is experiencing keeps them from being able to fully function day-to-day. For example, anxiety disorders and depression can impact a person's ability to go to school, to work, to hold social ties, etc. Feeling like one's gender is not strictly male or female is not an illness. It is an expression of the self, just like whether someone is neurotic or secure, introverted or extraverted, etc. Mental illness has to do with the impact on the person, just like any other illness; it is not because other people feel uncomfortable. | a056c337-e0c8-4284-b861-ba9073438486 |
6449vt | why can you still feel the ebb and flow of the waves when lying in bed after swimming in the waves during the day? | Your body seeks equilibrium. It is always trying to balance your senses out so that you can tune out normal things, and be alerted to anything in your environment that is different. For example you put an air filter in your bedroom and the first few days you are very aware of the fan noise. After a few weeks your wife turns the air filter off in the middle of the night, and you suddenly wake up because something has changed, it's gone quiet. Your mind learns to filter out the sound of the fan because it's gotten used to it.
The same thing happens with smells. You put a candle in your room and you smell it really strong, but after a few weeks you don't smell it at all. Then you go on vacation for a week and come back, and you can smell it again. It's one of those reasons why you don't really smell your own home until you've been away from it awhile.
When you drive in a car, your body gets used to the forces placed on it as you go over bumps and around corners and your mind eventually tunes it out. Your body is also used to not moving around when you get out of the car, so it doesn't feel weird when you're not driving the car. If you get used to driving at a certain speed, your mind and perception of motion will compensate as well, and then if you drive slower, it seems really slow. Doing 70MPH for several hours on a road trip makes going 40mph inside city limits feel like you are crawling because you got used to 70mph.
However, when you go swimming, your body is bobbing and floating around the water, and your mind is trying to get used to this sensation and filter out the motion. Then later when you are still, your body is still getting used to being still again. If you were to go swimming every day, eventually your body would get used to the transition from water, to land, to bed, and you wouldn't notice feeling waves in your sleep anymore the same way you don't feel weird driving in a car, then sitting in a chair at work. But when you were a child, you probably got a little carsick at times, or got dizzy when getting out of the car. But it was so long ago you forget about it. If you spend a lot of time on a boat and get used to the rocking, it can feel strange to step on dry land again because your body and mind were so used to compensating, they cant suddenly stop doing it, so you have a little trouble walking straight. | e41d5044-0586-426d-8b95-686a72a57221 |
7okdlm | Why does a vehicle 15 mph faster than you appear to gain a much greater distance from you depending on your own speed? | Because when sitting still, you have all of your environment in the same relation to the moving car as you.
However when you are moving 70mph, the only reference point you have is your car and the other car to judge the speed difference. | 4e557b1c-6507-4d50-a23f-380cffc2bef3 |
6bfoc9 | Why do we experience a 'burning' sensation in our eyes if we haven't slept for a while or immediately after waking up? | It might be that "crusty" discharge from your eyes called rheum ( a mixture of different kinds of cells, mucus, dust, etc.) that is released during sleep. It looks likes sand in your eyes hence the saying.
The burning from sleep deprivation is just like what sleeplessness does to the rest of the body, give it fatigue. | f391a0f0-fb17-42b7-900b-0aa316bff3df |
1vwcl5 | When someone sues another person who's not financially well-off for a huge sum of money, how do they get paid? | Essentially she won't. She can attempt to take money from wherever he may have some, and then on top of that try to take a percentage of any earned (garnishment). But the reality is she won't get a dime. | cc53e781-c68b-4a26-b381-55a0d52a8a27 |
4vjcz9 | If we can only see the "observable" universe, how can we make conjectures about things like its beginning? | What they mean is that eventually space will be expanding fast enough that all the light will be redshifted out of detectable range.
The universe isnt expanding because of the motion of the galaxies. Space itself is expanding. Every second there is more space between us and distant galaxies.
Our relative spatial velocities could be toward each other but space is expanding faster so we move away from each other.
This expansion is proportional to the amount of space so like compound interest the acceleration due to space time expansion increases. Eventually we will be alone in thw universe.
Now this all assumes that expansion is universal and non reversible.
At some point in the future we could have the reverse happening.
Im not sure what physics says about that. | 209eae63-1215-4270-b8fa-509a3c2785ae |
4x1myj | How do people on drugs, such as meth, supposedly get superhuman strength, taking multiple people to subdue them etc? | People are generally stronger than we think. We have built-in safety margins, like the warning line in a pressure valve, so that we don't accidentally injure ourselves... these safety margins are often very cautious, preventing us from exerting anything like our full possible force (except for in emergencies, where things like adrenaline shut down some of the safety mechanisms).
Some drugs either directly shut down the mechanisms (by triggering or emulating surges of the relevant hormones), or otherwise prevent us from being aware of them.
A big part of these mechanisms is pain responses. Drugs often significantly mute pain.
So, you have a person who is unaware of pain and is being as frantically strong as people can be in a severe panicked emergency, versus people who are still very aware of their own pain and perceived limits (and who are often trying to not severely injure the target).
So, it's not that the person has _extra_ strength from somewhere, it's that a person who has had all the limits taken off, against people who are still severely limited in multiple ways, _appears_ superhuman. | 2db41de4-45d0-4af2-b74b-0a1fe887d580 |
4cixvb | If fusion reactors fuse hydrogen into helium, wouldn't we run out of hydrogen at some point? | Hydrogen is the most abundant substance in the universe. 90% of all the atoms that exist are hydrogen. There is so much hydrogen locked up in fossil fuels that we could just use them for millennia before we even started using water, or sending spaceships to collect it. | 7895efd9-51e2-4159-93a9-db10ed4e3679 |
4ie85v | Why do we have the capacity to hate ourselves? | Free thought and free will has many positives and negatives. Increased intelligence means that we also can see the uglier sides of things, and well.... | 5bf08ee2-0464-433f-a511-ba101fc1cf84 |
3791oq | What is the "shy bladder" and what can people do to get over it? | > What's going on
You're having an expectation that someone may intrude on your urination, which in turn makes you unable to relax.
> how can I make it easier on myself
Find someone to squeeze you. /meta
You may need to somehow snuff out all surrounding sounds to help you unwind and start peeing. | fe7860d0-78ec-499e-8959-3786b1797108 |
2bhon2 | - why do most honour killings involve murdering the victim? Why not kill the rapist instead? | In such cultures women are viewed as property, to be bought, sold, or traded. The honor killing is in retribution for the perceived dishonor of allowing themselves to be raped, as it damages or destroys their value to their male owner.
It is fucked up. | eeba2502-cef0-4e84-acba-33b247b3cb8c |
58o51w | Who writes the stuff that goes in fortune cookies? | Apparently, the [CFO of the company who manufactures the fortune cookies](_URL_0_). Maybe that's why they so often refer to wealth? | c258223a-9674-47d3-ab35-dc3e9e4dff53 |
30lfwe | Why is it that if you exhale like blowing out a candle the air is much cooler than if you exhale like you're checking your breath? | Hi, Mechanical Engineer here. I assume that when you blow out a candle, you purse your lips. Air is pushed out of the small hole and this creates a high pressure, fixed volume chamber in your mouth and exits to a lower pressure, free volume atmosphere. This sudden change in pressure causes the volume of air contained to expand and the temperature to drop, making the air you blow feel cold. This is also known as [Adiabatic Cooling](_URL_0_)
On the other hand, when you check your breath, your mouth is open wide enough that the pressure between the inside of your mouth and the air is similar to one another and the volume is no longer contained. The warm air is now caused by your body temperature heating the air as it leaves your body. | 44f199a2-5d34-4acf-9861-16e039a409d9 |
33ie1n | What is the significance of a full metal jacket in small arms ammo? | Bullets were originally just cast lead, and many people still do cast bullets this way (I used to). This can lead to lead deposits in the barrel which will hurt accuracy as well as a bunch of lead in the air (not a good thing). The FMJ is a copper jacket around this soft lead to make it more stable in flight as well as not leading the barrel. On top of that, lead is some soft and can lead to bullets getting deformed rather easily; FMJs are highly resistant to this. | c95aba6f-85de-4151-ab7f-0817c0ca3001 |
3ea31b | Why and how is it that the Windows operating system hasnt been replaced? | One of the main reasons is that Microsoft makes deals with hardware manufacturers to include their OS in those products by default. This starts the cycle that makes most consumers use Windows regardless of if they're at work or at home. Consumers generally don't like change, so then Windows usage seeps into other areas simply because people are familiar with using it in another context.
OSX is out simply because it's tied to Apple hardware and its licenses prohibits OSX from being installed on non-Apple hardware (hackintoshes are excluded). Much like the iOS and Android comparison; there are more manufactures out there than Apple, so by default Apple is going become niche.
This leaves linux and/or other *nix OSes out there. Because Linux is an open source project and not driven by money there's much less incentive than MS to get consumers using the software. | cfaf24b1-661f-4116-b3c9-4d79a0a907cd |
6g5xcy | Negative electricity prices. | Well, think about it. Suppose someone occasionally offers you $10 if you can somehow use one megawatt of electricity for an hour. Would you accept? It's a great deal, but can you actually do it? It turns out it's not so easy.
You could do it, if you had a couple hundred home water heaters, or a couple thousand (edit: make that twenty thousand) incandescent light bulbs. But those would be expensive to buy, and, most of the time, they'd sit idle. It might not be worth the investment.
You could find a better use, so you'd get something out of the electricity in addition to the negative price. You could use the electricity to produce aluminum, for example. Or you could store it in batteries or in some other system to sell it back later when the price is positive. But it would take you a long time to build an aluminum factory or a giant electricity storage system, so if you were offered this deal today, you'd have to say "no, not yet. Maybe in a few years."
This is why prices go negative: because, during peak production, we now produce so much energy that people can't really figure out how to use it all.
You might also ask why the power generators don't shut down when they have to pay to produce energy. That's more complicated. First of all, not all types of generators are able to shut down and start up rapidly. It costs them more to shut down and start up again than it would to just ride out the negative prices (which only last a short time). Second, the wholesale electricity market isn't the only way generators get paid. Some of them have long-term contracts or get government subsidies that provide additional revenue, so they end up making positive money overall. | e3b324e4-62a8-41aa-b37b-b23bf5e6e0f7 |
4hno7r | Why is St. Louis not as important in the United States as it once was? Is it likely to continue shrinking? | It was very important when the Mississippi was a big hub for transferring industrial products out of the Midwest. The small arms factory my grandmother worked at during WWII in Davenport, IA shipped through St. Louis, for example.
As Midwestern industry declined, so did the shipping of those products out along the Mississippi.
That said, the shrinking of St. Louis is exacerbated in the statistics. While other cities expanded their borders as their populations sprawled, St. Louis couldn't because it was not part of any of the neighboring counties. Chicago, today, makes up something like 80% of Cook County. St. Louis couldn't expand in a similar way because it couldn't take land from a county it didn't belong to. | 0175f053-c48e-4719-876f-09ae4c6532c6 |
2mf11f | How can a computer be infected with virus/malware/etc. by visiting a website? | When visiting a web page, what you're really doing is making a request to a web server to transfer files to your computer. If one of those files contains a malicious payload, and your computer executes the malicious code without being interrupted by antivirus software, it will become infected.
Malicious code is usually introduced through plugins and scripts that run locally on your machine (referred to as client-side scripts). Java, JavaScript, and Flash are the most common culprits. | 66c15c29-cfa4-4736-9a4b-84e8144a6a0d |
1ccklx | why can't people inhale when they get the wind knocked out of them | You know when you hit your leg on something (like you bring your thigh up into a bar underneath the table) and you pause whilst cursing the pain because your leg kind of seems to go numb for a second? That's your body very temporarily immobilising the area to make sure nothing is SERIOUSLY wrong with the part of your body that got hit. The same thing happens with your diaphragm (the chest muscle that pulls down to make your lungs expand) when you get hit in the torso. A second or two of no diaphragm contraction means a second or two of no inhalation. | 83c16c9f-86ee-401f-bb4b-b7a303502cef |
39mpah | What has happened to the babysitting market in the last ten years? | The market is flooded. You have a lot of people who can't get jobs elsewhere because the economy isn't as strong, so there are many people able to work as babysitters. Which not only means that you have babysitters lowering their rates to remain competitive with everyone else, but also advertising whatever benefits they have to try and get that babysitting gig. | 8ec77355-3358-4d7a-9f56-4d813f16788e |
2gopit | When listening to earphones/headphones, why does my music feel louder after I yawn? | Your ears are usually pressurized, which serves as a slight volume reduction in some cases. Over time, the pressure in your ears can accumulate. When you yawn, the muscles used relieve the pressure within your ears, "popping" them and removing the pressure, which allows you to hear better. | 1f1ca080-8ffa-4f75-ad20-d652c06f79f7 |
5qcrux | What does sunlight consist of, and why do some parts pass through windows while other parts don't? | Sunlight and heat are (in simple terms, heat is complex) both electromagnetic radiation. They just have different frequencies (the rate at which the wave repeats itself, think of it like the number of waves in a given stretch of ocean).
UV light (higher frequency) causes sun burn. It’s blocked by special glazing on the glass. Visible light, and IR radiation (lower frequency) which feels like heat, are transmitted through the glass to your body. | 5b378142-3f8a-46e6-92da-96fad3c98457 |
1wbbim | Differences and Similarities Between Computer Science and Computer Engineering. | In Computer Science you will learn mostly programming and a bit of computer hardware and electrical engineering.
In Computer Engineering you will learn computer hardware, electrical engineering, and programming about equally.
Neither is particularly useful for IT which I've always felt was more a skill you learn as you go, not in college. There are trade schools specifically for it though. | f58f7535-5914-4d74-991d-04ef5fb43dbf |
4xttja | Why is it common practice to separate high voltage (120V) wiring/cabling from low voltage (24V) wiring/cabling? | Electrical Controls Engineer here. Basically it is to reduce noise and to not induce voltage into the lower voltage wires.
With ac circuits the currents alternates through the wire generating a magnetic field. Any wire close to this can potentially interact with that field and a voltage will be created in the wire.
The higher the voltage the greater the potential for a low voltage wire like 24dc or especially 4-20mA runs to have noise induced on them. | 8682aa2d-27a6-47d0-8aff-373207ea2c95 |
820rbo | How do smart phones dissipate the heat created by the processor? | I think some of the answers are great, but missing a major point that I want to add:
The chips in smartphones ([SoCs](_URL_0_)) are built from the ground up to turn the energy in the battery into useful work as efficiently as possible.
In industry terms, smartphone SoCs have truly insane Performance Per Watt, which is a unit of how much screen brightness, CPU speed, etc can be achieved using only a joule of energy every second. So to answer the question, mainly because they barely produce any heat. Heat is what happens when energy from the battery is lost, and not turned into useful work.
This is why the mobile device revolution only happened recently. Chips this efficient are a very new invention. | 0edf16b5-02c8-4147-94f3-59667124c2f5 |
59qc6j | Why can we (USA) claim a no flight zone in a foreign country? | Because we have big guns and fighter jets. All we need is a UN Security Council resolution to be able to do whatever we want where ever we want.
In this case, Russia will veto any resolution like that. | da4ad33d-d2d8-4820-af16-1e787bbf520f |
4huj43 | X-box 360 downloadables, the entire Banjo-kazooie game is 48mbs (with heaps of animated scene vids) and a short Banjo trailer is 98mbs to download, why? | The animated cut scenes in the game are rendered in the game - so instead of having a recording of a video for each scene, they just have to include instructions for how the character will move.
Think of it as shipping blueprints for a house (knowing the receiver has the supplies) versus shipping an entire house. | 8971820a-2d08-4427-8326-31a0e61b1591 |
2ue6xr | Why do I get silly or weird when I'm really tired or otherwise sleep deprived? | I've actually read that being sleep deprived is like being drunk. "After 17-19 hours without sleep, performance on some tests was equivalent or worse than that at a blood alcohol content of 0.05%"
Here is the link _URL_0_ | f8a48d85-0f07-43d4-b672-2b93c6721840 |
1ryuph | What is the biological explanation of when your "heart skips a beat", as in when you get scared or nervous? | The feeling you get when you're nervous/scared is due to a rapid increase in your heart rate. Epinephrine (adrenalin) is released, and causes the Sinus node (the main pacing area of your heart) to increase it's rate of firing.
You perceive your heart skipping a beat, but it's actually just beating faster. When hearts actually drop or "skip" a beat, you wouldn't feel anything and would most likely feel a very "weird" or odd feeling (it's hard to explain, that's just what patients have told me).
You can have an extra beat in a normal rhythm, which can be caused by a lot of factors. Usually it's some type of heart pathology though and not due to the normal fight or flight response. | 1b3e61c8-1564-4a0f-a553-e9d4381d4f77 |
2wvbox | Why Do We Still Shutdown Financial Systems for Weekends | 5-day weeks are something that just a few decades ago was the norm. Most towns would essentially be closed on the weekend, especially Sunday (except for the local diner and hospital, maybe the gas station).
It's only relatively recently that 24 hour/7 day businesses have emerged, mostly out of need. They need to be open 7 days a week to be profitable. Some banks and services have moved that direction (TD Bank for instance), but most have stayed put.
Financial services have never had the need. In addition, because the other financial services they interact with to conduct business are also closed, it's basically impossible to be open on those "off days" since you can't get any work done. | f8d97896-f35d-4935-981f-ce7b08a94ee2 |
2bm373 | Why did analogue TV tuners click from channel to channel while analogue radio tuners slid along a scale? | The number of TV channels available in a given area was relatively small, but they were often spread over a very large bandwidth. It was not technically possible to provide continuous tuning over such a wide band, and in any case the mostly empty band space would have provided a frustrating experience.
The answer was the "turret tuner" which rotated a complete new set of tuned circuits into the RF end of the tuner at each click. The tuned circuits were on individual wafers which snapped into the tuner "turret", and an appropriate, pre-tuned set were provided for each area.
By contrast, the fractional bandwidth of the AM radio channels was small, 550 kHz to 1750 kHz, or a 3.2:1 ratio, and many channels were full, particularly after dark, so continuous tuning was technically feasible, and made sense to the consumer. Even then, some early radios provided several pre-settable channels selected by buttons: this was done by mechanically shifting the tuning knob as the button was pressed.
For FM the situation is even better: 88-108MHz, or a ratio of less than 1.3:1. A continuous tuning mechanism is simple, reliable, and cheap to make. | 9135b262-3b0c-4b94-af07-6587e3500b21 |
53nul9 | How is gps for self-driving cars accurate enough when my google gps totally craps out any time I'm in a mall plaza? | Self-driving cars use more than just GPS to navigate; they also use onboard cameras to identify the road, other vehicles, pedestrians, traffic lights, and other potentially relevant information. If they lose GPS signal, they continue going along what was the plotted route until the signal is regained.
As the technology improves, they can also gather data on *where* GPS is likely to fail (such as a tunnel or mall plaza). In these instances, their navigation can plot more detailed courses in advance since the computer is anticipating a loss of satellite feed for a bit. | e406c6ef-e815-4a4a-86d0-78245a81fbe0 |
3x9ick | Why is much more in taxes taken out of holiday bonuses? | So when your taxes get calculated, it's from a tax table. There are different tax tables based on pay frequency. So, if you are paid every two weeks, your employer consults the table for your pay amount, and the amount listed is what they have to withhold -- which is based on 26 times that pay amount. That works out pretty well...
...until it comes to bonuses. See, they have to do exactly the same thing with the bonuses, but what happens is that since the check is more than usual, the tables estimate your taxes at a higher tax bracket.
In any event, you'll get that money back when you file your taxes next year. | 42874605-b57e-4802-b8ad-ab2fa4f11a41 |
p5mhz | Why is this winter so warm (in the US at least)? | Because of La Nina. A current in the pacific ocean is cooler than normal, and that affects weather across North America. | ba2d1b58-d5ce-4f94-a5a8-e7d69b8821bc |
rpkgn | Why the tallest skyscrapers are built only in Asia or North America but not in Europe? | The sky is significantly lower in Europe; there's really not enough height to build such huge skyscrapers. | 85a1a3e9-73d3-4fe8-b28b-13f757de5a67 |
1tq100 | Why does David Cameron want mandatory porn filters for UK internet users? | Information control. Australia's government tried to same thing a couple of years ago but it failed. Turned out that porn was just going to be the first step and then after that it was going to be everything the government didn't like. Whoever controls the information has the power. The idea is to get their foot in the door by saying it's about porn, specifically child porn (which it won't do anything to stop since you don't just find that with random searches) and then after that you just quietly expand it to cover everything else. | 58bc2322-5e95-4033-a76a-2530d351a577 |
4fpq3f | Can anyone explain to me why it's called a traphouse. I know what a traphouse is, I just want to know the origin of the word. | Trap is slang for a place where drug dealers sell drugs. It could be a street corner, alley, or trap house. | b0d59776-fbf6-4197-9ce4-96516d4d6264 |
937ar9 | What are MLM scams and what are examples of them? | The hallmark of a Multi-Level Marketing scam is that the emphasis and reward are heavily weighted against recruitment instead of the actual work of selling a product.
If I hire you to sell vacuum cleaners door to door, and pay you based on your time/amount of sales, then it's a legit job. If instead I pay you relatively little for selling vacuums, but pay you very well for recruiting other sellers, then it's an MLM. | be69ac91-643d-4f1a-b7e6-5c81f01db027 |
39y96o | how are license plates numbers distributed? | Not sure if it's the same in Canada, but states in the U.S. print a bunch sequentially and send them to each local DMV. I'm not sure if they're assigned to an area DMV, or just whichever boxes get loaded. Either way, a specific area will tend to get a whole lot of certain sequences, and not many of others, and the state in general will have more too, since if they print a thousand starting with BNZR[-xxx], there's going to be a thousand more BNZR's than BNZS's, and ~~260,000~~ 676,000 (?) more BN's than BO's. | 7b4a5b9a-f595-499b-b2b6-443461b0a4d5 |
1z1etm | Why do PC's become slow and "aggravating" to use after little time, but Macs seem to stay at top performace for a long time? | IT professional here: Can you please define "slow"? This word is thrown around often when it comes to computer complaints but details matter. Is it taking a long time to boot up? Is netflix choppy? Is it slow when you open a third powerpoint deck? Those can help me answer you better.
The shorter answer is RAM, that helps keep things quick. Additionally, macs I have found are less inclined to have background processes initiated and installed silently. When you hit ctrl-alt-Dlt and go to task manager, then to the "processes tab" that shows you all of those things your computer is doing that you can't see. That list may be longer and thus taking up more of the computer's resources than it is on a mac. | 806395b8-81e2-4e06-8f97-62532b7b7d60 |
23pq44 | Why do browsers and websites prompt you for saving your passwords if it is considered unsafe? | The Average Joe is unlikely to be "hacked", but very likely to forget the password to a site he hasn't used in a while. Browser password-saving is meant to be a convenience feature, not a security feature. | 337e3eed-b59b-42b8-922e-24d869a04414 |
36eb6e | Why does AM talk radio have such a disproportionately large amount of commercials compared to FM music stations? | Your FM station has sneaky ways of putting in advertising even though it might claim to have 55 minutes of music. It's advertising when the DJ comes on between songs and reminds you that they will be at a certain business (AD!) tomorrow from 4 to 6 and they'll be giving away a certain item (AD!). It's advertising when in between songs, the DJ comes on and casually reminds you that the artist they are about to play has a concert coming up (AD!) in a couple weeks and reminds you tickets are still available at a certain website (AD!). I could go on, but I'm sure you get the idea. | 0a2737dd-2ca6-4124-bc3e-27c52824f29a |
3eajuf | What is the overall goal/point of google deep dream? | Google deep dream was developed as a test of Google's image recognition software. Basically, they're running it backwards - rather than taking a picture of a dog, and asking the software "Is that a dog"; they take a random picture and ask the software "show me what looks like a dog". By seeing what the software draws, you can determine what characteristics it uses to determine a dog.
For instance, back in the early days of image recognition, the department of defense thought they'd trained a computer to recognize tanks in pictures. It turned out they'd actually trained the tank to recognize sunny days, because the tank pictures were all taken on a sunny day, and the no-tank pictures on a cloudy day. Google deep dream, for instance, discovered the Google Image recognition thinks dumbbells have a human arm attached to them.
Then they released it to the public because it makes cool pictures. | 07527133-1984-4ccf-81b3-fd7c2ddbf738 |
442y8x | Why does it seem like most funerals in the US are open-casket? | Films and TV do open-casket because of course it is more dramatic and visually interesting.
In the US, the family picks which they want. | 58848707-487d-4d0f-97df-3ae498c73f7a |
69t2nw | Why are we mean to people we crush on or love? | *I hate and I love. Why I do this, perhaps you ask?*
*I do not know, but I feel it happening and I am tortured*
The *tsundere* dilemma has always been with us. It happens for many reasons. Sometimes because the person who feels the attraction is unable, or does not understand how, to express these strange and puzzling emotions. Like when a young boy throws a rock at a girl he likes in the playground and runs off because he doesn't have any other way show how he feels. Everyone knows how to throw a rock though.
Really the most common reason is that we contain multitudes. Falling in love is a huge and dangerous commitment. It runs counter to some of our basic instincts which are based on self preservation. After you are completely in love you will be willing to sacrifice yourself for that person, you will be devoted to them, in many cases you will put them above yourself. To some parts of ourselves, important parts that do a really good job looking out for us all our lives, this is absolutely awful and horrifying. As this storm rages within us sometimes lightning bolts will fly out, sometimes sunshine. | 0377f277-b303-422f-a473-7399d03a2ff9 |
86nh9p | Why is medicine dosage measured in half-life if half the medicine is still in the body? | It's not used to purely say when a patient has "0" of any drug in their system, it's more to help when giving "Top Up" doses, say you have a patient on Morphine that needs an extra dose, knowing the half life helps Doctors/Nurses decide of they're able to give them a slight dose if they need it.
It's also used when calculating Antibiotic doses, as you need a minimum level in the body to acheive the desired effect, but balanced with potentially overdosing.
For example, if 50mg is the minimum requirement, but each tablet is 100mg, with a one hour half life, the dosage would be:
100mg, wait an hour for it to drop to 50mg, another 100mg which takes it to 150mg, so the next hour/half life only takes it down to 75mg, so if the patient had another dose they would have 175mg in their body and so on. So, if this wasn't kept in check they would soon be potentially overdosing. | d4129a5e-80e6-4e35-a6f0-8c56223b7be4 |
3rfmky | Teresa's daughter Riddle. | There's a couple of things you need to take away. We can work this out similar to how algebra work.
"my daughter's mother" = "me, or my female partner"
So now the riddle is "Teresa's daughter is me or my partner"
If Teresa's daughter is me, I am Teresa's daughter
If Teresa's daughter is my partner, I am Teresa's son in law
Since none of the answers are "Son in law", the answer has to be "Daughter", or B | 41c80170-a851-4e3d-aa34-f888ee60e3f8 |
1dcq13 | The Jets releasing Tim Tebow and why it's such a big news story. | He is a highly prominent player who has now been released.
He is a former Heisman winner (best college football player) who also won two national championships in college. He was also drafted in the 1st round of the NFL draft which would imply that he's a great player with a strong future in the pros (though weirdly, in baseball, hockey, and basketball winning "Player of the Year" usually means you're going to also be strong in the pros, but very often elite college football players - QBs especially - have a tough time making it).
It is also notable because even while he was winning awards and champsionships in college, and even as he was taking his first professional team to the playoffs and winning consistently, people were saying he was not a good QB who did not have a long-term future as QB in the pros
It became apparent that Denver did not have faith in him as a QB, so he was traded to a team with a weak QB situation under the expectation he would get played and given an opportunity to replicate his success in Denver, but he never really got a chance to play (I think he threw 10 passes all year, and didn't start a game and wasn't good when he did play), and then was cut.
In the end, it appears that no one in the NFL thinks he can make it as a QB (since the Jets tried to trade him before they finally cut him) in the NFL, so Tebow will either try to latch on to another team as a backup QB, switch positions (he's extremely athletic so everyone has thought he could make it as a WR/TE, or RB/FB.
He is also prominent because of his dreamy good looks, very prominent religious views, and being generally considered one of the nicest, humble people around. He appears to have star quality on every facet of athletics except actual skill on the football field. | 9d4f2d8f-832e-4c96-879e-f17c3ee0fa19 |
6aiaj3 | What keeps your skin cells in a human shape instead of them reproducing outwards indefinitely? | Oversimplified: Skin grows upward from a base layer - as you go further there's less and less blood supply, and cells aren't supported. The outer surface of your skin is substantially dead cells that form a protective layer.
In the case of injury, other tissues are involved, and chemicals help signal where repair needs to happen. An abscence of those chemicals means repair can stop. | fbb8ce1c-8271-4c8f-8b0c-e77c71738dc0 |
1zg8ah | The "cooling" sensation when eating a powdered-sugar donut. | The process of sugar dissolving in saliva is endothermic (absorbs heat). Since it's such a fine powder, it happens quickly and the effect is noticeable. | 32c77cd7-efa9-4878-a455-e5889dcfa084 |
49bpmi | Why do people have to swear under oath? If they're willing to lie, they'll do it with or without the oath. | If you lie while under oath, you're guilty of [perjury](_URL_0_), which is a felony in the United states, punishable by up to 5 years in prison. If you lie in your day-to-day life, you're just an asshole exercising the 1st Amendment. | ffccaeb8-5d15-46f3-a855-c0b8af2e548d |
151v94 | Can someone explain string theory to me? | Precocious child: "What is everything made out of?"
Science: "Little things called atoms."
PC: "Well, what are atoms made out of?"
Science: "Smaller things called protons, neutrons, and electrons."
PC: "What are those made out of?"
Science: "Even smaller things called quarks."
PC: "What are quarks made of?"
Science: ".........uh, small bits of string vibrating in the 11th dimension. I think. Why don't you go see how well you can hide? I'll count to 100 and see if I can find you." | 37661bb2-e2e0-4b89-af2f-a223c188c231 |
22fe76 | How do game cartridges and video game discs work? | Cartridges have memory chips inside that have the game code stored in them. When you insert the cartridge into the console, metal contacts in the console touch metal contacts on the game cartridge, and they can exchange data via electrical signals. The console loads the game off of the cartridge, and you play.
Discs are covered with lots of microscopic pits that were imprinted on it when it was "pressed", and the console uses a laser to read the sequence of those pits, and turns that sequence into a digital signal.
Cartridges load very fast, but the memory chips are relatively expensive and that limits how much data can feasibly be stored in them. Discs are very cheap to make, and hold a good amount of data, but cannot be read nearly as fast as cartridges. | 95dcfd18-c0b4-45a5-bba4-c26dc53140a2 |
30vj9p | After Charlie Hedbo, people ranted and raved about the importance of protecting free speech, even if it offends people. Now people wants kids expelled and made criminals for offensive things they say it private. Please explain the logic here. | Apart from what /u/Kitworks has said (that it's undoubtedly not the same people complaining), one of the cases you've identified is people being opposed to the *murder* of a dozen cartoonists for the brusque *expression of a political position*. The other is a few people being expelled from a university, not because of their political opinions but because of their bare-faced racism.
The two situations are not the same - it's not contradictory to think that the speech in one of them is more important than the speech in the other and deserves greater protection. | 5a20f2fa-c7ba-4f40-a05b-b698844b62eb |
63253s | How does adware work? | Adware is a piece of Internet connected software that is ether installed alongside something else you installed (opencandy), displays ads as part of the interface (Windows 10 apps, bittorent,) or displays ads outside the program and doesn't make it clear (comet cursor, bonzi buddy)
Sometimes the program sends a request for an ad, or has ads pushed to it. These are a little less frightening, since they simply show you an ad. Other types may change your proxy settings (a proxy is when your computer connects to another computer to get to the Internet, like a game of telephone) and this proxy injects ads into your web pages and may also redirect your search engine to one they made to collect data for more advertising. This one is a great deal scarier, since all traffic is going through a remote computer you were not told it would be going through that could also record your browsing data as well as passwords for things like banks and stores.
Adware itself is mostly annoying, causing your computer to slow down by using its resources to display ads and by.. Well displaying ads when you are trying to use it. The real danger is that this type of software often includes "backdoor" access to your computer, letting the authors install any other software they want for payment. This could mean installing botnet software to attack companies and governments, this could be viruses or malware like cryptolocker which encrypts your files and holds the key hostage or software that uses your Webcam to spy on you to use as blackmail or to upload to a porn site.
In a security conscious environment, it's another program that could be hacked to gain entry to a system. Especially since most Adware isn't written very well.
So if you don't want your mom to find pictures of you stroking your harbl, keep your system clean. This includes your phone, as it's really just another computer. No brand or OS is truly secure against malware, malware sneaks into the app store and Google play all the time and may take days or weeks to be found. | 57b97cdc-2cb8-4150-adf6-da8e798f926a |
2mrw14 | [Biology / botany] How is it possible that some plant species mimic the visual form of other beings, without being able to 'see'? | Random mutation. Sometimes the random mutation results in a look that slightly mimics some other look, which might give an advantage. For instance, something that looks slightly like a predator, might scare away a herbivore intent upon eating the plant.
Thus, that plant survives to reproduce. Others that don't have the look, get eaten more regularly. So over time, more of the 'scary looking' plant's progeny survive, relative to the 'tasty looking' plant.
So, it doesn't "Try" to look like something. It just accidentally does, but since it works, it gets reinforced by survival.
However, some of the examples from the article you link are simply, as it alludes to, cases of pareidolia. It isn't mimicking something. We simply think it looks like it because our brains like to find patterns, and in some cases there is coincidental similarity. | 1b9c7191-167a-4988-903a-1c9d3b49b4d0 |
6otqku | Why do people naturally put on a different voice when they're on the phone or serving someone? | When on the phone you can't see facial expressions or body language so you have to communicate all that information through just your voice. Therefore some people try to use a happier or overly emotional voice in order to be perceived the proper or happier tone.
While serving someone, the idea is to please the customer. No one wants to talk to a grumpy ass hat while trying to buy something so the person providing service puts on a show so they can continue having a job. Sometimes you have a shit day and it would be bad if that reflected. Also, some people aren't confident in their speaking skills so they use a "different persona" in order to overcome the fear | 6b821d21-88ae-4f4c-90c6-444df95259a6 |
ztvat | How does voting for the president work? | Each state is allotted a certain number of votes, based on the number of congressional seats they have. For example, North Dakota, which has one representative and two senators, has three electoral votes. California, has 53 representative (because they have a much larger population) and two senators, for a total of 55 votes. For each electoral vote a state gets, the state assigns one delegate. Technically, the delegates can vote any way they want, but they will vote for whoever the state popular vote goes toward. Some states allow split votes, for example Nebraska in 2008 was split between McCain and Obama. McCain won the state, but per state laws Obama was given one delegate.
Any candidate which receives a majority of the electoral votes shall become president.
Historically the popular vote has meant pretty much nothing, however that is changing with some new laws which say that whichever way the popular vote goes, the state electoral votes will go, regardless of which way the state ACTUALLY votes. In other words, for example (not a real life example) if Texas were to vote for Romney but Obama won the national popular vote, Texas's electoral votes would go for Obama instead.
The biggest reason for keeping the electoral system is that it encourages candidates not to write off small states such as Nevada or Iowa. If it was only a popular vote, 99% of the election money would be spent in states like Illinois, California, NY and Texas.
MOST OF THE TIME though, the popular vote lines up with the electoral vote. I.e., if you win the popular vote, you are extremely likely to win the electoral vote as well. | 1784f091-764d-4901-86dd-9e2c11642296 |
24hsfb | Why do some tests and assessments require that answers are filled in using a #2 pencil? | Because the machine that is used to scan it can only see a certain shade of black. | fb8d292c-bb6b-458b-9c51-1ee1da769067 |
6qi8j1 | How do one-way windows actually work? | They are just heavily-tinted windows. What makes them one-way is that the room that's supposed to be visible is well-lit, and the room that's not supposed to be visible is dark (same way tinted windows on cars hide what's inside).
The window is actually just as visible in both directions. It's placement that makes it work. | aac46bea-3b87-406f-bb17-69fc262bb5bc |
8plnjj | Why is the last percent when charging your device the one that takes the most time? | In general, for charging batteries like lithium ion cells, there is a maximum safe voltage that shouldn't be exceeded (keep in mind batteries can hold a ton of energy, and you don't want that released uncontrollably).
This generally means that as the charging cycle comes to a conclusion, the voltage of the charging circuit increases to a constant level, and because the cell voltage increases after that, the current flowing into the battery tapers off. | bd45c9da-c1e0-4afb-9dc5-dd2ed913e7a3 |
2dlm46 | Is it possible to not get addicted to Cigarettes and Alcohol? | There's definitely a spectrum of people's physiological reaction to nicotine and how addictive it is. Some people just can take it or leave it. I was like you, a social smoker in college and for a few years after. (This was back in the day when you could smoke in bars.) I smoked when I drank, and a "heavy" day for me was maybe ten cigs, but during the week or when I went home for the summers I didn't smoke at all and never missed it. Obviously, you shouldn't smoke (sorry, had to say it), but if it's been two years since you started, if you were going to get addicted at all I think you would have been by now. | d28f4954-2333-42dc-848d-ae4ac2208ebb |
2qq8ev | Why is the hiring practice so much more difficult for minimum wage jobs than skilled labor? | I think part of it is weeding people out. The other part of it is that for skilled labor you usually have some other credentials that make the tests given at DQ pointless. If you have a bachelor's degree from an accredited institution, you should be able to pass a math and literacy test and have proven that you can at least follow university rules well enough to get a degree. That being said, I've seen some companies require ridiculous paperwork like you mentioned and I've seen other places hire minimum wage workers on the spot as soon as they've finished filling out an application. | 9190937e-6cae-4f2a-8c71-a5232272e2ec |
59c9of | Why are people with a lazy eye unable to perceive 3D in 3D films? | 3D films used polarized light to create the effect. The footage is shot with 2 cameras, and projected through 2 projectors with different polarizing filters, one vertically polarized and the other horizontal. The 3D glasses are also filters, only allowing light of a vertical polarization to enter one eye, and light of a horizontal polarization to enter the other eye. The brain combines the images to form an image, and that's where the 3D effect comes together. (Read more [here](_URL_0_)).
From what little I know of Amblyopia (lazy eye), both eyes are still functional, but since the one eye is misaligned the brain ignores the image from it when forming the image in your brain. The two-camera effect is lost, since your brain is only 'seeing' the film from one of the cameras and ignoring the other one. You're essentially watching a standard one-camera production, the only difference being you're watching it through a polarizing filter. | d61e282c-84b8-44c1-9fae-55fa066c4182 |
85u79j | How are professional sports statistics captured? | It's a bit of both. Traditionally stats are collected by the official statisticians - there is usually a team of them (although it depends on the sport.) For instance in hockey one person is responsible for tracking when each player gets onto the ice and when each player leaves the ice, for the purposes of tracking time on ice. All of the traditional baseball stats (batting average, ERA, etc,) can be gleaned from the official scorer's report.
There are more advanced statistics being tracked, like in baseball they are tracking things like launch angles and exit velocities for batted balls, route efficiency for fielders running towards fly balls, etc. That stuff is all computerized (and the MLB buzzword for it is "Statcast") | 673d44f0-2f21-44a8-9885-01ba07e2222d |
5sjpv9 | why are trans fats not completely banned by the FDA? | Several ostensible reasons, such as the fact that trans fats are naturally occurring in some levels in many meat and dairy products, so banning them would mean banning those meats or diary items, which would be both difficult and cause a large uproar from consumers. Also, the federal government doesn't *really* have the authority to do so. They have had to jump through many convoluted hoops and make up laws by the seat of their pants to get things like marijuana made illegal, mostly because banning the possession of things like plants and naturally occurring compounds isn't actually an authority given to the federal government by the Constitution. They have gotten away with it by stretching some Constitutional provisions like the interstate commerce clause to claim that anything that *might* be transferred across state lines, or even something of which it could not be discerned if it crossed state lines or not is presumed to have done so, in order to give themselves the authority to ban things wholesale for the entire country. There is a reason why banning alcohol took a Constitutional amendment a century ago. Back then, things like what the federal government could and could not do were more well understood and taken seriously. Now, not so much.
But the primary reason is much more simple. There is a hell of a lot of money in multi national companies, the same companies that sell hundreds of billions of dollars in products that contain trans fats. Those companies have a vested interest in making sure they're not banned, and have their lobbyists make that abundantly clear to their paid lawmakers. | 21c367df-aa69-4e9e-8f5b-2d3f3aed40e9 |
61r8p8 | All these random pyramid schemes in the US | In the USA, pyramid schemes have long been illegal. Amway was the pioneer of "multi-level marketing" (MLM), and won a regulatory battle against the FTC in 1979: [In re Amway Corp] (_URL_0_). They had been accused of being a pyramid scheme, but the FTC ruled that they weren't. After that, all such schemes could cite the FTC precedent, saying "we're no worse than Amway". They are officially "network marketing" or "multi-level marketing" (MLM) now. It's the USA, where it's important that you have the freedom to make money off of other people's gullibility.
These schemes fall under more regulatory scrutiny in Europe, including the UK. Amway was shut down for a year in the UK (2007) and only reopened after legal action. As in the USA, it hinges on whether your income is dependent on the recruitment of other people: if it is, it's an illegal pyramid scheme. So why are they less common in Europe? I don't have a clear answer on that - it would require a survey of attitudes. But many people are aware that it happens in the USA and see the consequences in the news. | 68b80d5b-d2f5-49dc-9cf5-ff307b956f42 |
u8muf | Why do people think that blacking out their eyes in pictures protects their identity? | Eyes presumably show the most emotion / personality etc of any body part, so we're most likely to remember those, if we see them again.
Also, who blacks out their own eyes..? It's usually done by others to protect the identity of someone. | f8be390c-3d54-4626-9352-3fbc6425e888 |
86wfrs | why do dry erase markers erase themselves if you color over a line you already drew? | The pigment in the marker is dissolved in alcohol. The alcohol evaporates after you write with the marker and expose it to air, leaving the pigment as a dry, solid layer (though easily wiped away). This is why you can't write with dried-out markers. But if you write over the pigment with the marker, it dissolves again in the alcohol you're adding. | 3ecf07c9-016b-4338-b7b1-67798c360976 |
17inkq | Bohr's Theory of the Hydrogen Atom | Basically, the atom was understood like a solar system. Electrons orbiting the nucleus. Bohr suggested that the electrons could only be in very specific orbits and light was emitted when it went from a high to a lower orbit and light was absorbed when it went from a lower to a higher. | 5b084cc2-d8ed-49b5-bdc5-37cdda206b4e |
5gzlir | What does a a lawyer do to defend someone like Dylann Roof | A lawyer is supposed to protect a clients rights. As such, at a minimum, his job should be to ensure his rights are not violated.
The accused should have the right to a fair trial, should not be mistreated, should be innocent until proven guilty and so on.
What makes a lawyer "good" is that they also try to get their clients the best deal possible. The guy might be going to jail for the rest of his life but it's arguably better than death row, and so even in these extreme cases a lawyer can strike a deal. In cases where the client might have a mental illness, the lawyer can shift blame off the individual and get a reduced sentence, this is known as [pleading insanity](_URL_0_).
Imagine I give you an exam book for a subject you've never even heard of and I give you no instructions. It's full of words you don't understand. Then I demand you complete the quiz in a very short time span. You basically have no hope, so we deem that kind of thing unfair. The lawyer does the quiz for you, he's the translator and his intention should be to get you the highest mark you can get. Better lawyers know how to translate your statements into more favorable sounding pleas. They know that the judge is looking to figure out your intent, intelligence, awareness, remorse and chance of re-offending and he will try to guide the judge/jury to a decision that has the best outcome for the client.
Watch Making A Murderer and you'll see how confusing this can all be. | d524408f-ed3d-4f81-b5f9-e57e88052e2e |
7eltho | why do musicals play a medley of the music in the musical at the beginning before things start? | Traditionally the Overture (from French for "Opening") introduces the musical themes used later in a piece like an opera. The Finale will recap them at the end. It's a little like the essay structure Introduction - Body - Conclusion. | f311ce4c-8e2b-4b3f-8c7e-f2645e2cc9c0 |
3oyu29 | Has Russia really decimated ISIS the way some reports suggest? | They've certainly decimated *somebody*, that's for sure. Two things to keep in mind here: One, Russia is conducting its air strikes in cooperation with the Syrian army. This makes them very effective due to the fact that ground forces can move in and exploit weaknesses in enemy positions created by the bombing. The US doesn't support the Assad regime and doesn't cooperate with it, so its bombing doesn't do as much. Yeah, they strike some targets and do some damage, but nothing happens afterwards, there's no follow-up, so the overall effect is less significant.
Two, the US distinguishes between the various armed groups in the region, whereas Russia tends to lump all of them under the label ISIS. It's not a two-way war in Syria, it's a lot more complicated than that. You've got Assad's regime, a bunch of non-ISIS groups trying to overthrow it, and ISIS itself, and everybody's fighting everybody else. The US attacks only ISIS and leaves the non-ISIS anti-Assad groups alone, whereas Russia is squarely on Assad's side and attacks all his enemies, ISIS and non-ISIS alike, and refers to all of them as ISIS. So the Russians might say they bombed ISIS positions when in reality they bombed al-Nusra positions or Free Syrian Army positions or whatever, even though these are different groups that are fighting against both ISIS *and* Assad (and each other). Refer to [this handy map](_URL_0_). Yeah, they've bombed some ISIS positions, but they've also bombed a lot of non-ISIS rebel positions.
Russia claims it's bombing ISIS to make it seem like it's fighting on the same side as the US. In reality the US is fighting against ISIS to take pressure off the other, non-ISIS rebel groups in the hopes that this gives them enough breathing room to take down Assad, whereas Russia is fighting against everybody, ISIS and non-ISIS alike, to keep Assad in power. | e28f3ead-dddd-4f04-98b5-bf6f120a3749 |
25lrf6 | Why does rubbing your eyes feel so good? And is it bad for your eyes/vision? | Optometry student here. I suspect that rubbing your eyes could feel good for many reasons. Allergies is the obvious one. But usually it's because people tend to feel like they have "tired" eyes, especially at the end of the day, which for optometrists that translates into "dry eyes" much of time. Rubbing your eyelids can stimulate meibomian glands to help secrete oils that normally cover your tear film layer. This keeps your tears from evaporating = less dry eye and increased comfort. Rubbing your eyes may also feel good because you are "massaging" the eyelid muscles and purging them of lactic acid (like stretching your leg muscles for example). I have nothing that supports this - it is only my best guess.
Is it bad? Generally no because the eye can take a lot more pressure than people think - your cornea is only 0.5mm thick and to think that it rarely ever gets seriously damaged is astounding. Some theories exists that people rubbing their eyes a lot (oculodigital sign) can be a risk factor for developing a pretty miserable condition called keratoconus, in which the cornea becomes misshapen and may require a transplant after a few decades with the condition. But this might actually be BECAUSE they already have the early stage of this condition and their eyes are irritated from the disease, and so they rub them. The jury is still out. | 910338c2-30b2-4895-ab4d-2eafd3c75d2c |
34mk6n | Why do people advise against using the 1st check in a checkbook? | It's a paper scheme obviously! They just wanna sell us more paper!
Just kidding... I've never had anyone tell me that before. I always use the first check and nothing bad has happened to me. I'm posting here to profile this, so that I can see if I'm being stupid. | 986dc07f-27e2-4d35-819a-351e746ac8c4 |
3y3dx0 | Why can't we use spectrometry to reverse engineer the Coca Cola secret formula? | At most that will tell you whats in the can and the approximate amounts. That information is already printed on the can. It wont tell you the process that was used to mix the ingredients. | 0010754c-3cb7-4d45-9eeb-d459afab85c1 |
7xnvtl | Why is violence in video games acceptable, but sexual violence is an extreme taboo? | Everyone is used to violence and in some cases it’s perfectly acceptable to use it (e.g. when defending yourself). There are no cases where sexual violence would be acceptable, however. | 3d1dbbde-c702-4bcc-96a7-321c57b7af59 |
1wtarg | Why do jokes make us laugh? | A good explanation I have heard (I'm a bit of a comedy geek) is that most jokes *subvert our expectations*. In other words, they lead us to start following a trail of thought in a certain direction, then BAM! we are forced to think in a totally different way suddenly. The element of surprise makes us laugh.
Here's a good article about jokes:
_URL_0_ | 7ca4e9f4-cb64-407c-a6e0-a1ba0bb2a865 |
78yvz8 | How do birds know which direction to fly when they head south for winter? | Many birds have a sense of magnetic field that allows them to know direction and travel to the right place. Many sea turtles also have that sense.
Many birds also have a sense of barometric pressure as well, which is why you can often birds leaving an area before a storm. | e0d08766-57ef-47af-9238-ee783e0a43e0 |
2dhend | Doctors always super-sterilize everything before any procedure, from giving a shot to full surgery. Is this "can't be too careful" or would I take horrible infections from receiving a shot without alcohol wipes? | It's less of a worry about giving you a small infection that goes away after a week or two and more of "we don't want to get sued for $20 million because we gave a guy flesh-eating bacteria with his tetanus shot." | 23921c87-387b-49c7-ba66-8fcc85bfbfb5 |
74mye2 | How does a molecular sieve dry a sorbent | The principle is called adsorption.
Molecular seive is a material with tiny little pores, like activated charcoal. These pores are like the dimples on a golf ball but tiny, nanometers in size.
You make it work by selecting a desiccant with a pore size that matches the size of the molecules you want to absorb.
The pores 'catch' and hold onto the molecules, adsorping them. The forces involved could be van der waahls force, covalent bonds, or just static electricity.
Some molecular sieves can be heated to then release the adsorbate and reuse the sieve. | 5306c575-f8e6-449b-b8b7-0d7767c02d32 |
23has5 | In what circumstances does a president sign a bill while Congress is in session? | If in 10 days the president doesn't sign a bill and Congress is still in session then it becomes a law just like you said. In that case then, the president has three options. They are different in not just whether the bill becomes a law but also in what they mean.
* The president can obviously veto a law meaning he is strongly saying it shouldn't be a law. As long as congress doesn't have enough support to over turn it, that's that.
* The president can sign it meaning he really does want it to be a law.
* The president can not sign it. It still becomes a law but the president doesn't have to show that he like the law. It's a statement more than anything else. Maybe he knows that he will be overturned if he vetos it (which would make him look weak), maybe it's for another reason, but whatever the underlying reasons it's a way for him to basically say "I don't like this enough to put my name on it but I can't/won't stop it." | 0e14bdc0-87d5-49ff-bc99-ca70c09dc308 |
2a316k | What does a movie/TV producer actually do? | For film, producers oversee the entire production of the film. First, they have to acquire the rights to create the film. Then, they have to find someone to write the script (or buy the already written script). Then they have to hire the director to actually create the film, along with hiring the casting director, sound people, actors, etc. Some of these decisions are done in conjunction with the director, while others are not.
In short, the producers are in charge of the business of making the film. | 29e9b047-bd07-4325-9094-d62570a1c371 |
5nnfjf | Why does e^pi*i + 1 = 0? | Probably can't explain at an ELI5 level, but here's the gist of it:
e^angle*i is a rotation of a point in the complex plane (just pretend it's typical "x is horizontal y is vertal" for the moment)
angle=0 degrees means the point (1,0).
angle =90 degrees means the point (0,1)
angle=180 degrees means the point (-1,0). *Pay attention to this one*
angle=270 degrees means (0,-1)
angle=360 degrees means (1,0). You're back where you started.
Here's the deal. In the complex plane, x means "real numbers", y means "imaginary numbers".
so for example (2,7) would mean 2+7i.
So (1,0) means 1+0i (or just 1)....(0,-1) means 0+-i (or just -i) and so on.
What is 180 degrees in terms of radians? Well, it's just pi.
So e^ pi * i = e^ 180 x i = (-1,0) = -1+0i (or just -1).
So now you have e ^ pi * i =-1. Add 1 to both sides of the equation, I'll leave that as an exercise for the reader. | d6f42539-798d-431a-b5be-9544f1de0b72 |
5o61jb | Why does color affect heat absorption? | It's not color that affect heat absorption. It's the physical propriety of material that absorb different wavelenght of light. So if a material absord all visible wavelength of light it will appear black because it doesn't reflect back light into our eyes.
Alternatively, something white is made of something that reflect all the visible light back so we see the color white.
Something that absorb more wavelength will absorb more energy from that light, which will become heat. | 1cb53da0-b5c6-475f-96ea-4cc4908911a1 |
2ygeun | Why is gambling is considered a dangerous vice? | Okay, you're asking two questions here.
1. Why is gambling considered a dangerous vice? Because some people have the tendency to become addicted to gambling and it can engulf their entire life. They will spend every last dime to chase that feeling of winning. In the end though, the house always wins and that's why it's a business.
2. Why can you join the army but not gamble because of your age? Well, it depends on the state (assuming US) you live in, and also the type of gambling. Some states, depending on the form of gambling (lottery, casino, etc.) do allow gambling at 18. The other answer is outdated laws or laws that make zero sense.
You're correct that in some place you may not be allowed to gamble because of your age, but you can enlist to go and possibly die. You are also not allowed to drink or smoke (some states). One can go and risk their life for country, but god forbid they have a beer after work. | c9331ab7-29d8-4504-ab2c-5ca9c94c0aa7 |
1dsa0z | The conflict in the Middle East with Israel and the rest of the Arab nations | This is obviously a super complicated issue, with many conflicting viewpoints. Both sides have their own view of the facts, and even within each side there are many different views.
I’ll give you my own take on this. I’m American and Jewish, but I am fairly sympathetic to the Palestinian side. I grew up learning this story, so my knowledge on the subject is pretty deep, but of course biased. Hopefully someone who knows a lot about the Palestinian view point can chime in here. Please reply in the spirit of sharing your views, not debating and accusing. If you think I've got something wrong, please tell me politely.
**Biblical history background:** According to the bible, and legitimate archeological record, the land in that area was ruled by people who called themselves the People of Israel around 3000 BCE. The city of Jerusalem was first built in this time by King David, and this is supported by the archeological record. Around that time, the Jews built a temple in Jerusalem. In 586 BCE, they were conquered and expelled to Babylon (modern day Iraq). They later returned and built another much larger temple under Roman rule. This temple was destroyed in 70 CE, and the Jews were thoroughly dispersed by the Romans in the 100 or so years following.
I think the above is pretty solid in terms of facts, but the big question under dispute is whether it counts for anything that Jews lived in the land 2000-3000 years ago. Many Israelis argue that there has been at least some Jewish population on the land continuously since that time.
**Rise of modern Zionism:** The modern idea of Zionism (Jews wanting a country on this land) was really kicked off by a French journalist named Theodor Herzl in the 1800s. At this time, the land of Israel/Palestine was ruled by the Ottoman Empire.
After WWI, the land was held by the British as part of the British Empire, and the area was called the British Mandate of Palestine. It was during this time that the Arab and Jewish movements started really competing for rule. Arab rulers from the Ottoman era were trying to negotiate to reclaim the land from the British. At the same, Jews around Europe started immigrating to Israel in a coordinated effort to support the Zionist cause and also flee dangerous anti-Semitic home countries.
**Post WWII and the UN partition plan:** OK, I skipped some important stuff from the British Mandate period, but here’s the main event.
After WWI, there were many colonies held by European powers around the world. After WWII, there began a trend to return those colonies to the natives of the land. Jews and Arabs both claimed the right to the land.
In 1947, the (relatively new) UN proposed a partition plan that would have divided the territory into two states. The Jews accepted the plan, the Arabs rejected it. In my personal view, this is crucial to understanding the current conflict – to me, it says that Jews were willing to live in peace side-by-side with Arabs from the start, but the Arabs denied the Jews had rights to any of the land.
After further lobbying by Jewish Zionists, in 1948 the UN passed a resolution to declare a Jewish state on 78% of the territory (excluded the West Bank and Gaza). Immediately after Israel declared independence, the surrounding Arab states attacked it. Israel emerged victorious and became a sovereign nation.
**Six-Day War:** The last major change to borders occurred in the war of 1967 between Israel and a number of Arab states (Egypt, Jordan, Syria). After years of skirmishes and escalations, both sides were building up forces in anticipation of a war. Israel made the first strike, bombing the airfields in Egypt. Six days later the war was over, with Israel taking control of Egyptian Sinai, Gaza, the West Bank (from Jordan) and the Golan Heights (from Syria).
In the years after this, the Sinai territory was returned to Egypt in exchange for a peace agreement, and Israel made peace with Jordan as well.
**Gaza, the West Bank and East Jerusalem today:** These are the areas that are called the occupied territories. When you hear people talking about Israeli settlements, it is building that occurs on these lands. Palestinians say this is an Israeli attempt to cement their presence in the territories (and that’s a fair point).
In 1993, the Oslo Peace Accords were an attempt at negotiating peace between the two sides. The premise of the agreement would be: Palestinians get a state in the West Bank/Gaza, in return for a halt in violence and recognition of Israel’s legitimacy. The peace process since then has always been based on the same premise, but there have been problems on both sides.
Many Israelis do not want to give up the land, and religious Jews make a point of moving to settlements to hold the territory. Many Palestinians still say that 100% of the land should be returned, denying Israel’s right to exist. Extremist factions such as Hamas actively endorse violence and terrorism to drive the Jews off the land.
And Jerusalem is one of the stickiest points of all. Israel currently holds half of Jerusalem and occupies the other half. Israelis say that if Palestinians ran the area, it would be impossible to defend Jerusalem from terrorism and violence, and that the Palestinians have not shown that they want to stop the violence.
Also, because Israel’s military is massively stronger than the Palestinian’s fighting forces, the violence continues to follow a pattern in recent years. Groups in Gaza launch hundreds of crude rockets indiscriminately into Israel, with only a few casualties. Eventually, Israel retaliates with much more force, targeting weapons centers and known terrorist agents, but inevitably killing many innocents in the process.
Gazans claim that Israel restricts movement of people and goods across their borders, denying them needed materials. Israel claims it must control the borders because Gaza is importing weapons and materials to build rockets. Both sides are true.
Soooooo....it's very complicated and no one has any idea what to do. Israel refuses to keep offering land when they say that Palestinians cannot be trusted to stop using violence. Palestinians refuse to stop the violence because they say that Israel cannot be trusted to give them rights and land. It makes me very sad. | adc3625b-d39e-434c-8849-496da4a69758 |
3ne8xs | if a teenager can be charged with child pornography for having pictures of themselves, why can't they be charged with sexual assault when they masturbate? | Because they've given consent to it as a sexual act. However, if they somehow did it against their own will, then they could potentially sue themselves. Even under the age of consent, they are doing it to themselves. Plus, the only people who could sue in the name of their kid would be the parents. But again, the kid is the one doing it to themselves. Child pornography is illegal no matter if you give consent to someone or yourself, or not. | 1d26cb35-c11d-4387-93fe-1ee7622f9424 |
4n221r | Stephen Hawking theory that information can be lost from the universe when black holes evaporate away | Well, it's wrong because of the word evaporate. When water evaporates, the information of water is not gone. It's transferred to another state of matter. It's only lost in the sense you can't get that cube of ice back, in exactly the way it was frozen, even if you could somehow capture all the water molecules. Honestly, I'm not smart enough to understand how Hawking Radiation works, using it's quantum mumbo jumbo. The only way I can reason it, is to imagine its higher frequency means it isn't as bendable. Like the difference between a tree branch and a steel beam. In that rationale, then gamma rays escape the hole because it can resist the force to bend back upon itself. | 5770ac9a-e611-4a1f-b013-65f8d7488732 |
5476rs | How do they get pure oxygen into oxygen bottles? | Do you mean tanks of compressed oxygen?
There's a few different methods, depending on the purity of gas required. A common method is cryogenic distillation. Basically you make ambient air so cold that it liquifies, then raise the temperature of that liquid just to the boiling point of oxygen.
The oxygen gas will boil off (evaporate) from the rest of the liquified gasses (CO2, nitrogen, argon) and you can capture and compress it to produce pure oxygen. | 1eb1d697-94a4-4791-a321-a305bfb83077 |
1nmc58 | Why do lips, fingertips, toes, etc. get blue when they are cold? | I'm going to go out on a limb and assume the OP is asking why that particular color. Why not yellow or polka dots or zebra stripes? Is there a reason it's blue. | ae3d0a7f-9e1f-4108-82c5-17fbe874330e |
2vlto6 | Why do men and women have separate restrooms? | It is for comfortability. Many people feel uncomfortable with members of the opposite sex around while they are doing their business. It is that simple. | d3fd760f-b625-4161-b6c0-9b24a9b263c8 |
39srd5 | When I'm sitting on my couch and my phone signal switches from 4G to 3G or drops from 5 bars to just 1, what is happening to cause it? | Wireless communications engineer here. There are several things that might be happening.
**TL;DWR** It's probably your network trying to provide service to the greatest number of customers.
Ok, so full explanation: First, and most likely, is that your cellular provider is attempting to redistribute the load on their network. Typically this happens by making less loaded cells appear 'virtually more attractive' making your phone more likely to change which tower it is communicating with and listening to. This is most likely to happen between frequency bands, because the way the energy moves through space is very different depending on frequency. Generally speaking, higher frequencies will not propagate as far.
In my area, for example, AT & T typically advertises their 1900 MHz (high frequency band) 2G cells as 20dB (100x) 'better' than those in the 850 MHz (low) band because they want mobiles that *can* see 1900 MHz band cells to use them, to free up cells on the lower bands for users who cannot. The same thing can happen between 3G and 4G. A network carrier might have a very loaded 700 MHz 4G carrier, and some lighter loaded 2100MHz 3G channels and want you to move to the 3G channels if you are in range.
This might sound like carriers screwing their customers over, but it's really an important construct in cellular networks. It is entirely possible that you will get better data rates with 2 bars of 3G compared to 4 bars of 4G, depending on how loaded the particular cells are. Sometimes, of course, this works to your disadvantage and you will get worse rates, but it generally improves the *net capacity* of the network.
There are also propagation issues, though they are unlikely to cause such dramatic affect as above. It *is* entirely possible that the box truck that just parked down the street is causing an unfortunate reflection resulting in severe multipath interference (multiple signals taking different paths from the transmitting antenna to the receiving antenna as they are reflected off usually metal objects, arriving at different times causing a jumbled received signal) for the great 2100 MHz 3G signal you were getting forcing you to use a poor performing 850 MHz 2G cell. Dead zones in your house *are* likely to be cause by multipath interference however as signals bounce around they destructively cancel in certain areas. Moving your phone can make this effect much more pronounced.
Finally, there are numerous edge cases that can cause this. The network may be taking a cell down for maintenance, or you were associated with a temporary cell. Maybe an emergency call was placed kicking you off the channel you previously had, or a someone with a priority data arrangement requested use of the cell. It's hard to be exhaustive here.
Anyway, I suspect for very dramatic changes (5 bars - > 1 bar, or 4 bars 3G to 2 bars GPRS) the first description is what's happening
**EDIT:** So /u/lostpasswordagain made an amazing analogy in his comment [here](_URL_0_). It doesn't track 1:1 with everything that I said above, but it gets the idea of why this is important down - I'm going to paraphrase here:
Two cities are connected by two highways, a 6-lane highway with a speed limit of 75 mph (4G), and a 4 lane highway with a speed limit of 50 mph (3G). Obviously, given a choice, you would want to take the former. However, given enough traffic, you will reach a point where it would have been better to take the slower highway. In this example, the choice would be up to the driver, but since a cellular provider owns the road (spectrum), they get to make the decision, so they tell each car which highway they are allowed to use to optimize the amount of cars that can get from city 1 to city 2. | 9802a341-4716-4927-85fe-51bc24686c56 |
2b2143 | How do fuel cells in the Voyager 1 & 2 last for 80+ years, yet the fuel in my car won't last a week? | They use these:
_URL_0_
They're great if you need a power source that lasts for years and years and years and you only need to power a radio, a computer and a few other gadgets on a satellite, but they're not great when you need lots of power to drive a car with. | f2abb96e-ddb7-4c47-8e9d-1a84c81fa548 |
59pbz6 | Why do sites choose to go with 'smart' or 'curated' lists (Hulu / Instagram) versus pure chronological or user chosen lists? (Netflix / Twitter)? | Essentially it just keeps you coming back for more. While you could cycle through Hulu alphabetically, there's a chance you don't want to watch 75% of what they have. You don't know exactly what you want to watch, but it's none of that garbage they're tossin at ya. You become fatigued and think, "man, am I really just gonna watch Seinfeld again? Hulu doesn't have any good stuff". You then search random stuff and wouldn't ya know it, they don't have any of that stuff! Over time this makes you think about your entertainment options and decide, Hulu isn't going to have anything, maybe I'll check out Netflix. This is bad for Hulu.
So, they track you and find out what you like. The science isn't perfect yet but they can probably guess what you want to watch (or, see) before you do. This way, every time you go into the app, they're hiding all the options that you have no interest in, and all the stuff you (as they have surmised) like. This makes you come back more often because you're not wading through a bunch of crap. It feels tailored to you, without you even thinking about it.
As far as "posts you may have missed" or "what's new/trending", it may be content they wish to promote, or as simple as advertising to you that it's not the same old stuff, there's a bunch of shiny new media to take in. You take in this new media, believe the app is providing you benefits, and for sites like IG or Twitter, you are branching out and following new people or sharing posts from accounts you didn't know, which keeps business booming.
Sorry for the wall of text, and I'm by no means an expert, but I hope this answered your question. It's tangentially related to what I study, so I took an off the top whack at it. | af9a183a-58e8-4ff1-b3c6-b71d6794387e |
4tz1h3 | Considering that the Earth's atmosphere is more than 75% nitrogen, how do our lungs only breathe in oxygen without accidentally breathing in any of the other atmospheric gases? | In contrast with what a few people in this thread are saying, you do breath in nitrogen, CO2, radon, argon, and anything that is in the atmosphere near you, and it does enter your bloodstream. All gases are pulled into the lungs by decreasing the pressure in the lungs by increasing their volume. So now you have atmospheric air in your lungs, and all the gases dissolve into the blood based on their solubility. Because of hemoglobin, you have a huge amount of oxygen dissolve, and because of a change in pH in the lungs, you kick a ton of CO2 out of the blood into the space of the lungs. Now nitrogen does enter the lungs, but nitrogen gas is not overly soluble at 1 atmosphere, so only a little dissolves (same principle as pressurizing CO2 near a drink to carbonate it, you force extra in at higher pressures, but not a lot dissolves naturally). The Bends is a disease that occurs when using pressurized air at a higher pressure than 1 atmosphere. If you increase the pressure, you force a lot of nitrogen into the blood, and then when you decrease pressure quickly back to 1 atmosphere, the nitrogen is no longer soluble and becomes gas bubbles in your blood vessels. This can happen commonly among careless SCUBA divers. So your body does indeed absorb nitrogen from the atmosphere. Now on top of not pulling in a lot of nitrogen gas into the blood, N2, or diatomic nitrogen is the common form in the atmosphere, and it is highly stable. It is nearly impossible to get it to react spontaneously with anything.
Now for the second part of your question, we do breath in other atmospheric gases. Nitrogen is 78% of our atmosphere and oxygen is 21% of our atmosphere. Together this is 99% of all the gases. Of the 1% left over, 93% of that is argon, a highly un-reactive and stable noble gas. Carbon dioxide is just 0.039% of the total atmosphere, so the amount you do not actually get any of this from the atmosphere, because in comparison with the amount in the blood entering the lungs from the body, it is nearly zero and so CO2 leaves the blood. However, if you artificially raise the atmospheric levels of CO2, then more will be retained in the blood and this can cause problems. For example, astronauts on the ISS and others space stations that do not sleep in a moving current of air will spend the evening exhaling CO2, but since there is no gravity, the CO2 will not sink or rise, it stays in an invisible little bubble around their head. This raises the local atmospheric concentration of CO2, and can cause very nasty headaches for them come "morning".
Source: Multiple chemistry and anatomy and physiology courses. | ff498459-2639-49cd-bd91-36820ea64667 |
56u8nc | why is consumption of meat bad for our climate/environment? | It isn't, really.
The _production_ of meat is problematic when done by people who care about the money but not the animals or environment at all.
But that can be said of anything left to the stewardship of the uncaring.
In resource management terms, eating meat takes ten times as much energy input to get the same food energy on the human plate. So a given range of land _might_ be able to feed ten people on non-meat versus one person on meat.
In practical terms, however, meat isn't that bad a deal as ruminants (cows, bison) and other meat animals (venison, goat, rabbit, pig) can eat much lower-quality fare. A cow can eat grass, and people can eat cows (eating the grass by proxy), but people cannot survive by eating grass. Repeat for things other than grass like ivy and nettles and such. The earth is full of plants that do very well in places, places that are not good for farming, but places that excel at producing plants that are not good human food, but do produce plants that are outstanding for the production of meat.
So you will hear vegetarians making a lot of hay (ha ha) about how meat is terrible and unsustainable. But trying to farm the average cow pasture to produce vegetables and legumes would likely destroy more than it saved. Farming is very intrusive and very tough on watersheds and soil integrity in a way that people with a particular agenda are very fond of ignoring.
So there are plenty of good ways to grow food animals.
But things like Smithfield Ham's disastrously irresponsible farming methods and virtual share-cropping are virtual crimes against animals, earth, and man.
But it's not the meat that's at fault, it's the profiteering dicks being dickish that are screwing the pooch here. | d0a6d161-7189-4431-ac52-d90942d1bf0f |
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