title list | over_18 list | post_content stringlengths 0 9.37k ⌀ | C1 list | C2 list | C3 list |
|---|---|---|---|---|---|
[
"Why doesn't caffeine neutralize carbonated drinks?"
] | [
false
] | Since water becomes acidic when CO2 is dissolved in it and caffeine is a base, why don't they react? | [
"From the MSDS for caffeine ",
"http://www.sciencelab.com/msds.php?msdsId=9927475",
"pH 1% soln/water (10,000ppm/ 9.99g/L)= 6.9 [Neutral.]",
"Carbonic acid",
"http://en.wikipedia.org/wiki/Carbonic_acid#pH_and_composition_of_carbonic_acid_solutions",
"p(",
" 2)= 0.01atm, pH =4.92",
"p(",
" 2)= 0.... | [
"Yes coffee is acidic, while caffeine is a base. The acid from coffee comes from other components like chlorogenic acids.",
"And it should react, just not enough for us to notice. Consider that there's not even enough caffeine in coffee to neutralize it in itself!"
] | [
"What do you mean \"react\"? Acid-base reactions are virtually instantaneous so there's always \"reaction\" going on. Given the fact that caffeine should a weak base, there will be a reaction. However, the concentration is usually way too low to significantly affect the equilibrium of carbonic acid and carbon dioxi... |
[
"Is there an ideal color to reflect light in summer and absorb light in the winter?"
] | [
false
] | I'm building a house in Northwest Arkansas where there won't be much yard for shade trees so I figure I need a very light exterior to keep the house cool. My architect claims that the color green is the ideal color to reflect light in summer and absorb light in the winter. Could the wavelengths of light differ much between seasons to make this true? Also what's the most-ecofriendly roofing material that is not too costly. | [
"Spectral variation of sunlight is minimal from season to season.",
"I just want to be clear for the sake of being thorough: it's not \"minimal\"; it's zero: there is no physical difference between the spectral properties of sunlight in the winter and the summer. OP's architect is quite mistaken."
] | [
"As others have pointed out it is not the wavelengths of light that do this, but the amount of light. Imagine you have a black house with a black roof. During the winter it will absorb more heat than a white house with a white roof. This could lower your heating bills, but during the summer it would increase you... | [
"Thanks again"
] |
[
"Are there any colours that don't exist in nature?"
] | [
false
] | null | [
"Yes.",
"This is true in two different senses: ",
"(1) There are colors that cannot be reproduced by any one wavelength of light. Our color vision system is primarily sensitive to three overlapping wavelength bands, which is why there are three primary colors. The color is set by the ratios between the brigh... | [
"Fascinating post. Do you know by chance what effects psychedelic drugs have on the eye/brain's perception of color? Many users describe seeing colors while on psychedelics that they cannot describe, and do not see in a sober state. Notions of there being more shades of one color, and colors being percieved as more... | [
"The problem with that view is that there are colors which are not reproducible with any one wavelength of light, and others that are not reproducible with any mix of wavelengths of light. Whether those colors \"exist in nature\" is debatable, but they certainly don't exist in the rainbow."
] |
[
"Female Hormones and Virginity"
] | [
false
] | I'm asking to verify something I was told in health class back in highschool a few years ago. I have doubts to its credibility for a couple of reasons, one of which was that the program existed to promote abstinence (and thus I'm absolutely skeptical about anything they told me). Basically, what I was told was that when a female loses her virginity, there's some hormonal response that attaches her emotionally to the guy she lost it to (something over and above what normally happens). I was also told this only happens once. So... -Is there such a hormonal response? -When does it trigger? Is it every time, with every person, or just in some circumstances like loss of virginity? Thanks! | [
"Hormonally speaking, there is some difference between how men and women react to sex. Women produce far more oxytocin which could be considered an attachment hormone. So in that respect it is correct. However, there is absolutely no proof (as far as I know) that it happens more on the first experience and it certa... | [
"Think about claims like this, this way:",
"How many virgins do you think would actually participate in a study like this? What are the ethics involved? Who would fund something like this? What type of experiment would they have to do to accurately study their hormone levels after being de-virgined.",
"All of i... | [
"it could be based on a lot of things. It's completely possible that such a thing happens and has been observed, or inferred from related knowledge of the human brain. "
] |
[
"Do symbiotic relationships between rhizobia and Fabaceae occur in alien environments without inoculation?"
] | [
false
] | Pioneer plants, particularly when chosen for Permacultural applications, are often prioritised for their nitrogen-fixing abilities amongst other benefits. Will these plants fix nitrogen when planted into a non-native areas? Will they form symbiotic relationships with rhizobia they haven't encountered before? Usually when planting legumes, the correct rhizobia is supplied in the form of an inoculant and applied directly to the seed when sowing. For example, if (Siberian Pea Tree) is used in an Australian Temperate zone without inoculation, will the tree adapt to the native rhizobia (or foreign from other inoculated crops) or are the nitrogen-fixing abilities non-existent? Or will they form some sort of relationship, just not the most beneficial? | [
"This is SUCH an interesting question. I wish I knew the answer. ",
"It probably depends on the degree of similarity between the rhizobia to which the plant is already adapted. If \"new\" rhizobia are molecularly/mechanically compatible for the sharing of nutrients, then there would be a strong selection pressure... | [
"At least in Hawai'i and the Galapagos, invasive species can form novel mutualisms with the native rhizobia",
". However, I believe the majority of the time invasive species will vector in invasive rhizobia and maintain their current mutualisms. All of the examples of novel mutualisms that I know of are from th... | [
"The wiki on rhizobia mentions the plant directing competing strains of rhizobia, perhaps indicating symbiosis with multiple strains but these strains may have evolved in the same environment hence similarities and the ability to form with one plant.",
"Unfortunately, my googling can't pinpoint foreign plants and... |
[
"The CDC website states that Tuberculosis (TB) cannot be contracted via kissing, but can be contracted via breathing in TB from an infected person's coughs/sneezes. How does this work?"
] | [
false
] | CDC web page on TB transmission: The CDC website states that Tuberculosis (TB) is airborne, transmitted by expulsion from the lungs/throat through coughing/sneezing/etc., and contracted via breathing. The CDC also states that TB can't be contracted via kissing/saliva swapping. I don't understand how this can be. Why can't TB be spread though direct saliva-airway contact? | [
"Regarding most infectious diseases there are always exceptions, TB is typically transmitted via ",
"droplet nuclei",
" and spread by breathing, talking, sneezing, and coughing and is found in ",
"sputum",
" not saliva. This then has the potential for transmission if they had recently been coughing or if yo... | [
"I think the second part of that article is giving a bit of extra context.",
"It's not that you'd be immune to tuberculosis if you kissed someone with active disease (symptomatic coughing, etc), but if they have latent tuberculosis infection (test positive, bacteria exist within the body, but no active symptoms),... | [
"because your saliva isnt entering your airways but being cleared into your gut (high acidity should neutralize it) and the ciliary mechanism of your airways clear upwards of 90% of debris out and down into your GI. What is infectious in healthy individuals are those minute little bacteria filled droplets that mana... |
[
"Does Cuddling With Animals Release Oxytocin?"
] | [
false
] | I know it's released by mothers and babies when they cuddle, along with couple cuddling. How about when we cuddle cats, dogs, and the like? Thanks. | [
"As a behavioral neuroscientist this is a very interesting question!! Especially since I am writing a paper on oxytocin as we speak :P",
"The closest paper I could find to this is ",
"Nagasawa et al 2009 in Hormones and Behavior",
".",
"Here is the abstract: Oxytocin (OT) has been shown to play an important... | [
"Yeah I'm working from home today.. Ahh the life of a graduate student!\nBut I found that for the first article the n is 55 with 21 males, 34 females. The second article says in the abstract it was 10 men, 10 women :) ",
"I also found a new one that is pretty cool by the same authors: ",
"Nagasawa et al 2011",
... | [
"Very interesting, especially the second article. Do you have know what the samples sizes for either of the articles were? (Not at uni computers so can't check journal articles)"
] |
[
"How would training at 100x gravity effect the human body? (Dragonball Z)"
] | [
false
] | null | [
"Humans cannot sustain anything like a sustained acceleration of 100g.",
"See: ",
"http://en.wikipedia.org/wiki/G-force"
] | [
"I know that rapid acceleration/deceleration are what causes serious damage not neccesarily maintaining high speeds, to make myself more clear I am inquiring as to the effects of humans training/living on a planet that has higher gravity then earth such as jupiter"
] | [
"It turns out that gravity is ",
" equivalent to being in an accelerating reference frame -- that is known as the ",
"equivalence principle",
". There is absolutely no difference between experiencing Earth's 1g and being in a rocket that is constantly accelerating at 1g.",
"Similarly, there would be absolut... |
[
"What are the colorful lines in NASA's Pale Blue Dot image?"
] | [
false
] | null | [
"Sunlight reflected in the camera. ",
"The Wikipedia article explains it in more detail",
". The Sun was just something like 1-2 degrees away from Earth as seen by Voyager."
] | [
"Carl Sagan's speech also mentions the earth suspended in a Sunbeam iirc"
] | [
"Thanks, I've always wondered."
] |
[
"Are people born with different types of brains or are they just clean slates?"
] | [
false
] | What I mean is, are people born with brains that have certain personalities (ex; extroverted vs. introverted) and/or with brains that can do certain things very well (thinking critically vs. something else) or are there personalities developed strictly through experience? | [
"Somewhat boring answer, but both make significant contributions. Much about personality is genetically loaded (your extroverted vs. introverted example is quite high on this actually) but a ton of it is environmental as well (even highly heritable personality traits have significant environmental contributions). T... | [
"I need to qualify your comment, because much of this is speculation. I will explain why shared genes are the predominant explanation for many aspects of your present self (nature), and NOT shared environment (nurture):",
"Much of this debate begins with behavioral genetics, in which monozygotic (identical, 100% ... | [
"from my understanding it is a mixture of nature and nurture. I'm sure someone qualified will hav something more detailed for you soon."
] |
[
"The digits of any base-10 integer divisible by 3 add up to another number divisible by 3. Why is this, and does this happen for other numbers in different systems?"
] | [
false
] | While I was doing algebra in middle school years ago, I was told about this neat little trick for determining if a number had 3 as a factor. I thought it useful and have remembered it since, but now thinking back to it it somewhat baffles me. Does anyone have an explanation? | [
"Let's say we have a number N, and the digits are \"ABCD\"",
"N = 1000*A + 100*B + 10*C + D",
"Now let's subtract the sum of the digits out of this number.",
"N = (A + B + C + D) + (999*A + 99*B + 9*C )",
"999, 99, and 9 are all divisible by 3, so the second term is divisible by three. So that leads us to ... | [
"Do you also know how to square two digit numbers in your head? ",
"Y = X",
" = X * X ultiamtely leads to: ",
"Y = (X-A) * (X + A) + A",
" ",
"So, let's say you want to square 71. It's easier to think of it is 70 * 72 + 1",
" so 70 * 72 = 4900 + 140 = 5040. 5040 + 1 = 5041. ",
"Try it, it's a g... | [
"I do it this way:",
"(A * 10 + B)",
"100A",
" + 10*2AB + B",
"So for 71:",
" 1 = 1^2 B^2\n 14 = 2*(7*1) 2AB\n49 = 7^2 A^2\n----\n5041\n"
] |
[
"Was cooking onions and two frozen chicken breasts in a frying pan with a tempered glass lid. The lid blew and fragmented into little pieces. Why?"
] | [
false
] | I suspect it was temperature related because of the frozen chicken, but I don't understand the physics of it. | [
"The frozen chicken has little to do with it, as it will not make a noticeable temperature differential in the lid - especially compared to conduction between the pan and the lid.",
"What likely happened is that the glass was weakened somehow, through impact of manufacturing defect, and the heat from the pan adde... | [
"Usually you have to ",
" to shatter glass lids. E.g., cover a very hot pot for a long time (boiling water for 10 minutes, say), then take the lid off and immediately run it under cold tap water. THAT will shatter it. ",
"Unless a significant portion of the frozen chicken was in contact with the lid, then no, i... | [
"http://en.wikipedia.org/wiki/Spontaneous_glass_breakage"
] |
[
"How are scientific questions asked about things which happened in the past?"
] | [
false
] | null | [
"A good theory makes predictions.",
"Theories that describe what is happening today do this.",
"Theories about the past also do this. For example, evolution predicted common descent's evidence in the fossil record, biochemistry, genetics, morphology, skeletons, embryos, etc. All of these predictions have come t... | [
"how is this a scientific matter when it's analyzing things that have happened long ago?",
"Well, first because science doesn't necessarily require you to perform experiments; there's ",
" sciences, such as astronomy. The important thing is that you have a theory which is falsifiable. Whether you do that throug... | [
"As a mathematician, I appreciate rigor. In science (or history, for that matter), individual statements about the past can seem speculative or sketchy to me, but the thing that really solidifies them is that many ",
" and ",
" areas of science fit together with remarkable accuracy.",
"As a really simplistic ... |
[
"how near and how fast a passing-by rogue planet would need to be in order for it to be captured by the sun?"
] | [
false
] | (apologies since I am not an expert in this area) so we all know rogue planets right? planets that are ripped off from their orbits by another object so I have this question: Is it possible/impossible for a rogue planet to pass by and be captured in an orbit around the sun? if so, how fast would it need to be going and how near the sun would it need to pass by? | [
"The two older answers are missing a critical point: The Sun alone cannot capture anything. An object either has more kinetic energy than (negative) potential energy - then it is in a Sun orbit already - or more, then it is not in an orbit and won't orbit the Sun. A rogue planet, by definition, is not already orbit... | [
"It is possible, but it’s not a question of how close or how fast. It’s a combination of the two. At different distances, it would need varying speeds (or energies), for it to be captured. An exact answer is non-trivial because other planets can affect it (especially Jupiter)."
] | [
"Thanks mate"
] |
[
"Help me understand aerofoils?"
] | [
false
] | I’ve been watching physics videos on the process by which aerofoils generate an upward force, but the only conclusion I’ve been able to draw is that the equal transit theory is incorrect. From there, each source provides a different explanation that is contradictory to the next. Some say that Bernoulli’s principle doesn’t apply, some disagree, and the coanda effect is also disputed depending on the source. I understand that the aerofoil re-directs the airflow downward, which provides lift to the aircraft, but what I don’t understand is why curved streamlines decrease in pressure when approaching the center of curvature. If someone could clear this up for me it would be greatly appreciated, thanks | [
"Equal transit time is incorrect.",
"However the fact that the lift on an airfoil is primarily due to ",
" forces is correct. The fact that the air speeds above the airfoil are faster than below is correct. And the fact that the pressure above the airfoil is lower than the pressure below is correct.",
"Becaus... | [
"Your analogy with the pipe is pretty much correct. In order for streamlines to be curved, with fluid accelerating in locally circular paths, there must be some centripetal force balancing the acceleration towards the centre of curvature and this force is supplied by a pressure difference, with pressure decreasing ... | [
"The part I’m still struggling with to comprehend is why curved streamlines vary in pressure with respect to the normal. Would it be appropriate to compare it to water in a curved pipe or a centrifuge, where the water at the wall is pressurized due to the centripetal force acting upon it? Another thing is that half... |
[
"Does the amount of fuel I use in my car scale quadratically with the velocity I accelerate to?"
] | [
false
] | Given the formula for kinetic energy, a mass travelling at twice the velocity has four times the kinetic energy. In my car this energy comes from burning fuel which as I understand it is converting potential energy to kinetic. So I must have to burn 4 times the fuel to reach double the velocity. Ignoring energy loss like friction and heat, is this correct? I am confused when I then consider a space rocket. Here I am burning fuel which expands and is ejected. Since I'm ejecting mass backwards at a constant rate the countering force to this is accelerating my rocket forward at a constant rate. So for an observer at the launch pad my velocity must be increasing linearly, and so my kinetic energy is increasing quadratically... which conflicts with my linear consumption of fuel. Where did I go wrong? | [
"The rocket case is called the ",
"Oberth effect",
", and has to do with the kinetic energy the fuel has before it is burned."
] | [
"Thanks for the answers everyone, I'm going to keep thinking through some of the implications of what I've learned here. For some reason kinetic energy isn't something that makes intuitive sense to me. "
] | [
"Imagine sticking a turbine on your car that could be instantaneously set at max power, and that when going top speed you'd be doing let's say 1000 mph. Lets.say you're at a dead stop and flicked power to 100%. Fuel consumption would be constant based on your power setting. You would accelerate until you reached... |
[
"If a cancer has metastasized to the point where it's in several organs before it's discovered, how do doctors know where it started?"
] | [
false
] | You often hear that a patient has, for example, 'lung cancer which has spread to several organs'. How do doctors know that it was lung cancer in the first place? Is it just an educated guess, or are there definite signs? | [
"One: known patterns of spread and parameters of the patient. For instance, a woman in her earlier thirties with tumors in breast, ribs, and brain is most likely to have breast primary with bone and brain metastases.",
"Two: pathology. Take a biopsy, or a tumor excision, and look at it under a microscope. Some tu... | [
"Cells express proteins on their surfaces that are tissue-specific, by looking at what proteins tumor cells are expressing we can make conclusions about where they originated. This is usually done using antibodies that recognize specific marker (surface) proteins."
] | [
"There are different methods to do this. I will discuss the 2 that are most commonly used:",
"First off, before I get into the specifics it's important to realize that there are different theories about tumours and metastases and how they originate. I won't get into the details but it does affect your diagnosis."... |
[
"The RobotRollCall effect: one Layman's transformed notion of time"
] | [
false
] | I'm prepared to be laughed off the stage here. I'm not a physicist and I was never that good at science but after reading this discussion: my brain was set on fire. For quite a while I have been toying with this idea about dimensions and directions: but never really knew where it fit. Now I know that I need to do some reading on relativity theory. However one particular aspect of the original RRC explanation really got to me: it was the idea of drawing a 2 dimensional graph where the y-axis is time and the x-axis is any physical direction. As you move in physical space, you reduce the "time" component of your velocity - you can change direction but not the magnitude of your vector. This was a fantastic way of illustrating why the speed of light is constant. Being without physical mass means is simply an axiomatic definition of not moving through time. To have mass is to have velocity in the time direction! The question still remained, though - why was the magnitude of the vector constant? I started to answer this by doing the same trick with the 2d graph where the y-axis was a direction in the dimension, and the x-axis was any direction in time. I realised that although mass is a 3 dimensional quality, it hurls us into the 4 dimensional co-ordinate system. But mass is not a 4th dimensional quality. We are the of the 5th dimension so we only move through time. We don't slip sideways into completely different time systems (or whatever - my inferior human brain loses the ability to comprehend what that would "look" like at that point). This really blew my mind. I then started thinking, in this 2d graph, why can't we rotate and go back in time? Well, because 100% velocity in space is defined as the absence of mass. Zero mass. So in order to rotate that line any further round in a circle we would need to have negative mass. As far as I know this is an impossibility. Likewise, being stationary is the absence of motion in physical space, therefore 100% of your direction is in the "time" direction on the graph. Why can't we keep rotating past that vertical direction? Because you would have to be . As far as I know this isn't possible. So we have two bounds: zero mass and zero movement. You can still ask, though, what would negative mass ? Mass occupies space - so negative mass would ... destroy space? That's negative space - what about being "more than stationary"? Stationary is the absence of movement in physical space, so perhaps being "more than stationary" would involve the movement of the entirety of physical space whilst you yourself remained stationary, according to some external reference frame. So assuming that "space" is being created by the expansion of the universe and that then movement within space is relative to the rate at which the universe expands, that means that both of our "bounding conditions" are imposed by the rate at which the universe expands - which would explain why we can't change our "4 veolicity" (even though it's not constant, it changes only as the rate of the expansion of the universe changes). Whilst obviously this diatribe wasn't posted in the form of a question, it is really a question: does any of that make sense? | [
"Since you're a fan of RobotRollCall, maybe it's good to re-read ",
"this comment",
". It explains clearly the relationship between the analogies scientists use to explain stuff to laymen, and the mathematics that form the foundations of the actual science."
] | [
"what would negative mass look like? Mass occupies space - so negative mass would ... destroy space?",
"That's an incorrect assumption or analogy. For negative mass to destroy space, it would mean that regular mass creates it. Which isn't true.",
"Mass only ",
" space/time. It neither creates or destroys it. ... | [
"while negative mass would push that bedsheet up from underneath\n(creating an repulsive effect).",
"Wow so attraction due to gravity is just the same as if you put a bowling ball on a trampoline, any objects exerting less pressure on the trampoline would roll towards the bowling ball?! That's also incredible! Ge... |
[
"How do I know that I'm hungry rather than tired? Is there some built-in language for bodily needs or is it a learned response?"
] | [
false
] | null | [
"Ghrelin",
" is a hormone which plays a key role in stimulating hunger. ",
"Fatigue",
" on the other hand is detected in a number of ways since there are varying kinds; mental fatigue for example is modulated by the brain's reticular activating system(RAS). Physical fatigue is triggered by an increase of the ... | [
"Thanks for the explanation. Can you elaborate on Ghrelin? Would you say that it is related to cravings? "
] | [
"http://en.wikipedia.org/wiki/Food_craving#Causes",
"\nThey do not appear to be related."
] |
[
"Why is 2^1023 the last power of 2 that both excel and google calculator can calculate?"
] | [
false
] | I know it has something to do with not having enough bits to calculate on. Can't quite articulate the words to describe it in my head and can't believe it is this low. And why is it that the microsoft calculator app can count higher than 2 If you guys want to see what the actual number is put it into Gives all digits. | [
"It is because Excel uses, as do many other things, ",
"double precision floating point numbers",
". Floating point is a common and a very practical way of representing a large range of numbers in a finite storage space. It stores the number in two parts, the significand and the exponent. It closely resembles t... | [
"They don't."
] | [
"This is really interesting. So I should be able to do a similar calculation on a much smaller scale using a couple of micro controllers like an msp430 right?"
] |
[
"When did humans start finding sex in front of others, awkward?"
] | [
false
] | null | [
"You may need a time machine to answer that scientifically. Behavior rarely fossilizes."
] | [
"All we need to do is find fossil evidence of humans ",
"having group sex in a toxic lake",
"."
] | [
"Or ",
"/r/ Askhistorians",
" due to being way bigger than /r/ askhistory and your question will most likely be answered there than /r/ askhistory"
] |
[
"Why do you heat treat stainless steel?"
] | [
false
] | Is there any benifit it to heat treated stainless as apposed to untreated stainless? | [
"Materials science and metallurgical engineering both cover these topics. Mechanical engineers also learn about some of these topics and I've worked with a number of them in my field. Foundries, testing labs, forges, rolling mills, and many other manufacturing areas need people with those qualifications. Large mach... | [
"There are multiple kinds of stainless steel and the effects of varying heat treatments are numerous. ",
"For example, 17-4 is a grade of stainless steel that when held at elevated temperatures for multiple hours, hard precipitates will form, increasing strength. ",
"In martensitic stainless steels like 440C, y... | [
"Sure, heat treatment can dramatically improve the strength of your stainless steel, depending on the type of steel. Austenitics and ferritics aren't heat hardenable, but martensitics are (that's how you get the martensite). There are also austenitic and martensitic grades that can be precipitation-hardened, which... |
[
"What is stopping us from harnessing electricity from lightning? Is this something beyond our reach?"
] | [
false
] | [deleted] | [
"It's not a peer-reviewed source, but the consensus is clear on this question. Besides the fact that the energy is tough (and expensive) to capture, there's the kicker: there's ",
"just not that much energy in a lightning bolt."
] | [
"Lightning is unreliable and it comes in very brief bursts. Our power grid isn't built to store energy effectively, so lightning wouldn't strike very often and when it did most of the power would be lost."
] | [
"all the lightning in the entire world could only power 8% of US households. At best. ",
"TIL"
] |
[
"Radiation Limitations to our bodies?"
] | [
false
] | null | [
"The \"E\" has nothing to do with radiation, it's just scientific notation (or as they called it, \"computer notation\").",
"6.54E+04 = 6.54*10",
",",
"1.7E-2 = 1.7*10",
",",
"etc."
] | [
"But how does that translate to the exposure limitation that a person must have to each radionuclide? And thanks for the website that you gave me, currently studying how to navigate thru the site but its very helpful."
] | [
"But how does that translate to the exposure limitation that a person must have to each radionuclide?",
"What do you mean? \"E\" has nothing to do with radiation exposure, or physics at all. It's just a way of representing numbers."
] |
[
"What are the practical implications of using solid vs. liquid fuel in rocket boosters?"
] | [
false
] | null | [
"When it comes to chemical rocket propellants, there are definitely some big differences between using solids vs liquids as fuel, with each having its advantages and disadvantages. ",
"Two of the big benefits to using liquid fuel boosters is that firstly, they can produce a higher specific impulse than solid fuel... | [
"And your typical solid rocket booster cannot be turned off. Once you ignite it, it burns until its exhausted."
] | [
"Solid fuel is denser and easier to use. But liquids usually last longer and you can adjust the injection rate.\nThat's why we usually use solids for the boosters and liquid for the main engines."
] |
[
"Why Are the Skills/ Standards of Chiropractors Sometimes Questioned?"
] | [
false
] | null | [
"A reason why they may not get the respect other medical professionals receive is that their practice, primarily, is not researched based. IE they did not arrive at their methods through science."
] | [
"The controversies and criticisms related to and directed at Chiropractic can be read about ",
"here",
".",
"The gist of the issue is that they are presenting themselves as medical practitioners, but have not developed their treatments as medical treatments should be developed - through science. Even moreso, ... | [
"http://www.theskepticsguide.org/archive/podcast.aspx?mid=2",
"\nThere are three short podcasts (91-93) on the topic. It has been quite a while since I listened to them. But they go into the history and science behind chiropractics.",
"\nIMHO the field would go a long way by actually becoming programs under uni... |
[
"Why do clouds always seem to sail so smoothly in the skies, even when on the ground the wind comes in irregular short gusts?"
] | [
false
] | I know there are buildings, trees and what not on the ground, but these stay in place so I dont know if these could make the flow of air so irregular on land. | [
"I imagine it’s because:\nA. They’re so large small bursts are irreversible \nB. The large volume of water has a lot of mass so once it’s in motion it’s momentum keeps it so even if the wind stops briefly \nC. The wind is very different at different atmospheric layers- and even though clouds are still pretty low ov... | [
"The inertia of the cloud has a lot to do with it. ",
"Also, the turbulence is lost because of distance, you can’t see all the little swirls and puffs when you’re ten miles away. "
] | [
"Friction mostly. Air near the ground will hit trees, buildings, etc, which causes areas of relatively high speed air (that has managed to miss things) and low speed air (that has not). Also, air that his something become more turbulent because some air managed to miss slightly to the left, some miss slightly to th... |
[
"I just deflated an old helium balloon. Does that helium just rise and rise and leave the Earth? If so, how long will my helium take to leave the planet?"
] | [
false
] | null | [
"Damned fascinating, either way. Thank you!"
] | [
"Damned fascinating, either way. Thank you!"
] | [
"Helium does leave the atmosphere. I unfortunately don't know the details of the rate at which it does though. Someone more useful will be along I'm sure. You can follow the citation found in this paragraph though to get started.",
"http://en.wikipedia.org/wiki/Helium#Natural_abundance"
] |
[
"If photons are mass-less particles, why are they affected by gravity?"
] | [
false
] | So my understanding of gravity, is the Gravitational force can be described as =(G(m1)(m2))/r Since either m1 or m2 would be 0 with a massless particle, there would be no force pulling the photon towards the sun. Am I thinking about this right? If you normalize the equation to find acceleration, which does not take into account the 0 mass, an acceleration can still be found. Is this the right way to approach this problem? | [
"To explain tonzies's point further:",
"Photons always take the shortest possible path between two points. In flat space, this is a line. Through curved space (like GR describes), the shortest path is actually a geodesic - which appears, to our three-dinensional selves, to be a gravity-like curve. ",
"So they'r... | [
"Photons are affected by gravity because gravitational fields change the shape of space-time. They are then really responding to the space-time's curvature and not the gravitational force as per Newton's Law of Gravitation. This is a key concept in ",
"Einstein's General Relativity",
"."
] | [
"In that case, I am an idiot and I will shut up."
] |
[
"is there a temperature high enough where water goes from ice to gas? (skips liquid stage)"
] | [
false
] | null | [
"It's actually at low temperatures and pressures that increasing the temperature of water can cause it sublimate (go directly from solid to gas).",
"Check out the phase diagram of water."
] | [
"Burning is bad word to use, but dry ice does indeed sublimate (directly from solid to gas).",
"The problem here is that \"dry ice\" is not actually ice. It is solid carbon dioxide."
] | [
"Burning is bad word to use, but dry ice does indeed sublimate (directly from solid to gas).",
"The problem here is that \"dry ice\" is not actually ice. It is solid carbon dioxide."
] |
[
"Is a solid just a liquid with really high viscosity?"
] | [
false
] | Title. If a liquid achieves a high enough viscosity, does it start being considered a solid? | [
"In general, no. A fluid with high viscosity will deform continuously under even an infinitesimally small amount of force over sufficient time. A solid won't.",
"There are composite materials, such as gels, which blur the lines, but only because they're more than one material linked together.",
"Lots of solids ... | [
"No; no matter how long you leave a solid alone, it will ",
" flow like a liquid and deform its shape. Rocks do NOT flatten into pancakes over hundreds of millions of years. Not by themselves, anyway, they have to be crushed or melted or something.",
"Contrast with an actual highly viscous liquid, like pitch (a... | [
"And if you're referring to glass, the idea that it creeps over time is a myth. Old windows were thicker on one side because of the manufacturing technique, and ",
" always installed thickest side down. A historic window with a mix of panes that are thickest in different places is a great disprover of this myth."... |
[
"Do we know instinctively that the feeling of hunger means we need to eat, or thirst means we need to drink? Or do we quickly learn the pattern?"
] | [
false
] | [deleted] | [
"Newborns seem to have the instinct or innate ability to suckle. It typically takes a few days or so for the infant to do it well but the skill is there by birth. Occasional, even fetus' can be found to ",
"suckle digits",
". As noted above, it shouldn't take long for the child to learn that nursing satiates hu... | [
"In cognitive science you sometimes hear of the difference between procedural and declarative knowledge. The OP seems to be asking whether babies have declarative knowledge about thirst and hunger, to which the answer would be definitely no. Declarative knowledge is most likely language-dependent, but in any case d... | [
"I would speculate the newborns may know when they are full. I haven't had children, but my sister just had one and I was there for the delivery. The babies were suckling within a couple hours after birth and they apparently stopped on their own. Or, my sister didn't remove them from the breast until the baby st... |
[
"When scientists say \"The fundamental forces were decided in a fraction of a second after the big bang\", what does that mean?"
] | [
false
] | I apologize beforehand if this question is confusing, I'm having difficulty figuring our how to word this exactly. I've heard this phrase said a number of times before, but I'm not entirely sure what exactly this implies. For instance, the ratio between strong and weak nuclear forces is included in this statement. Are there some conditions in which the ratio would have changed? Essentially, I'm curious about the mechanics of "determining the fundamental forces". Can anyone give a better explanation for this? | [
"What they mean is that some fundamental ",
" were broken in the first fraction of a second, and a single unified interaction between different corpuscles of matter broke, in an accidental way, into the forces we see now. In other words, they're saying that the four fundamental forces we see now are not ",
" s... | [
"Now, that screed should give you a sense of how the electric, magnetic, and weak forces were unified. The strong force ",
" be (and is widely believed to be) unified with the electro-magneto-weak force at high interaction energies, in which case spontaneous symmetry breaking in the early Universe may well expla... | [
"That is precisely what I mean -- or at least that I am speculating: the symmetries of the complex \"superforce\" (or whatever) happened to break the way they did, but they could in principle have broken in a different direction or a different way, yielding different fundamental constants. That may or may not act... |
[
"Why can't an object/ship in stationary orbit just use thrusters to descend straight down in a controlled manner?"
] | [
false
] | null | [
"Because while it has the same angular velocity in stationary orbit, it has vastly different linear velocity. Both are going around 7E-5 radians per second, but the ship is going around 3000 m/s while the surface moves at around 460 m/s. Which means a big change in velocity, its just more effective to use the atm... | [
"It could (though as others have pointed out, you'll need to thrust ",
" to kill your orbital velocity). However, doing so would require incredible amounts of fuel. It's much ",
" more efficient to do two short rocket burns at the start and end of your trip, as in a ",
"Hohmann transfer orbit",
"."
] | [
"How fast you need to be moving in a stationary orbit depends on how far you are from the thing you're orbiting. The further out you are, the bigger orbit you're in is, so you need to be moving faster. Which means, if you're in a stationary orbit and descend a bit, you're now moving too fast for your orbit to still... |
[
"Has Curiosity taken any pictures of the sky on Mars, during \"night\"? I really wish to see into the galaxy from a pollute free planet, or are there other issues?"
] | [
false
] | I just want to know what the sky there looks like. I've traveled to places without light pollution and it didn't live up to the expectations I see on photos, but I wonder how it'd look from there. I was unable to find any myself. | [
"Its not exactly what you want but here is a stunning picture of a Martian Sunset: ",
"http://www.nasa.gov/multimedia/imagegallery/image_feature_347.html"
] | [
"This was all I could find. ",
"http://imgur.com/K3xot"
] | [
"If you just want to see without pollution blurring things up, the ",
"Hubble",
" already does a pretty fair job of it."
] |
[
"Why are the enzymes of warm-blooded animals so special? And what other advantages do warm-blooded animals hold over cold-blooded ones?"
] | [
false
] | Enzymes have a relatively narrow temperature range at which their efficiencies are optimal. Temperatures outside this range can greatly reduce the rate of a reaction or stop it altogether. A creature with a fairly constant body temperature can therefore specialize in enzymes which are efficient at that particular temperature that's why humans can totally fall apart if their body temperature is merely 95 degrees farenheit. But what is so special about the enzymes that make them fall apart at such a high temperature? Also, what other advantages do warm-blooded animals hold? I know they produce more ATP, so this results in more stamina (even though cold-blooded invertebrates can have razor-sharp reflexes). But could this also make them more intelligent? Or more advantaged in some other way? What about animals whose body temperatures stayed around 90 degrees rather than 98 degrees? The Wikipedia article says this: The overall rate of an animal's metabolism increases by a factor of about two for every 10 °C (18 °F) rise in temperature, limited by the need to avoid hyperthermia. Endothermy does not provide greater speed in movement than ectothermy (cold-bloodedness)—ectothermic animals can move as fast as warm-blooded animals of the same size and build when the ectotherm is near or at its optimum temperature, but often cannot maintain high metabolic activity for as long as endotherms. Endothermic/homeothermic animals can be optimally active at more times during the diurnal cycle in places of sharp temperature variations between day and night and during more of the year in places of great seasonal differences of temperature. This is accompanied by the need to expend more energy to maintain the constant internal temperature and a greater food requirement.[2] Endothermy may also provide a protection against fungal infection. While tens of thousands of fungal species infect insects, only a few hundred target mammals, and often only those with a compromised immune system. A recent study[3] suggests fungi are fundamentally ill-equipped to thrive at mammalian temperatures. The high temperatures afforded by endothermy might have provided an evolutionary advantage. Okay, these are advantages, perhaps. Basically, what I'm interested in most are the enzymes and the effects on intelligence/cognitive processing. And most importantly, why do humans have to fall apart at 95 degrees farenheit, when reptiles do just fine on it? | [
"Temperature has a strong effect on the atoms in molecules, like enzymes. ",
"To simplify my explanation, I'm going to use a very simple functional group called an ",
"amide",
". Because of the free movement of the lone pair of electrons present on the nitrogen atom, the C-N bond is rigid (This is called ",... | [
"Mammals and birds do use enzymes that work for reptiles and amphibians, sometimes with changes and sometimes without.",
"For example, Cytochrome P450 is an enzyme that oxidizes organic molecules. It is highly conserved across all species (so much so that I think there are only a few amino acids different betwee... | [
"Oh cool, excellent reply. :) I wonder though - why can't mammals/birds use the enzymes that work for reptiles/amphibians? (aka, the enzymes that actually work at lower temperatures too)("
] |
[
"Hey animal people, do home owned animals get dangerous when they become adults?"
] | [
false
] | I saw that post with the picture of the lion cub in the front seat of taco bell guy's car, and had this question. If I raised my own lion cub from birth to adulthood, is it DNA-wired to be a predator? Would it eat birds and my neighbors cats and eventually my annoying neighbors when it is an adult? Or would it only act as I trained it, so it could just be my really frightening looking house cat? | [
"There is a difference between \"domesticated\" animals and \"tame\" animals.",
"A domesticated animal refers to the whole species. A tame animal only refers to that particular animal. When it is the whole species that has been tamed (i.e. domesticated) then to some extent that species is not aggressive towards... | [
"When it is the whole species that has been tamed (i.e. domesticated)",
"A small clarification, specifically, domestication is the artificial selection for traits that facilitate human use. I don't think most people consider bulls any more easier to deal with than wild bovine species. Taming is raising a single i... | [
"I don't think I'd trust even a house cat not to damage me if it was the size of a lion. Even a domesticated lion (as opposed to simply a tame one) could probably mess you up pretty easily on accident or in a moment of irritation. It's just so big and powerful."
] |
[
"Alkali metals are the most reactive metals. Are there any compounds that are more reactive?"
] | [
false
] | null | [
"This is an impossible question to answer since it depends on what exactly you mean by 'reactive', it's a very broad term. The simple answer is yes, there are many compounds that are extremely reactive. If you're just looking at elements fluorine is very reactive with just about anything it comes into contact with.... | [
"Chemical Molecules have a lot more scope to be \"reactive\" then alkali metals. There are literally infinite chemical molecules. So when we talk reactive we could look at a couple of items:",
"Electronegativity (Flourine is very strong, but you can see a very good table ",
"here",
")",
"Heat of Reaction (L... | [
"As the author of \"Things I Won't Work With\" (mentioned elsewhere in these replies), I agree with the others here that \"reactive\" is a broad category. It's a term that gets used pretty loosely, though, even by chemists (along with \"stable\").",
"We're also biased in that we think of \"reactive\" as meaning \... |
[
"Why doesn't my phone record echos?"
] | [
false
] | While camping at a lake in a small granite bowl with my brother, the wind completely died after a thunderstorm, and the echos of our voices were some of the clearest I've ever heard. There seemed to be very little loss in quality or volume. We attempted to record the event with our phones several times, but only our initial shouts could be heard on both phones (Galaxy 5 and IPhone 6). How did the phones' microphones differentiate between the initial voice and the almost identical echo? Or is there something in the way sound travels that changed it in some way? | [
"Your phone doesn't have any special echo cancelling for voice recording. It just doesn't have the dynamic range and low enough noise floor to capture the echo. Even though it may seem that there was very little difference between the original sound and the echo, there was. Additionally, your phone probably records... | [
"Also possible is that the phone auto-balanced the mic volume when OP shouted and didn't let up soon enough to hear the echos. The echos may have sounded just as loud to OP, but our ears are directional. Shouting goes away from our head (seeming quieter than reality) while echos go toward our head (seeming louder).... | [
"Yes, that's quite likely. More likely than my explanation. The delay in returning to normal record level is called the \"release time\" of the automatic gain control. It is usually a lot shorter than the \"attack time\" which is the time it takes to reduce volume. "
] |
[
"If we localize sound by the time difference of when it it reaches our ears, how do we tell if it's in front or behind us?"
] | [
false
] | null | [
"The shape of your hear/ears affects the sound in a frequency-dependent way (",
"HRTF",
"). The effect is different depending on whether the sound is in front or behind you because your head/ears are not symmetric front-to-back. ",
"Relevant section of the Wikipedia article on sound localization."
] | [
"I only understand rudimentary psychoacoustics, but you left out two important things. You don't just determine the location of sound just based on the time between each ear, but by the intensity difference in each ear and by slight differences in wavelength in each ear due to sound waves bending around the curves ... | [
"I think the question is:",
"If a sound is generated at the same distance directly in front of us and behind how do you know which is which"
] |
[
"What is the science behind “skin tags”? Why do we get them and how come they tend to grow back when they’re removed?"
] | [
false
] | null | [
"Skin tags (aka acrochordons) have a tendency to develop on the body near folds, creases or other areas that may experience constant friction ",
"1",
". This isn't always the case though. Some people are simply genetically inclined to getting them, while others may have predispositions due to health complicatio... | [
"Skin tags occur in areas of friction, but similar to many skin conditions, why they affect only some people (and why some people are more severely affected) is not known.",
"If skin tags are removed properly, the risk of recurrence is low-- but you would be likely to develop new lesions over time."
] | [
"Y'know you really had me in the whole first paragraph and then in the second I felt like I'd never read words before.",
"Joking aside that was super informative, thank you."
] |
[
"When you stick your hand outside of a moving vehicle, are you slowing it down? If so, by how much?"
] | [
false
] | "How much" is very vague and dependent on basically every variable... | [
"Yes (assuming you don't put your foot on the accelerator to compensate). Let's do the calculation, assuming you're in an average-sized car (about 1800 kg in the US) going 60 mph (about 28 m/s). Let's also assume the ",
"drag coefficient",
" of your hand is about 1 (it will depend on how you orient your hand) a... | [
"to add to this, the power wasted by sticking your hand out the window going 28m/s, with a 10N force (didn't double-check calcs above but they seem reasonable), then we get a power of P=f*V = 280 Nm/s = 280 J/s = 280W = 0.4 horsepower. So if your engine is 200 hp, then you are using 0.2% of your engine capacity by... | [
"equivalent to the weight of a 4 kg mass, which is I think roughly about what the limit is for most people holding something using only their wrist muscles, so you probably wouldn't want to stick your hand out of a car that is going much faster than 100 mph.",
"German here. I stuck my hand out of car windows at h... |
[
"Does earth's moon contribute to tides in the liquid core of earth in a similar way to how it creates the tides in surface water?"
] | [
false
] | If so, could these "core tides" influence earth's magnetic fields and also temperature (because of friction?). Also, if the above is plausible or factual, could the lack of large moon orbiting mars have contributed to the cooling / apocalypse of mars when radiant heat from the sun became too insignificant to maintain an atmosphere? | [
"This does happen, but not on a large scale. If you are interested in a large scale environment look to Jupiter and specifically the moon Io. That moon is squeezed so hard by the tidal forces during its elliptical orbit that the planet is HIGHLY volcanic."
] | [
"The moon will indeed have some tidal effects on the movement of the outer core. However, we're still in the process of trying to map the directions and magnitudes of long term core fluid movement, let alone hourly cycles of variation. I'm not aware of any numerical modelling which has attempted to visualise the ef... | [
"I wonder if this is too vague, but does any of this relate to the Tharsis 'bulge', or is it just a particularly striking volcanic feature?"
] |
[
"Why does sugar-free Jell-o need so little powder compared to regular?"
] | [
false
] | If you ever bought sugar-free and "regular" Jell-o, you may have noticed that the sugar-free box is WAY lighter than the regular. Indeed, you can see the net weights vary wildly despite both claiming to make "4 1/2 cup servings": Additionally, the Nutrition Facts panel confirms that the sugar-free powder makes 1/2 cup with 2.5g of power but the regular needs 22g: Apologies for potato quality. I realize that often artificial sweeteners are sweeter than sugar so that could explain the need for less in terms of taste. But it doesn't explain why less powder is needed to jello-ize the same amount of water. Presumably one of the "Extra" ingredients in the SF Jell-o makes the mix more potent...but maybe not? | [
"The weight difference is literally the lack of sugar. The chemicals that solidify the liquid don't require sugar to operate. In normal Jello, the sugar just dissolves in the water and the rest of the powder works to make the jello you're used to. Generally, by weight, you need less artificial sweetener than you ne... | [
"Thanks for responding! It's remarkable that there's (roughly) 10x the weight added in just sugar. But cool! :)"
] | [
"To add, think of it this way:",
"A can of Coca-Cola is 1.5 cups of soda. In that 1.5 cups, there is about 40 grams of sugar. In your jello, for the same amount of water, there's about 60 grams of sugar. So jello is basically a bit more sugary as a soda is.",
"Look at the pictures you posted, see how under norm... |
[
"What caused the extinction of all other human subspeicies?"
] | [
false
] | All evidence seems to point to the fact that modern humans were only one group of many subspecies of humans. Did modern humans simply outcompete/dominate/destroy all other groups, or did they die out for other reasons? What makes modern humans more suited to settling this world than any of our extinct relatives? | [
"It's almost impossible to answer that question because something as simple as a famine or a flood in one area for one year could do it. There could have been a cold snap for a couple years that wiped some out. It could be that we outhunted them or actually hunted them. We don't have enough evidence.",
"It's extr... | [
"Except that we can prove with DNA evidence that we interbred with at least several of these now extinct lines."
] | [
"Interbreeding. Many human subspecies have left DNA in all or some of us. Both Neanderthals and Denisovans have been proven to have interbred with (some of) our ancestors. Most africans don't have any Neanderthal DNA but most of the rest of us do. Almost no one has Denosivan DNA but a small group of islanders i... |
[
"What about a material polarizes light?"
] | [
false
] | You have a beam of randomly polarized photons (assuming all photons are polarized from the start?) which pass through a polarizer (the material in question). The polarizer allows only photons which have a component in the proper direction to pass. For each photon, the probability that it will pass depends on its components in relation to the axis of polarization of the material. This is some of the basic stuff that I know from classes and readings. So what about the material sorts out the "wrong" polarization? Is it a special form of the absorption-emission idea of light passing through a material? Why do some materials polarize when others don't? | [
"A polarizer polarizes by absorbing electrical waves that travel along one axis but not another. That's usually caused by having lines of the absorbing material arranged parallel to each other. In fact, you can make a polarizer for microwaves simply by having thin bands or bars of metal all parallel to each other a... | [
"In addition polarizers are often created using ",
"total internal reflection",
" (see e.g. ",
"here",
").\nThe problem with absorbing type polarizers is that if you want to polarize a high power laser beam the polarizer will heat up very quickly until it is finally destroyed. "
] | [
"Even Polarization on reflection is still this same effect. The component of the waves parallel to the plane of incidence waves go in and out of the reflecting surface and are absorbed. This is why reflected electromagnetic radiation tends to be polarized parallel with the surface. "
] |
[
"What is the best guess on how this new army technology works and could thus be defeated?"
] | [
false
] | null | [
"Do you happen to have a link to where you found this description?",
"Edit: okay, so it looks like the detection method relies on the multi-component nature of most optical systems. Things like telephoto lenses and sniper scopes (the sort of optics that this system would be watching out for) usually have quite a ... | [
"...added; sorry!"
] | [
"So lets assume that is indeed how the tech works (and it seems likely) and then imagine that a) I was able to figure out the wavelength of the pulse b) find a coating to make them opaque to that frequency - if that were placed on a lens, would that then defeat it?"
] |
[
"What's the most 'beautiful' experiment you know of that has been conducted for the first time in the last 20 years? (explanation and details inside)"
] | [
false
] | null | [
"WMAP"
] | [
"While this is thread with tons of potential for open discussion, I'll just point out the ",
"guidelines",
":",
"Questions that aren't answerable by a specific scientific statement (\"What is the most important thing in your field?\" e.g.) may also be subject to deletion"
] | [
"I hadn't noticed that.",
"That's too bad. i really wish I could poll this community on this question.",
"Maybe I should just ask a more general reddit population."
] |
[
"Is it possible to look at the past using almost parallel mirrors?"
] | [
false
] | Let's say you put two mirrors against each other at a slight angle so the if you stare at mirror #1 directly, your eyesight will see a reflection of mirror #2 which will show reflection of mirror #1 which shows reflection of mirror #2 and so on, so pretty much your eyesight bounces from one mirror to another. Now lets say that that the mirrors are very long and the distance your eyesight travels is 600 000 000 meters or otherwise 600 000 km, and at the other end there is a guy standing and waving his hand. Would that cause a lag of 2 seconds on your end from the time the guy waves his hand seeing how light travels at ~ 300 000 km /s? | [
"Also, just to be clear, it wouldn't automatically start showing you what had happened a year ago. The last mirror would take a year to start showing you what was going on when it was put into place.",
"I imagine that's pretty evident, but I just want to make sure that OP realizes."
] | [
"Yes. But it's not actually different than anything else you're looking at. You could look at your own nose and the image would be what it was in the past."
] | [
"Technically ",
" you look at is in the past, right?"
] |
[
"Does a compound exist that releases high quantities of oxygen when heated?"
] | [
false
] | null | [
"On submarines there is something called on an oxygen candle. It's usually a mixture of sodium chlorate and iron dust. When heated, 2 NaClO3 → 2 NaCl + 3 O2. Some of the oxygen then combusts with the iron to sustain the reaction, while the rest escapes to be breathed."
] | [
"Yes. Various chlorates and perchlorates do this. The standard example is potassium chlorate, which is used in all kinds of chemistry demonstrations.",
"Note, though, that a system for chemically generating oxygen can easily become a bomb if formulated or stored improperly."
] | [
"Yep, I read up on oxygen candles after someone else asked a related question around here.",
"And technically, because of that reaction, the source ingredients could be made from salt-water.",
"Unfortunately not a very nice or easy reaction to create using those ingredients, though, but pretty cool that saltwat... |
[
"Do smaller animals see smaller things?"
] | [
false
] | null | [
"If an animal is smaller, that does not necessarily mean it can see smaller things. It may be closer to the item, or the item itself may be relatively larger compared to the creature. To see more detail, the eye needs to have more cones and rods to receive the detail (mostly cones for detail). ",
"For comparison,... | [
"the eagle's eye versus a human eye comparison in this case is not a great example. While it is correct that in order to see more detail the eye needs more cones and rods, it only applies when comparing the sight at the same distance and fov.\nSo sure, the eagle surely can see in greater detail than humans from a g... | [
"Does this also result in eagles having a tougher time at seeing things that are really close to them?"
] |
[
"Industrial revolution: \"Why steam? Why Britain? Why 1700?\""
] | [
false
] | podcast discussing the reasons why the industrial revolution took off in Great Britain. What's your take on this subject? | [
"It was part of the Roman empire by that time!"
] | [
"Steam rises under ambient pressure.",
"By 1700 mechanical technology (from clocks and the like) had gotten good enough that they could use gas expansion for useful work. England had a problem that its mines were flooded and man or animal power couldn't get the water out until Newcomen invented his steam engine."... | [
"http://www.reddit.com/r/history",
"There's a bigger audience there too."
] |
[
"Regarding Dark Energy, how do we know that the redshift of galaxies is due to the expansion of space, and not due to their relative velocity through space?"
] | [
false
] | Being interested in Astronomy and Cosmology, I spend a lot of time watching lectures and documentaries on the subject. But it seems no matter how many of them I watch, they never seem to answer this question, and it's been nagging at me for a while. When it comes to the subject of Dark Energy, these documentaries always give a short of history of how it came to be discovered. It starts with Einstein's theories and his introduction of the Cosmological Constant to make the universe static, and then Hubble measuring the redshift and proving the expansion, causing Einstein to call the CC his "biggest blunder". Then fast-forward to the nineties and Saul Perlmutter and his team using type 1a supernovae to accurately measure redshift of many galaxies, basically greatly expanding on (no pun intended) the Hubble data and coming up with a graph such as this: Then they finish up by saying that this data proves that the expansion of the universe is accelerating...perhaps with some examples involving raisin bread and ants on ballons. It is this last part that brings me to my question and have never been able to find any clarification on. It seems like there could be two possible reasons for the redshift, each leading to opposite conclusions. 1) The redshift is caused by the expansion of space since the photons left the source galaxy, causing their wavelengths to get stretched out. Because the redshift of nearby (but not gravitationally bound) ones is greater than what we would expect given a constant or decelerating expansion, the conclusion is that the expansion is accelerating. Okay, makes sense. 2) The redshift was caused by the relative velocity between the source galaxy and our own when the light left. If this were the case, it would seem to imply that the universe (but not necessarily space itself) was expanding more rapidly in the distant past, and less rapidly in the more recent past. This would also seem to make sense, but is never discussed. (Also, it seems like the redshift being greater than expected for the more nearby galaxies, would also imply that the deceleration of the expansion is decreasing. This would require an explanation just as much Dark Energy would...maybe due to increasing density of the interstellar medium at shorter distances causing friction or some such thing...but maybe my logic is just failing me at this point) Alternatively it seems like it could also be some mixture of the two. So this brings me back to my original question. How is it that the second case was ruled out, whereas the first one was not, especially given that at the time it was the second conclusion that was expected? Let me just say that I'm not trying to argue about this as I'm certain there is a perfectly good explanation for why it is 1 and not 2. I'm simply trying to figure out what that reason is, as I've never been able to find anything that goes into the details and explains it. I'm assuming there must be some sort of complicated math involved and it just can't be easily explained in layman's terms and therefore not appropriate for these lectures/documentaries/etc. as they are intended for the general public, so if you have to get a little technical for this answer I completely understand and will try to follow along anyway, but keep in mind I am a complete layman myself. Thanks! | [
"There is already a large amount of discussion, ",
"including very similar questions in our FAQ",
", reddit's search algorithm is fairly terrible though. So I'll give a brief answer.",
"First thing we need to clarify is that you are conflating two things, the expansion of the universe and the accelerating exp... | [
"Imagine how it would look if, no matter where you sit in the universe, the rest of the universe always looked like it was moving away from you. What would that universe look like?",
"I'm at position 1, and I see people at position 0 and at position 2 both moving away from me. The person at position 0 must see me... | [
"Thanks for the reply, and I am sorry if I worded it incorrectly. I actually did look through that entire FAQ before posting, and did a search as well, and did not see the question anywhere. I was not trying to question whether or not the universe is expanding, or suggesting that we are in the center. I only mentio... |
[
"A question about capacitors and batteries"
] | [
false
] | I've been reading up on these two devices and was wondering if someone could clarify something for me. I understand that batteries are more energy dense than capacitors, but I'm still not quite clear on why exactly this is. If it is a matter of size (minute chemical reaction in a battery as opposed to the relatively larger dielectric/metal combo in a capacitor) could a capacitor that was created using a CVD process to deposit alternating layers of dielectric and metal films approach the energy density of batteries? | [
"The alternating later structure you describe woul essentially be a large number of capacitors in series and would have the same or less capacitence than a single capacitor with a dielectric of equivalent quantity and. total thickness. It would also have problems shorting because the dielectrics would be so thin. T... | [
"If you simply make a layer by layer structure A|B|A|B|A|B|A and measure perpendicular to the layers then, yes, it'd be a series of capacitors. What you really want to do is make an multilayer structure where the metal acts like interdigidated fingers. That's the whole basis behind ",
"multilayer ceramic capaci... | [
"Some technologies that behave like capacitors (discharge quickly) are not in fact anything like traditional capacitors. Can you link me to the technology in question?"
] |
[
"Do electrons change their \"orbital\" shape when they gain or loose energy?"
] | [
false
] | null | [
"Different orbitals have different shapes, generally speaking. So when you promote the electron into a different orbital, you're changing the shape of its wavefunction."
] | [
"The wavefunctions get a little more complicated in a solid-state situation, relative to isolated atoms. Wavefunctions in the conduction band look very different, as electrons are more or less free to move around."
] | [
"Thank you. I wonder if the orbital shape has anything to do with conductivity. I understand it's all about valance electrons. I just wonder. Hmm."
] |
[
"Could you see distant stars as vividly as we do on earth if you were just floating in our solar system?"
] | [
false
] | I see a lot of pictures of the upper atmosphere where it is just black beyond the earth. It looked the same in the picture of earth from moon. If I was just orbiting our sun in relatively empty space in our solar system, could I see all the distant stars and bodies we see on earth every night? Why or why not? | [
"The answer is yes, you could. If you were orbiting the sun, your observation point would be free of an obscuring atmosphere, giving you a wonderfully clear view of the surrounding space. However it is important to realize that Earth is doing this exact thing. The only difference in view between earthbound-you and ... | [
"Space looks black (with no stars) in those pictures because the Earth, the moon surface or some other object (ISS, space craft, astronaut) is being lit by the sun. Since camera have a maximum dynamic range, exposing it for the background stars would mean the foreground objects would be seriously overexposed and wa... | [
"In space no one can hear you scream - but they can definitely see you!",
"Light doesn't need a medium to travel through (obviously - otherwise no light would ever reach the Earth in the first place), and the light travelling through space is not much different than the light we see on Earth. For the most part, a... |
[
"Do robotics engineers and A.I. programmers take any precautions against a terminator type revolution?"
] | [
false
] | null | [
"Nope. None at all.",
"True AI is still so far away that it is inconceivable on the equipment we currently have.",
"I suppose we still have ultimate control even if something unforeseen happened by the simple expedient of hitting the power switch or pulling the plug."
] | [
"My research might actually rank relatively high on the \"likelihood to cause SkyNet\" scale - I'm working on getting a robot that can wander around on its own to come up with its own things to do when no one's given it a job - and yeah, as Zerowantuthri said, current robots are so far from SkyNet that imagining an... | [
"If you've ever worked with a robot, you would know you have pretty much nothing to fear from them.",
"Generally, they can be knocked over and killed with a gentle push, or destroy their circuits by accidentally touching them.",
"Large industrial robots would be capable of killing you, but they'd have no way of... |
[
"Can you smell and/or taste minerals in wine?"
] | [
false
] | I'm taking a degree in wine in Norway and my professors can't agree upon whether or not you are able to taste and/or smell the minerals the wine has taken from the soil. Can you help me and my class mates in this? | [
"But in beer the water and its contained minerals is a primary ingredient.",
"A better analogy is would you be able to taste the soil that you have grown the grains and hops that you use to make the beer."
] | [
"There is no scientific evidence that minerals in the soil will be present in the wine. ",
"Minerals in the soil do influence plant growth though and thus ",
" be an influence on the juice from the grapes. But characteristics like \"flintiness\" are often caused by reduced sulfur compounds that are not drawn f... | [
"In my beermaking experience you can most assuredly taste the impact of the carbonate levels in the water you use on the final product. ",
"So I would 'guess' that it would stand to reason that if your in an area with particularly high levels of carbonate that it might affect the final product. If you see the lin... |
[
"Are there any other energy sources for ecosystems apart from the sun?"
] | [
false
] | [deleted] | [
"You will likely hear about ",
"chemosynthesis",
", the energy source at hydrothermal vents.",
"I would like to point out, however, that the chemical gradients that result in reduced chemicals as an energy source result from the fact that seawater is oxygenated. Seawater would not be oxygenated without plant... | [
"As Wrathchilde pointed out, there are many organisms that are chemoautotrophic, meaning that they are able to fix carbon, and get the energy to do so from chemical compounds, rather than light as photoautotrophs do. An excellent example of such organisms are the bacteria/archaea that live around deep sea hydrother... | [
"Thanks, although if anyone knows any other sources (especially ones independent from photosynthesis) I would like to hear about them."
] |
[
"How much advantage do you get from air launching a rocket?"
] | [
false
] | I know there are some advantages in launching a rocket from an airplane. 1) Launch anywhere anytime, less concerns with weather etc. 2) Launching at about 40,000 ft get's you out of the dense lower atmosphere 3) You get the velocity of the launch aircraft to assist you. But is there any way to approximate how significant these advantages are? Like the Pegasus rocket is launched from the air and it can carry about 1000lbs to LEO. Could this rocket even reach orbit empty if launched from sea level? About how much more fuel would be needed to carry 1000lbs to LEO if they weren't air launching it? Pegasus : | [
"Air launching an orbital rocket",
" offers many advantages, the greatest of which is the fact that orbit can be reached with a significantly smaller vehicle. Initial lift through the first 40,000 feet of atmosphere is provided by an air-breathing aircraft, so that portion of the flight doesn't require on-board o... | [
"Wouldn't change a thing, you still have to get the rocket up to altitude in the airplane and that will require even more fuel, so you won't get any advantage from it. Moreover, there are no aircraft capable of carrying most space rockets."
] | [
"In what way is it less efficient? The aircraft is totally reusable with the exception of the jet fuel, which is by far the vehicle's cheapest component. Also, since an aircraft is air-breathing, no oxidizer (such as peroxide or liquid oxygen) is required. For appropriate-sized payloads it is the cheapest way to ge... |
[
"Single cell organisms"
] | [
false
] | [deleted] | [
"That's more of a philosophy question than science - it simply depends on how you view that common ancestry. Also, trace the ancestry back even further and we shared a common ancestor with plants as well - so by your argument, eating anything living at all would be cannibalism. Just some proverbial food for thoug... | [
"All life probably descended from one type of organism, the ",
"Last Universal Ancestor, or LUA",
".",
"However, this includes plants, so if you're going to abstract the idea that far back, vegetarianism is no different from omnivorism."
] | [
"scientifically speaking, am I right?",
"This is not a scientific matter. It is a cultural matter, one of definitions and moral standards. The definition of \"cannibalism\" is subjective and non-empirical."
] |
[
"How real is the prospect that one day an AI that will overcome us, as in what happens during the last episode of Silicon Valley?"
] | [
false
] | null | [
"Hi funkdoctorspock1 thank you for submitting to ",
"/r/Askscience",
".",
" Please add flair to your post. ",
"Your post will be removed permanently if flair is not added within one hour. You can flair this post by replying to this message with your flair choice. It must be an exact match to one of th... | [
"Computing"
] | [
"'Computing'"
] |
[
"Does the human eye see in frames per second?"
] | [
false
] | null | [
"\"The temporal sensitivity and resolution of human vision varies depending on the type and characteristics of visual stimulus, and it differs between individuals. The human visual system can process 10 to 12 separate images per second and perceive them individually, and sequences at higher rates are perceived as m... | [
"Please see the FAQ, the answer to this question is under the neuroscience section"
] | [
"Yes, but not all motion is equal. I can easily see the difference between a 30fps video and a 60fps video. Is there a point beyond which the difference in frame rate is imperceptible to the average human eye?"
] |
[
"Is it possible to work out the probable angles between two molecules bonding in 3D space, or are their shapes just like we draw them on 2D paper?"
] | [
false
] | What branch of chemistry is this? Are there some good resources to learn about this or is it all just supercomputing now or something? | [
"Are you referring to ",
" interactions (bonding between two distinct molecules)? The geometry of those interactions are very hard to predict, because the weak bonding involved is not quite as directional as in actual covalent bonding. "
] | [
"The bonding angles depends on the type of bond and what other bonds or lone pairs of electrons are present at a given atom within as molecule. The idea is that the the stuff around an atom likess to spread so they are the the farthest away from each other they can be."
] | [
"A college-level general or organic chemistry textbook is probably the easiest introduction to bond angles. Organic chemistry is especially useful, because it teaches how bond angles affect and are affected by organic reactions.",
"",
""
] |
[
"My 4y/o told me her dream about losing teeth without ever knowing it's a common dream. Are there any other examples of cross-cultural phenomena that centers on a specific narrative?"
] | [
false
] | null | [
"I always have these bizarre dreams where I desperately have to use the washroom and have to settle for a lone toilet sitting out in the open -- in the front window of 7-11, in St. Peter's Square, in an office lobby just as a car crashes through the plate glass -- all kinds of weirdness. When we talked about such ... | [
"Similarly, the experience of getting \"domed\" on DMT often involves going to a cavernous place and meeting diminutive creatures (gnomes, elves, sprites, etc.) that eagerly ask you to entertain them. Eventually they tire of you and demand more, before sending you back out of the \"dome\"."
] | [
"Similarly, the experience of getting \"domed\" on DMT often involves going to a cavernous place and meeting diminutive creatures (gnomes, elves, sprites, etc.) that eagerly ask you to entertain them. Eventually they tire of you and demand more, before sending you back out of the \"dome\"."
] |
[
"Do fully vaccinated people who still get COVID have the same level of infection as an unvaccinated person?"
] | [
false
] | Just wondering if there’s any research on whether or not symptoms are milder for fully vaccinated people. Me and my girl are double vaxxed and both shots were moderna | [
"Recently attended a lecture by Dr. Kizzmekia S. Corbett who was a researcher on the mRNA covid vaccine. She discussed how the vaccinated who get infected carry a smaller viral load in their nasal passages, not down in their lungs, whereas with the unvaccinated the infection gets further into their lungs and respit... | [
"Gonna comment on the Delta variant, since it's the most prevalent now:",
"In terms of viral load and all that jazz (what comes out of you and can infect others), see the other comments like ",
"this",
" and ",
"this",
".",
"",
"In terms of symptoms and risks to yourself, you are much more protected ... | [
"Symptoms and illness severity are dramatically reduced with the vaccine. Additionally, after the first few days of infection the viral load is much lower, which means a lower rate of transmission to others. Although some people are getting breakthrough infections due to the delta variant, the risk of hospitalizati... |
[
"Does antimatter interact with light the same way matter does?"
] | [
false
] | If we were able to build macroscopic structures using antimatter, would we be able to see them? Would they look the same as the equivalent structure made of regular matter? | [
"we expect it will. One of the big benefits of the recent CERN news about trapping antihydrogen for 1000 seconds is that we hope to start doing spectral analysis of anti-atoms to confirm that they have the same properties as atoms."
] | [
"Eh, finding it in space is trivial. You need to look for the signature gamma radiation for matter-antimatter annihilation. It's more about confirming what we already expect from theory. Although, if it was different than maybe we could say something about the early universe matter anti-matter asymmetry. But I don'... | [
"What are the uses of knowing the spectrum of anti-matter? Being able to identify the locations or possible concentrations of it in space?"
] |
[
"Accelerating through a turn on a motorcycle."
] | [
false
] | I recently took a motorcycle safety class where I was told that a motorcycle gets more traction when accelerating through turns, which matches my experience of feeling more stable when accelerating through turns. However I seem to remember from high school physics that there is a certain amount of friction available to the tires, and braking takes some of that friction away from turning. It seems like accelerating would also take away some of the friction, because it's also a change in velocity...just the opposite sign. Am I actually more stable if I accelerate through turns? Edit: Thanks for the explanation all! | [
"As commonly known, moderate accelerating puts more downward force on the rear tire which equals more available friction. But why does that help?",
"A motorcycle + rider's mass distribution is towards the rear. In a steady state turn, the rear wheel will probably slide first due to various factors, but one being ... | [
"When you accelerate, it shifts the weight to the rear wheel. This compresses the rear suspension and pushes the rear wheel into the pavement, as well as taking some weight off of the front suspension. The front wheel (having a limited amount of friction) can use more of that friction for turning. There's an arg... | [
"When you accelerate, it shifts the weight to the rear wheel. This compresses the rear suspension and pushes the rear wheel into the pavement, as well as taking some weight off of the front suspension. The front wheel (having a limited amount of friction) can use more of that friction for turning. There's an arg... |
[
"How difficult is it to build nuclear weapons if you already have the means to build power plants?"
] | [
false
] | I always thought that as soon as a state has the infrastructure to build nuclear power plants in place, it would be very easy to arm itself with nuclear weapons. How long would it take, for example Germany, from the political decision to screw the relevant treaties to the first test? | [
"The soviet union took 4 years to build their first nuclear weapon from scratch, no power plants or anything. India did it from scratch in 7 years by quietly employing 75 people, and went thermonuclear a few short years after that. France did it in two years, and it has only gotten easier than ever before what with... | [
"Every industrialised nation with nuclear reactors could make weapons, but Germany and Japan are considered as the most capable potential nuclear states. They do active research in nuclear science and engineering and research and their expertise in nuclear non-proliferation issues is not different from the experti... | [
"Take at least ",
"780 kilograms",
" (pdf file) of 20% enriched uranium 235, slam 2 noncritical mass chunks of them together in a ",
"gun type assembly",
" and you have a crude nuclear bomb.",
"This is why most the world is concerned about Iran enriching uranium to 20%.",
"A lot of people don't realize ... |
[
"How does one explain the complexity of single cell organism's eventual evolution into multicellular organism?"
] | [
false
] | My roommate was trying to explain evolution theory to his girlfriend and we were not able to sufficiently articulate the process by which something as simple as a simple celled organism can eventually evolve to have specialized cells, tissue, and eventually organs. We were trying to explain that there was no "inclination" to evolve, but rather that evolution (and life itself) is merely a series of countless accidents that happened to result in one specie dying where others did. Clearly the issue is that she doesn't understand the massive amount of generations that contribute to the most minor of changes, but the fact that my roommate and I were somewhat flustered simply trying to explain that the human body is too perfect to be an accident was a bit unsettling. We don't mean to refute her for the sake of being right (I'm unsubscribed to for a reason) but it would be nice to have a more succinct answer. | [
"read this ",
"http://www.scientificamerican.com/article.cfm?id=test-tube-yeast-evolve",
"seriously."
] | [
"Thanks!"
] | [
"You can start at the cellular level with the ",
"http://en.wikipedia.org/wiki/Endosymbiotic_theory",
".",
"Basically from this point up to human size, cells specialize and work together as its more efficient to do so. So your inclination to evolve comes down to efficient use of energy."
] |
[
"AskScience AMA Series: We are Dr. David Parrillo and Jeff Wooster from the Dow Packaging and Specialty Plastics business, here to sort out the facts from fiction on plastics packaging as it relates to sustainability, AMA!"
] | [
false
] | Hi Reddit! Innovation in plastic packaging has been driven by new materials development and enhancements in machine processing technology. The growth in flexible packaging is apparent in local super markets. In the US alone, the flexible packaging industry is worth roughly $31.1 billion. Significant innovations in material science (for example, advances in Polyethylene catalysis) have enabled new packages to be developed with multiple individual plastic layers that have the toughness, abuse properties, hermetic seal properties, barrier properties, and the shelf appeal to drive the conversion from high cost and high CO2 footprint materials to Plastic Packaging which enables a improved system sustainability. When compared to other packaging options, plastic packaging is often more sustainable. If you’re wondering why and how plastic can be so good when common perception would dictate just the opposite, join this conversation! We’ve spent decades collaborating and developing product, process and policy solutions to deliver a more sustainable future. Ask Us Anything! We’ll start responding to questions at 1:00 PM Eastern Time (10 am PT, 6 pm UTC.) : I am a PhD chemical engineer from the University of Pennsylvania and a Global R&D director at Dow. I am a member of the Materials Research Society Board of Directors, the External Advisory Board of Chemical Engineering at UC Santa Barbara, and a member of AIChE. I have more than 21 years of experience in the Chemical Process and Materials Industries driving product innovation in numerous market segments. I hold 13 US Patents and am the primary author on 20 peer review publications in the scientific literature. : I am a chemical engineer from Iowa State University and a global Sustainability director at Dow. In this role, I work with the entire value chain to drive the use of science and data-based decision making to improve the sustainability of plastic packaging value chains. As part of my effort to collaborate across the industry, I serve on the Board of Directors and as the president of AMERIPEN, a trade association founded on the principle that decisions should be based on scientific data and on the Board of Directors for GreenBlue, an environmental non-profit dedicated to improving sustainability. After spending the first 19 years of my career in R&D, I have spent the past 8 years focusing on sustainability. I hold 45 U.S. and foreign patents and have published more than 50 technical papers and presentations. | [
"If your monomers are derived from fossil fuel processes, by definition your materials are unsustainable. Polyethylene requires ethylene, derived from fossil fuels. It can also be produced from the dehydration of ethanol, but that sounds like taking something valuable and turning it into something much less valu... | [
"Can you please give a comparison to other packaging options and show why/how plastic is more sustainable? Also how about plastic grocery bags and the banning of them?? Do either of you have an opinion on this?"
] | [
"Is most plastic packaging made directly from crude oil, or is it mostly recycled from existing plastic? Since I assume it's not 100% from recycled plastic, why not? Is it low recycling rates? Technical limitations on what recycled plastic can be used for? I meticulously recycle every bit of plastic that comes into... |
[
"Is light made of particles, or waves?"
] | [
false
] | This comment by RobotRollCall got me thinking: "In a sensible, physically permitted inertial reference frame, the time component of four-velocity of a ray of light is exactly zero. Photons, in other words, do not age. (Fun fact: This is why the range of the electromagnetic interaction is infinite. Over great distances, electrostatic forces become quite weak, due to the inverse square law, but they never go to zero, because photons are eternal.) "In the notional reference frame of a photon, all distances parallel to the direction of propagation are contracted to exactly zero. So to a photon, emission and absorption occur at the same instant of time, and the total distance traveled is zero." This sparks so many questions. Light is emitted radially from the sun, so does that mean that, if the range of electromagnetic radiation is infinite, an infinite number of photons are sent into space in all directions, just waiting to interact with something a billion light-years away? Wouldn't a wave-like definition make much more much more sense in that situation? Honestly, I've never been convinced that light is made up of particles... tl;dr What the F are photons? | [
"Let's start with the first question — light, is it a particle, or a wave? As it turns out, light exhibits properties of both. Let's take these two ways of seeing light individually. I'm going to take this ",
" slowly, so feel free to skip some of this stuff if you already know it.",
"I'm hoping everyone here k... | [
"The best way to think about these things, really, is not to think of them as ripples in a pond nor billiard balls flying around in space, but instead as a flow of ",
". In the half-silvered mirror experiment (without the sensor), don't think of it as \"the photon has a 50% chance of being reflected or not reflec... | [
"Photons are particles. Period. End of paragraph.",
"To be more specific, photons are massless, uncharged vector bosons. They have no mass, no electric charge and a spin quantum number of 1, and they obey Bose-Einstein statistics. The behavior of photons is ",
" well understood, and is essentially the same as t... |
[
"Will the forces that is expanding the universe ever get strong enough to expand the space between atoms atoms?"
] | [
false
] | null | [
"The strength of the force needn't change, but it could be that spacetime itself expands so fast that the forces can no longer hold atoms together. This is called the ",
"Big Rip",
".",
"About 60 million years before the end, gravity would be too weak to hold the Milky Way and other individual galaxies togeth... | [
"There isn't a force expanding the Universe, there is a force making the expansion accelerate, and it's due to dark energy. This force acting between two objects a given distance apart (such as nucleus and electrons) is a constant in time, it does not get bigger. It's very small."
] | [
"Ah right, i misunderstood it then. Thanks!"
] |
[
"How come it takes electrons lots of energy to approach the speed of light, but electricity travels near c?"
] | [
false
] | I understand electricity is a flow of electrons, which is why I'm curious about the relative slowness of individual electrons. Feel free to point out and mock any fundamental misunderstandings, but I would prefer education! | [
"Electrons in conductors actually move really slowly, like millimeters per second. However, the electric field around the electron propagates closer to the speed of light. To make an analogy, if you had a tube full of marbles, and you pushed a marble at one end, the marble at the other end would get pushed out long... | [
"Electrical signals",
" are the consequence of collective flow of electrons. Even though individual electrons travel rather slowly (they random walk with a drift speed that's of order mm/hr in conductors), the signal resulting from a bunch of them moving in concert travels much more rapidly. For instance, for cop... | [
"That's a great analogy! Also, just to add that when people mention the ",
", they're not talking about the ",
". They're talking about the speed of the electromagnetic field that moves through the wire, which makes electrons jump from one atom to the next. The speed at which information is transmitted through ... |
[
"Why does heart rate increase so dramatically after blood loss? Surely 25% blood loss should only require a rate increase of 25%"
] | [
false
] | If a person looses 25% of their blood, their heart has to work 25% harder to maintain an acceptable cardiac output (amount of blood per minute). At the same time, the body's blood vessels constrict to maintain a normal blood pressure. What I cannot understand, is why in practice the heart rate increases by SO MUCH. The literature states clearly that 25% blood loss will result in a heart rate > 100 beats per minute. And this seems to correlate with clinical experience. But why? If the person started with a normal resting heart rate of 60, a 25% increase = just 75 bpm. A heart rate beyond this will INCREASE cardiac output, and negate the need for vasoconstriction, which is the opposite of what is supposed to happen when a person suffers a bleed. What am I missing? Why does the heart rate increase by so much? | [
"In blood loss greater than 20% the vasoconstriction is not able to maintain the normal blood pressure, because it could cause ischemia in your legs/arms and organs that are perfused by small vessels. Also the heart must centralise the blood to most important organs like brain/heart/liver to keep you alive and with... | [
"Because having 75% the amount of blood means 75% as many red blood cells able to carry oxygen (which it receives at the lungs via gaseous exchange). But there is still 100% the amount of cells throughout the body that require oxygen to respire which is essential for the cells to stay alive. Therefore the red blood... | [
"Surely you are correct. When bleeding the cardiac output decreases due to decrease preload (total circulating blood volume). To compensate, the heart beats faster and squeezes harder (because cardiac output = heart rate x stroke volume). So the heart rate will increase. I am not sure if there are studies that prov... |
[
"What's up with the climate? Why is it so warm this year in Europe? Is it global warming that this years summer was crazy hot and long and winter is nowhere to be seen?"
] | [
false
] | I live in Poland. I looked at the thermometer and its showing 14C degrees at noon. Usually it was around 0, well below 0 or about 5 at most this time of year. Is this anomaly or new trend? No snow, no cold... Few years ago there was Winter that lasted half a year (a bit unusual but still much more normal) and now weather is probably beating warmness records Wtf? | [
"Certainly some of it is climate change, but not all. Some of this winter's warmth is due to ",
"El Nino",
", and some is due to the ",
"Arctic Oscillation",
". So even if there was no climate change, this would be an unusually warm winter. ",
"But all the other effects are on top of, and interacting w... | [
"Global temperatures can vary quite a bit year to year especially when comparing it to the lifetime of the Earth. It is hard to say over such a short time frame if the cause of this would be something like global warming, and the effects of it would take place in a much longer time frame than over the course of one... | [
"That explains a bit. Thanks!"
] |
[
"Does sighing actually relieve stress?"
] | [
false
] | We all sigh in tense situations, or after a long, tough day, but does it actually do anything biologically to soothe you or calm you down? | [
"Many people do not consciously breathe or relax during the day, while they're engaged with other things, and the sigh may be a time when for the first time that day you decide to take a full breath and relax your muscles (shoulders tend to be the worst offenders here, if you're holding them up higher than they res... | [
"Semi-related...I'm fairly certain that swearing and yelling when you hurt yourself (like stubbing your toe) actually helps you deal with the pain.",
"Definitely reason why we do it. Taking deep breaths increases your Blood-Oxygen level too, I believe."
] | [
"Have there been any studies done on it? What would be the relationship between the swearing and the pain in the brain? Just mild distraction maybe?"
] |
[
"Is there an index which identifies the most habitable geographies?"
] | [
false
] | Out of all of the livable geographies on Earth, I expect some should be more condusive to civilisation. Whether it is easier access to more natural resources, more fertile land, temperate climate, less geologically active, less chance of flooding or drought, or easier access by land, it's clear that a lot of factors are at play. Is there an index to rank the most habitable places for humans, or an index to estimate the human carrying capacity of a land area? | [
"The USDA had made a \"Natural Amenities Index\" if that helps. It's not exactly what you're after but I would say it's adjacent. ",
"https://www.ers.usda.gov/data-products/natural-amenities-scale/",
"Granted this is just for the US, but it may give you a useful jumping off point for the rest of the world."
] | [
"That sounds similar to what I'm after. I was picturing the globe and trying to decide whether there is a numerical way to quantify a 'best place and worst place for us to inhabit'. I was actually about to submit it as an economics question rather than Earth Science.",
"The ERS (Economic Research Service) says th... | [
"Actually it's not flat topography, the varied topography, i.e. mountains. ",
"This link gives a summery of the preferences ",
"https://www.ers.usda.gov/data-products/natural-amenities-scale/documentation/",
"And there is a link there to the complete study. I would imagine it explains the methodology and sele... |
[
"Is it possible to experiment with new drugs via computer simulation/programs?"
] | [
false
] | Do people already do it? How is it significant? Which programs are used? | [
"We routinely test drugs with computer modelling.",
"http://www.sciencedaily.com/releases/2012/06/120611133759.htm",
"Here's one."
] | [
"That is one of the applications of ",
"Folding@Home",
". It's a distributed computing project using idle computers & PS3s to run protein folding simulations/computations. ",
"Improperly folded proteins cause a number of diseases, including Parkinson's and Alzheimer's. But computational modeling of how a prot... | [
"If protein folding simulations are used for things like drugs and diseases, wouldn't the government be funding this stuff with enough money to build super computers? Or is it just not as important as the other stuff they're funding with our taxes?",
"Anyways, how many modern day $400 gaming PCs would it take to ... |
[
"Is it mathematically significant for sets of consecutive numbers to add up to a prime number or does it happen often enough that nobody cares?"
] | [
false
] | null | [
"The sum if consecutive numbers from a to b is (b - a + 1) * (a + b) / 2. The only ways that works out to be prime is if:",
"If a + b = 2, then you are looking at a = 0, b = 2, 0 + 1 + 2 = 3.",
"If b - a + 1 = 2, then b = a + 1 and a + b is prime. But a + b = a + a + 1 = 2 * a + 1, so for every odd prime p = 2k... | [
"You can split into cases and apply the previous result with slight modification. If b is negative, it's exactly the same with negative signs (we'll allow negative integers to be prime here). So let b be positive. If b is greater than a in absolute value, then we can reduce to the case of adding from -a + 1 (recall... | [
"Then you get four additional cases. Setting c = -a, so that c is positive, you have:",
"The first case yields sum from -c through c+2, which works because the part from -c to +c just cancels itself out.",
"The second case gives you b + c = 1, which doesn't yield any solutions.",
"The third case gives you the... |
[
"Does the universe rotate?"
] | [
false
] | I was thinking about the evolution of our models of the universe from geocentric to heliocentric etc. and how as they expand out everything is rotating. Earth, the sun, the galaxy, etc. Does the universe as a whole rotate? If so, how is it measured? If not, what are the theories as to why not? Could it be because of the jump from 3 dimensional bodies to a 4 dimensional object as in the reference to the expanding universe being the material of an inflating balloon (not the air)? | [
"Modern astrophysics suggests that our universe is not rotating. Only inflating at an ever accelerating rate. It's relatively homogeneous and isotropic. This is thought to be caused by a scalar field which contained an extremely unstable particle known as the Inflaton. This is thought have triggered extreme expansi... | [
"Question: can a plane of infinite size meaningfully rotate? "
] | [
"Question: can a plane of infinite size meaningfully rotate? "
] |
[
"What if somebody DESCENDS into a dive too quickly?"
] | [
false
] | Everyone knows that ascending from a dive can cause decompression sickness; "the bends". But what about DESCENDING too quickly? Obviously, there may be damage to the ear-drums, but otherwise, this doesn't seem to be something people talk about. I don't really have much to go on.. Thinking purely from a non-professional standpoint, I could imagine that theoretically, one could dive so fast that the pressure causes compression of water vapor in the lungs, causing condensation faster than the body can absorb the water, and therefore could cause very sudden death... or in the case of humid air being administered to the diver on decent, pneumonia. Still, this may require a dive that is physically impossibly fast and deep. I don't know though. | [
"I'm a certified scuba diver, and the biggest problems with descending too quickly are, as you mentioned, ear squeeze, and mask squeeze.",
"Ear squeeze occurs when the pressure outside your ear is much higher than the pressure inside your ear. If you descend too quickly, and don't equalize the pressure, there can... | [
"The last thing you said about the lungs being its own system only applies if you assume you're scuba diving with a tank though, correct? It would be different if you were free diving."
] | [
"Oh. I didn't even think about it like that!\nIf you were free diving, as long as you kept your airways shut, the only pressure exerted on the lungs would be that of the outside water on the body as a whole. The lungs are protected by the ribs, though, too.",
"You would be screwed long before you got to the point... |
[
"My idea for an AskScience logo."
] | [
false
] | (also a couple of other versions in edits below) Someone with better design-fu could do a better one (particularly the arm, I don't like the arm but I couldn't make it look good), but seeing as that equation is the answer to many a question asked here, I think it would be nice if it was in the logo. People have rightly pointed out that this is more of a physics logo than a science one, so I invite all you non-physicists to stick something on this and (if possible) we could rotate through? Or, if that's not going to happen, how about a ? | [
"Rather than the tried and true chalk board, it might look good if we show a gradual increase in scale from left to right. Maybe start with an atom, then to the right have a pretty universally recognized compound like water, then a small DNA double Helix, an animal, a mountain, Earth, and then the Milky Way.",
"M... | [
"True, but to the layperson asking the standard \"if E=mc",
" then how can a photon have energy?\" question, the version I used is probably clearer. We don't often get questions that require answers advanced enough to use 4 vectors. "
] | [
"What about just trying to send up representatives of each field. 6 aliens. A physicist in purple, a biologist in blue, chemist in green, astronomer in yellow, social??? in orange (maybe a clipboard to represent??? or a \"psychologist\"), a doctor in grey, and an engineer in red (many of the red shirts I've seen he... |
[
"What exactly regenerates in a person during a coma?"
] | [
false
] | Hello I heard stories of people waking up from a coma after years at a time, and I was wondering, what is it in their bodies that regenerates during that time? Also, how come the body developed the means to regenerate from injuries that take years of being in a coma to regenerate from, considering that in the wilderness it would have a zero chance of survival while being in a coma for a days, let alone a few years. Thanks! | [
"There are so many different causes of coma that there isn't a single answer to your question. Some are quite easy to reverse, for example hypoglycaemia (low blood sugar) whereas others are slightly more tricky due to the physiological sequelae of the injury or treatment (e.g. cerebral hypoxia).",
"Generally peop... | [
"Anecdotal: When the cause is medical, it seems like people are pretty sleepy coming out of it. I haven't really ever seen anyone come back from a traumatic coma, so I could not comment on that. If a person is placed into a coma for medical reasons (surgery, intractable seizures), it depends on the agent used to pu... | [
"Do people feel sleepy or wide awake after a coma?"
] |
[
"Do other mammals other than humans also experience sleep issues such as insomnia or having difficulty to fall or stay asleep?"
] | [
false
] | null | [
"That's a really good question!",
"/u/CatalyticDragon",
" answered this question a couple of weeks ago in ",
"this thread",
"Well insomnia, or just sleeplessness, may have many differing causes. It could be the result of various medical (physical, psychological) or environmental factors. So the short answer... | [
"thank you!"
] | [
"No prob! Thanks for the gold!"
] |
[
"Is it possible to have groups G and H such that G is a subgroup of H and H is a subgroup of G?"
] | [
false
] | obviously I mean when H and G are not isomorphic, otherwise the integers would work. | [
"Yes, it is possible!",
"For example, take free groups on 2 and 4 generators F2 and F4. Obviously F2 is a subgroup of F4. They are not isomorphic -- for example, they have different amount of homomorphisms to Z/2Z. As for injection of F4 into F2, here is one example:",
"\na -> x;",
"\nb -> yxy^-1;",
"\nc ->... | [
"That is what I meant. Thank you for answering what I meant rather than what I said."
] | [
"In the context of mathematics, a \"group\" means a set of elements, and an operation on those elements that satisfies certain properties. One example of a \"group\" is that the elements are the integers (whole numbers), and the operation is addition. Another example of a \"group\" is that the elements are permutat... |
[
"How does the demon core work?"
] | [
false
] | I read the wiki, but I am still confused. Something about blocking neutrinos? Maybe explain it on an 8th grade level if you can? Thanks! | [
"Fission occurs by breaking big nuclei with neutrons (not neutrinos).",
"If you have a bunch of material that can fission, the amount of neutrons being produced and the amount being lost (without fissioning) determines the k value.",
"If k>1 the mass is called super critical (accelerating reaction). k=1 it is c... | [
"The main idea at play here is critical mass (",
"wiki",
"). An older post of mine on this:",
"There's two key ideas at work here. The first is the neutron population. This can be thought of as the amount of neutrons you had before, minus the amount that escaped, plus the amount that were created. If the ... | [
"The \"core\" is just a chunk of plutonium metal, in a specific size and shape.",
"Plutonium atoms are radioactive. This means they are liable to fall apart and send out a spray of high-energy particles. This split usually happens spontaneously, at random. But it can also be made to happen immediately, if the ato... |
[
"Does gravity really vary between major cities/points on earth?"
] | [
false
] | null | [
"Here's a picture"
] | [
"Well the force goes as 1/r",
" but the mass goes as r",
" Mountains are pretty heavy and there's more Earth near the equator."
] | [
"Well the force goes as 1/r",
" but the mass goes as r",
" Mountains are pretty heavy and there's more Earth near the equator."
] |
[
"In a WiFi network, are the participants able to directly communicate with one another or does all traffic go through the router first?"
] | [
false
] | [deleted] | [
"In 802,11, yes various devices may communicate directly. However, sometimes they cannot hear each other and communication must be relayed through an access point. (E.g. suppose we're on opposite sides of the access point, each in range of it but out of range of each other.)",
"In basic 802.11, the access point... | [
"The much more common system that is utilized by nearly all networks is the client-server model ",
"This terminology is wrong. A wireless network that has all traffic traversing the access point is called \"Infrastructure\" mode. A network where all peers communicate directly is an \"Ad-Hoc\" network. "
] | [
"Couldn't the client-server model still apply to an ad-hoc or peer-to-peer wireless network? For example: a music player and a controller where the controller actively broadcasts commands or requests for stream metrics while the music player takes the commands and requests and either executes the commands or serves... |
[
"What elements are red dwarf stars made of at the end of their life cycle?"
] | [
false
] | Are red dwarf stars capable of fusing helium into heavier elements such as carbon and oxygen before being compressed into white dwarfs, or are they comprised solely of hydrogen and helium when they enter white dwarf stage? I know that's a fairly close-ended question, so if you have any other cool facts about red dwarfs (or stars in general) feel free to share! | [
"It depends on their mass. M stars, what we usually mean by red dwarves, range from about 0.08 solar masses to 0.5 solar masses. Below 0.3 solar masses, they become fully convective, which means that all the material in the star is cycled through the core eventually. So, we can split their final composition at t... | [
"The core continues to contract after shell ignition, since it still has no energy source of its own. This raises the pressure and temperature in the shell, since it contracts too (and it receives a lot of the gravitational heat from the core as well). But if you just stopped the core collapsing once the shell ig... | [
"Inspired by your comment (\"a red giant phase ...is not a helium-burning phase\"), I looked at ",
"Wikipedia",
". It says:",
"When the star exhausts the hydrogen fuel in its core, nuclear reactions in the core stop, so the core begins to contract due to its gravity. This heats a shell just outside the core,... |
[
"Do wild animals ever tear an ACL or pull a hamstring?"
] | [
false
] | These and similar injuries occur regularly when humans try to run as fast as they can or twist their joints in the wrong ways. Do wild animals have these injuries and are they just never shown in wildlife shows or do they have ways to avoid them alltogether? In case of the latter, how? | [
"I'm assuming that you're talking about something like a deer or a lion or what not. Going forward with this interpretation.",
"Let's take the horse as an example. ",
"Equine stifle injury",
" is a \"knee-like\" injury for a horse that is related to several ligaments, so we can sort of expound that this is ... | [
"To answer a different part of that question, humans have a skeletal/muscular system still adapting from quadrupeds, and we are more likely to succumb to specific problems"
] | [
"Usually a predator that can't hunt dies. Same for herbivores that can't flee. You don't see them for the same reason that you don't see many dead pigeons."
] |
[
"How does phone charging port moisture detection work?"
] | [
false
] | I usually play with my phone while in the shower and often the moisture detected notification pops up on my samsung note 8. I looked online but the only results are people trying to get rid of the notification whereas I'm interested in what sort of sensor or system they use to determine that the charging port is indeed moist. | [
"The \"charging port\" is actually a USB(-C) port. The pins on these carry data, but a voltage can also be present on one of the pins. ",
"When a liquid (or otherwise conductive object) bridges two or more pins, an USB controller can detect when a short-circuit happens, and warn for this.",
"Source: ",
"A pat... | [
"Is it the same concept for micro USB ports? I sometimes got the moisture warning despite my phone not being near anything possibly damp."
] | [
"It depends on the implementation, but electrically it doesn't really matter what kind of connector is used. As long as the pins can be bridged by something and the controller can detect a short, it can happen."
] |
[
"Why do heavier/fatter(no offense) people seem to have better singing voices?"
] | [
false
] | [deleted] | [
"Opera singer here--take fat out of the equation. That's just a tired old stereotype. Instead, use the concept of size. Big voices do tend to come in big packages, and there's a physiological reason for that. The vocal cords themselves dont make much noise on their own. Instead the larynx is used to amplify ... | [
"They don't. The \"Fat Lady\" stereotype for opera singers is just that - a stereotype. When the average person thinks of an opera singer, they typically think of performers of the Wagnerian tradition, and especially of Wagner's \"Ring Cycle\" (think viking horns and valkyries). This stereotype has likely been expa... | [
"Confirmation bias",
" . The biological functions that create fat are not related to the biological structure of vocal chords."
] |
[
"Hey /r/askscience I've had this \"rock\" almost all of my life I've always wondered what it is"
] | [
false
] | So I found this "rock" in my front yard a LONG time ago and I've always wondered what it is. It's heavy, appears to be metal, very lustrous. I took it to my middle school geology teacher a long time ago and she couldn't identify it but she thought it could be a meteorite. anyone know what this is? or can direct me to a proper rock scientist?(So I found this "rock" in my front yard a LONG time ago and I've always wondered what it is. It's heavy, appears to be metal, very lustrous. I took it to my middle school geology teacher a long time ago and she couldn't identify it. but she thought it could be a meteorite. anyone know what this is? or can direct me to a proper rock scientist?) Images : I'll try and figure out it's density but I need access to the lab at my school | [
"Looks kinda like ",
"pyrite",
" to me."
] | [
"Geologist here.",
"Does it appear to fracture into little cubes? If so then it's probably galena (Lead Sulfide).",
"http://en.wikipedia.org/wiki/Galena",
"A rule of thumb: If you think it might be a meteorite, it's not a meteorite. This holds true 99.99999% of the time. You have no idea how many people bring... | [
"Mining engineer here with some geology background. This looks similar to the type of rocks found in a lead-zinc-silver mine that a colleague of mine previously worked at. Based off your images I would suspect it is galena, maybe sphalerite. Hoping a geologist can provide more insight.",
"\nGalena: ",
"http://m... |
[
"What exactly do red blood cells contain?"
] | [
false
] | So RBCs (erythrocytes?) contain no nucleus, DNA, or mitochondria, but hold lots of haemoglobin. Is that all? Are their plasma membranes unique in any way? | [
"They contain a number of enzymes and other proteins. For example, RBCs have glucose transporters in the membrane and a complete enzyme cascade for glycolysis. This is how they generate a little ATP (from glucose) to fuel cytoskeleton remodeling, lipid biosynthethesis, flippases (which maintain lipid asymmetry acro... | [
"Their shape maximizes their surface area : volume ratio, to facilitate gas and other stuff exchange. I don't recall the specifics of their membrane uniqueness beyond obvious markers or stabilizing proteins, but I do remember reading something a while back about how they contain cytoskeletal remodeling machinery, t... | [
"There are erythrocyte specific markers in case you are interested. Specifically CD71 is present on erythrocyte precursors to make sure the cells get adequate iron via the transferrin receptor. The iron being required to synthesize Haemoglobin.",
"By the time they mature though the signal is basically gone. In mo... |
[
"I had heard that men and women handle body heat differently as an evolutionary byproduct. Women tend to radiate heat more to keep young warm, and men tend to retain heat more to endure longer periods of hunting and foraging. Is there any truth to this claim?"
] | [
false
] | null | [
"It doesn't make much sense as stated, since retaining heat while hunting and foraging is likely to be harmful except in cold environments. A hunter in the tropics (where early humans lived) would need to radiate heat efficiently to avoid heatstroke."
] | [
"As atomfullerene stated, it doesn't make any sense.",
"It seems like you are basing it off of cold weather, but we evolved primarily in African savannahs where it is pretty hot.",
"In fact, we have evolved to be incredible heat dissipators. Our sweat glands are fairly unique. Chimps have a few primitive sweat ... | [
"Please review our posting guidelines in the sidebar, thanks."
] |
[
"At what point do foreign words from one language become officially adopted into another language?"
] | [
false
] | It's very common for languages to adopt words from other languages, but at what point does it become official? For example, the German word schadenfreude, is used so much in English now, at what point would the English language officially adopt it as an English word with German roots, if ever? Edit: Formatting | [
"It's never official in the literal sense, since the use of ",
" ",
" isn't dictated by any organization that's formally \"in charge.\" Probably the closest thing to official is getting dictionary publishers to recognize the word."
] | [
"This is true for English, but French, for example, is governed by the Académie Française."
] | [
"At least in the case of Spanish, a word is only official when it is accepted by the Spanish Royal Academy. This may be quite formal but they do keep up with the evolving language and even track regional variations across different countries.",
"Italy has the Accademia della Crusca but it's a bit less reputable."... |
[
"Who can help me with acoustic wave propagation in membranes?"
] | [
false
] | I'm doing some research on acoustic sensors. I've seen experimentally that, with no tension, the waves in a polymer membrane damp out within a few wavelengths. Upon application of tension to the membrane, the waves travel much further. Intuitively, this makes sense to me, but I can't find any math or explanations to back this up. Can someone give me an explanation for this, or direct me to some good resources? | [
"I'll take a stab: the wave under consideration has two separate components, the compressional part that is the physical sound wave, and the transverse part that is the shear stress. By increasing the tension across the surface, we reduce the transverse component (because the membrane is less flexible) and so incre... | [
"Thanks! This makes sense now that I think of it. But not when I apply it to my application. ",
"I'm dealing with Lamb waves. There are two modes, symmetric (compressional) and anti-symmetric (shear). My experiments seem to suggest that the mode I'm working with is the shear mode, though I haven't verified this 1... | [
"I'm in no way an expert, I've only done some very formal things with a 2D wave. I'll check some of my old note to see if I even considered tension across the surface. Maybe it is the transverse wave that propagates further because the tension forces more of the energy into the parallel component by its restriction... |
[
"Has new life ever appeared on Earth since the first life arose 3.7B years ago?"
] | [
false
] | [deleted] | [
"We don't know what the life looked like 3.8 billion years ago or if it stuck around. All we know is that there was indeed life back then. This life could have died out at 3.75 billion years ago and new life began at 3.74 billion years ago. This however is incredibly unlikely. We assume that it only started once be... | [
"Consider how difficult it will be to find 'new' life. The 'new' life is competing against life forms that have had billions of years to fit into their niche, and has to survive long enough and reproduce prolifically enough that we notice it."
] | [
"Very unlikely for one simple reason: old life is already here to eat any would-have-been new life's raw materials."
] |
[
"Is it possible to reverse engineer the DNA sequence which encodes a protein given the amino acid sequence of that protein?"
] | [
false
] | Would it be possible to do this without any context from the source organism's genome? | [
"Yes. When we have a protein sequence and we want to find where within the genome that it is encoded, we make a mixture of all possible codon sequences that would make that protein and use that mixture as a PCR probe. The technique is called a ",
"degenerate primer",
" probe. ",
"Edit: ",
" a PBLAST is a ... | [
"Methionine and Tryptophan only have one functional codon, and most of the others only have two codons which differ by only one base. So, given a protein with right constituent sequence of amino acids, it should be possible to get pretty close. You could definitely narrow the \"original\" sequence down to a small s... | [
"Well, If you had the DNA sequence of, say, the human gene, and you wanted to take a guess at the sequence of the chimpanzee gene, you could probably do a pretty good job. We know that humans and chimps have very few differences in even their DNA sequence.",
"To be clear, are you asking a theoretical or a practic... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.