Wikipedia:Reference desk/Archives/Science/2011 July 14

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July 14

Toilets

I was recently in Hanover, beautiful place btw, if you ever have the chance, but nevermind that, anyway, the private toilets are different. They have a kind of "platform" in the bowl that the, erm, solid releases, fall o, which does not have water, then there is a lower area in the back that the flush pushes it into that has water. Here in the states by contast the releases drop directly into the water, like a true bowl. The US toilets have the problem of excessive and uncomfortable splashing, but the German toilets have the problem of the odor of faeces not submerged. Is there a middle ground that solves the splashing problem without creating the odor problem? Thanks. 12.177.253.250 (talk) 00:19, 14 July 2011 (UTC)

There seem to be a wide variety of alternatives listed at Flush toilet#Bowl design, but it's hard to tell which have the best splashing versus odor trade off by looking at them. You might want to ask on a plumbing forum such as this one. 99.24.223.58 (talk) 00:48, 14 July 2011 (UTC)

Modern dual flush toilets from Australia would seem a sensible middle ground. Your personal output is quickly drowned, but much less water is consumed than in a typical American toilet. And less splashing. As an Australian visiting America it made me feel comfortably at home to find them at Grand Canyon Village, a town with water supply challenges. HiLo48 (talk) 06:56, 14 July 2011 (UTC)

Original research, but the low seat versions seem to be the best, as the drop is only a couple of inches. It just slides into the water rather than dropping. Also see Wikipedia:Reference_desk/Archives/Science/2009_March_16#German_toilet for more information on the German attitude.--Shantavira|^{feed me} 07:55, 14 July 2011 (UTC)

I came across this toilet design in Poland at my aunties house. After the 1st time I used it and made a mess I learned to lay a piece of toilet paper down 1st which greatly reduces the chance you'll need to clean up after. Vespine (talk) 23:16, 14 July 2011 (UTC)

German toilet currently redirects to the stub washout toilet (which is considerably smaller than the flush toilet#Washout toilet section). From reading elsewhere, I've understood that the primary motivation behind this design is to allow easier examination of the stool for hygienic and health purposes, a cultural practice. -- 203.82.93.119 (talk) 02:21, 15 July 2011 (UTC)

Neutrino

What's the mass of a neutrino? --134.10.113.106 (talk) 01:28, 14 July 2011 (UTC)

Read the article with the surprising title of neutrino which will answer your question, especially the section with the hard to understand title of "Mass". If you have any questions about what you read in that section, feel free to come back and ask them. --Jayron32 01:39, 14 July 2011 (UTC)

Or to put it in a less blunt way, we're volunteer human beings here, some of us quite busy with real lives. While I love answering questions for the curious, I don't like answering questions which would be easily answered by typing the word you're curious about into the Wikipedia search bar. I suggest you read neutrino; the answer may surprise you.-RunningOnBrains^(talk) 03:32, 14 July 2011 (UTC)

Please see Neutrino#Mass. 99.24.223.58 (talk) 04:59, 14 July 2011 (UTC)

It gives "masses" as eV, which aren't mass. --134.10.113.106 (talk) 06:54, 14 July 2011 (UTC)

Electronvolt#Mass suggests otherwise. Can someone confirm that 1 eV is 1.78*10^-33 grams? 99.24.223.58 (talk) 07:14, 14 July 2011 (UTC)

Strictly speaking an eV is a unit of energy, not mass. However, (as the eV article states) the mass-energy equivalence principle makes it equivalent to 1.78266173 * 10-33 grams [1]. -- CS Miller (talk) 08:38, 14 July 2011 (UTC)

Just in case this needs clarification, as the Electronvolt article states, in natural units where c=1, eV is a unit of mass (as well as momentum, energy, etc.). Alternatively, sometimes people write eV/c^2. 80.187.151.104 (talk) 05:56, 17 July 2011 (UTC)

Breaking molecules

When you cut a piece of plastic, are you actually cutting through molecules, or just separating molecules from one another? What about other material such as wood? When water is smashed about like in a blender or a huge wave crashing, is there enough energy to break any water molecules apart? — Preceding unsigned comment added by 86.186.8.147 (talk) 02:29, 14 July 2011 (UTC)

You are seperating molecules from each other, not breaking intramolecular bonds. In general, intermolecular bonding is relatively weak, which is why you can seperate molecules from each other fairly easily. In substances which are not composed of discrete molecules, but rather consist of a massive network of nearly identical bonds, like titanium or sodium chloride or diamond, the material is actually quite hard to break. But for substances composed of molecules, it is usually fairly easy to seperate the molecules from each other, comparitively speaking. --Jayron32 02:32, 14 July 2011 (UTC)

Plastics vary by polymer length. If you cut some plastics with a power saw, they will ionize (you can often smell ionized plastics which smell like burnt plastic.) The same is true of wood, except that ionized wood smells more like burnt wood than burnt plastic. Water can not be ionized in a blender. Nor will ocean waves spontaneously ionize. 99.24.223.58 (talk) 04:51, 14 July 2011 (UTC)

Whether you are breaking molecules or not depends on molecule size. Water has very small molecules, so there is almost no way to break them apart by physical means (chemical or electrical means are all that can do it). With plastics, if the polymer is long enough, you will actually be breaking molecules apart (wood is made of cellulose, but I don't think the individual molecules are quite as long). --T H F S W (T · C · E) 17:28, 14 July 2011 (UTC)

The comments about the smell when cutting plastic and wood are probably wrong. Cutting plastic or wood with a power tool produces a lot of heat via friction. It's more likely that you smell burning plastic because you are actually burning the plastic.--Srleffler (talk) 16:31, 16 July 2011 (UTC)

Oppositional defiant disorder - Political abuse of psychiatry?

So a child's parents tell them to follow religious teachings, and the freethinking child disobeys parents, smoke pots and have sex, will they be diagnosed with Oppositional defiant disorder? Or all anarchists (including Noam Chomsky LOL), according to APA, are suffering from ODD? [2][3] Why APA is abusing psychiatry in Soviet-style? --111Engo (talk) 03:30, 14 July 2011 (UTC)

On a further research, I found this discussion. See the last post by Bruce A. Now I'm confused. Is it associated with children only, and the media misrepresenting the manual? --111Engo (talk) 03:39, 14 July 2011 (UTC)

Is this a question? Are we allowed to give more than one answer? AndyTheGrump (talk) 03:41, 14 July 2011 (UTC)

Well, you really shouldn't put much weight in Yahoo answers, and the manual in question certainly does not seem to support the claims made by the article to which you linked. In all instances they are (implicitly) describing children or adolescents being oppositional or defiant toward adults, and a person must meet at least four of the criteria, only two of which have to do with disobeying authority. They also state that the behavior must persist for "at least 6 months", and must present an "unwillingness to compromise", none of which seem to apply to civil disobedience. That is certainly not the meaning intended by the writers of this book (doctors are people too). They really should have included the phrase "routine requests", since the real manifestation of this disorder is supposed to be when a person will not comply with a simple request like "Sir, please put your pants back on. This is a family establishment." Of course, I think it's another buzzword term to excuse people for acting like assholes (read: overdiagnosis and self-diagnosis of ADHD and Aspberger's), but that's my personal (and, admittedly, only slightly educated) opinion. -RunningOnBrains^(talk) 04:00, 14 July 2011 (UTC)

I would indeed take such psychiatric practices with a huge grain of salt. It is not like the industry has a spotless track record! The criteria require that children who vehemently disagree with rules might be angry in two identifiable ways - which should scarcely seem a surprise under the circumstances. Psychiatry is a matter of people having problems and someone trying to fix them - where "having problems" means that someone doesn't act the way the person in a position to pay the bills wants. Wnt (talk) 04:37, 14 July 2011 (UTC)

To confront the "hidden question" in the OP's post, with many behavioral disorders, there is a modern trend towards overdiagnosis and medicalization. This does not mean that the disorder itself is not real, just that everyone who claims to have the disorder, or who are assigned the disorder by a medical professional, may not in fact have it. In other words, there are real people with real problems that may need real help. However, this is complicated by the fact that personality traits which are considered outside of the normally acceptable pallate of personality traits have themselves been confused with genuine behavioral disorders, and thus people, even well trained medical professionals, confuse when someone has a genuine need for medical intervention, versus where someone is just differently wired, but not in a manner which interfers with normal life. At one time, mental disorders which were treated medically were limited to serious psychoses like schizophrenia, but over recent history there has been a trend to treat what used to be considered as normal (if somewhat annoying in certain social situations) personality traits as disorders. --Jayron32 04:40, 14 July 2011 (UTC)

Hmmmm... how about female hysteria? According to the article it affected 25% of women, including symptoms like "irritability, loss of appetite for food or sex, and 'a tendency to cause trouble'". Sounds like a rather closely related condition, no? Wnt (talk) 04:52, 14 July 2011 (UTC)

That's sort of the point. There may have been real women with real psychological problems that needed real theraputic or medical intervention. But by overdiagnosing such a rediculous number of women, with perfectly normal personalities, as "hysterical", it both wasted the resources of the medical system and masked the real problems of the few real women who may have needed real help. A third problem is a sort of "backlash" against people who really have mental disorders, since the public has become quite aware of overmedicalization. For example, some kids really do have ADHD. But so many kids that don't have it are mistakenly diagnosed with it that people believe that the disorder doesn't really exist, and that the label is just an excuse for parents to drug their children and keep them compliant. The kids that really do need drugs to manage their disorder thus get stygmatized as "not having a real disorder" when they actually do, because all of the kids that actually don't have it give everyone else a bad name. Again, I am not in full agreement with the OP here, in the sense that I recognize that behavioral disorders of all types do exist, but the tendency to make every socially inconvenient personality trait one of these disorders does a disservice to literally everyone involved. To the OP's point, there really are people who have a mental disorder that makes them violent and unmanagable in the face of authority, to the point where they need genuine theraputic and/or medical help. That we confuse these people with genuine mental problems, with other people who have healthy brains but choose to be nonconformists, is the real problem. Its not the non-existance of the disorders, its the overassigning of the disorder to people that don't have it, that is the problem. --Jayron32 05:05, 14 July 2011 (UTC)

Do you mean: 1. behavioral disorders of all types that actually exist do exist, 2. behavioral disorders of all types ever thought to exist do exist, or 3. behavioral disorders of all types currently thought to exist do exist? (Excuse me if this question seems confrontational, I'm probably exhibiting challenging behaviour.)  Card Zero  (talk) 09:28, 15 July 2011 (UTC)

Are you asking whether it will be easy for religious parents to find psychologists predisposed to their opinions in order to lock up or drug children who don't believe their superstitions? Or suggesting that we must all ask our local psychological licensing authorities how they would protect against such a situation? Or are you a victim of vindictive religious parents who have tried to have you locked up or drugged? Or are you a religious parent seeking to lock up or drug a freethinking child? Context is important here. 99.24.223.58 (talk) 04:58, 14 July 2011 (UTC)

Yeah, context is important ... it's important so some holier-than-thou people of a non-religious sort can lecture the questioners and answerers about the "unethical" and contrapolicy nature of "giving medical advice". Wnt (talk) 05:15, 14 July 2011 (UTC)

The direct answer to the OP's question is that this diagnosis is only applied to children, so describing it as a Soviet-style abuse of psychiatry is off the mark. Looie496 (talk) 05:14, 14 July 2011 (UTC)

Similarly, the governmental system in Cuba in the 1960s wasn't Soviet-style, because it only applied to Cubans.  Card Zero  (talk) 09:19, 15 July 2011 (UTC)

If you have ever met an ODD child or known people that work with them regularly, you immediately know the difference between a child that has a behavior problem and one with a conduct disorder. ODD is a true mental disorder, meaning it is not rational or in many cases controllable. An ODD child could be told not to do something they don't even WANT to do, but they would do it just because they are told not to. They are some of the more sadistic people you'll ever meet, they will do things just to be contrary or as annoying as possible. ODD is a conduct disorder with all that implies, including being a potential pre-requisite to a diagnosis as an adult of antisocial personality disorder, also called Sociopathy. There's a big difference between a poorly behaved child and a potential sociopath-in-the-making. HominidMachinae (talk) 08:32, 14 July 2011 (UTC)

Severe weather warning beeps on radio

The local radio stations in Salina, Kansas owned by Morris Communications ([4]) will sometimes, when there is a severe thunderstorm warning or tornado watch/warning affecting their listening area but when they are not in continuous severe weather coverage, turn on some system that inserts a particular beeping sound once every couple minutes (more than just a simple beep...I believe the best way to describe it is a set three higher beeps followed immediately by three slightly lower beeps lasting about one second total, repeated after a little less than one second for a total duration of about three seconds). While touring the radio stations' facilities a few years ago I caught a glimpse of the hardware used to insert these beeps into the broadcast audio (fittingly labeled "SEVERE WX BEEP GENERATOR"). I went looking for information on such equipment today, but I can't seem to find anything about them using Google, despite the fact that I'm fairly certain other radio stations use variations of them (with different sounding/patterns of beeps) as well. What exactly are these severe weather beep generators and where can I find information on them? Ks0stm ^(T•C•G) 05:15, 14 July 2011 (UTC)

I believe that the article Emergency Alert System will answer many of your questions. It even has pictures of some of the equipment used, which may be exactly what you are looking for. I also see bluelinks to more specific articles on the equipment. --Jayron32 05:28, 14 July 2011 (UTC)

Actually, it wasn't EAS related...this is some system that they manually turn on when there are the severe weather alerts I mentioned in effect for their listening area and that remains on, producing the beeps, until the severe weather alert has expired or been cancelled, at which time they switch it off. The only EAS broadcasting that these stations do are EAS weekly/monthly tests. Ks0stm ^(T•C•G) 05:34, 14 July 2011 (UTC)

Ah. In that case, you seem to be looking for some sort of tone generator or Signal generator. There are hundreds of these things out there. The section titled "Pitch generators and audio generators" has a little bit on them, but not on any specific models. --Jayron32 05:40, 14 July 2011 (UTC)

Planck unit for luminosity

Does a Planck unit exist for luminosity and if so, what is it in terms of candelas? Widener (talk) 07:24, 14 July 2011 (UTC) Oh and if it happens to be a derived Planck unit, I would also like to know what it is expressed in terms of the fundamental Planck units. Widener (talk) 07:42, 14 July 2011 (UTC)

Planck power, but I can't convert because candelas are apparent luminosity instead of bolometric. 99.24.223.58 (talk) 07:47, 14 July 2011 (UTC)

Exactly right. luminosity really isn't a physical quantity and candelas really aren't a physical unit so a Planck unit for them is meaningless. Dauto (talk) 13:46, 14 July 2011 (UTC)

Correcting what I said above. I meant to say Luminous intensity isn't a physical quantity (That's the one measured in candelas). There is nothing wrong or un-physical about luminosity which is measured in Watts. Dauto (talk) 15:27, 14 July 2011 (UTC)

I suppose luminous intensity (apparent luminosity) is a real physical quantity based on radiation in the visible spectrum. But x Watts of white light is still x Watts. As a practical matter, for quantities that large, there is really no way to assume that much power would be measurable because it would ionize any observer or measurement apparatus. [5] has some details that might help. 99.24.223.58 (talk) 22:07, 14 July 2011 (UTC)

Luminous intensity depends on the physiological response of the human eye. That means it is not a "pure" physical quantity. Dauto (talk) 00:27, 15 July 2011 (UTC)

We would have to know the shape of that response curve (for three kinds of cone spectra, maybe we can use a normal distribution to approximate) to get the ratio between uniform spectrum wattage and white light wattage. Then we would be able to answer this. Sorry, that wouldn't help either, because the integral of +1 over (0, +infinity) for a uniform spectrum is probably undefined, or if it's not it should be in this case. Thank you. 99.24.223.58 (talk) 22:29, 15 July 2011 (UTC)

See Luminosity function for the shape of the response curve.--Srleffler (talk) 16:42, 16 July 2011 (UTC)

Question about animal blood analysis .

Italic text I want to know what are the normal medical values for a hematology tests

in dogs. Thank you in advance . 95.107.197.63 (talk) 09:09, 14 July 2011 (UTC)

Does this website help? canine bloodwork Zzubnik (talk) 10:42, 14 July 2011 (UTC)

Exotic matter

Is it possible to create a liquid phase consisting entirely of protons confined in a Penning trap? If it is, and assuming that does not exist at STP, what is the pressure equivalent of the boiling point at 1 nK? Plasmic Physics (talk) 10:35, 14 July 2011 (UTC)

No, liquid implies contact, and the coulomb barrier for that compression seems to be greater than could realistically be expected to be applied from external sources. Consider the power required to simply keep two protons in contact. 99.24.223.58 (talk) 10:51, 14 July 2011 (UTC)

OK, but what about extraordinary conditions like in special types of stars, where protons are crushed together? Then again that's not really a liquid, it's more like a supersolid. Plasmic Physics (talk) 11:41, 14 July 2011 (UTC)

Neutron stars exist because they are composed of neutrons, which are neutral and thus not all that repuslive. The repulsive forces involved in condensed protonic matter may be hypothetically calculatable, but likely the result would be so huge to be meaningless. --Jayron32 11:56, 14 July 2011 (UTC)

Agreed - I think we are talking about degenerate matter here, but I don't see how that can be constructed just from protons alone. Nearest equivalent is metallic hydrogen, which, in its solid form, is a lattice of protons surrounded by a sea of unbound electrons. Gandalf61 (talk) 12:06, 14 July 2011 (UTC)

It strikes me that if you beam pure protons straight into a black hole, it nonetheless will not achieve infinite charge, because the Hawking radiation will become biased. Is it possible to calculate a maximum possible charge density for a black hole? Is that the upper limit for concentration of charge in that volume of space, regardless of the nature of the containing force? Wnt (talk) 17:28, 14 July 2011 (UTC)

Does the article Charged black hole lead you to some solutions to your problem? --Jayron32 18:02, 14 July 2011 (UTC)

(EC) You are probably right about charged black holes having a limit as to how much charge they can have. According to the cosmic censorship hypothesis, non-rotating charged black holes with r_Q > r_s/2 in the Reissner–Nordström metric, where r_Q is a radial measure proportional to the black hole's charge and r_s is the black hole's Schwarzschild radius, do not exist in nature, because that would result in a naked singularity. Red Act (talk) 18:07, 14 July 2011 (UTC)

I would have preferred a derivation based on the impossibility of shooting the particle into the field because (for example) virtual pairs would be sure to interact with it and spirit the charge away - rather than an unproved ban on singularities in free space - but it does give a ready number. The article says that

$r_{Q}^{2}={\frac {Q^{2}G}{4\pi \epsilon _{0}c^{4}}}$

and the total radius r_S in which the charge is confined is simply 2r_Q. Thus Q <= (r_S/2)(c²)sqrt(4πε₀/G) = sqrt(3.1415927 * 8.85418782×10⁻¹² F·m⁻¹ / 6.6738480×10⁻¹¹ m³ kg^-1s^-2) (299792458 m/s)² r_S /2

= sqrt (0.416794806 s⁴·A²·m^-2·kg^-1·m⁻⁴ kg¹s²) (8.98755179 × 10¹⁶ m² s^-2 r_S/2

= 2.90116587 × 10¹⁶ C/m r_S. Unless I fouled up... And I did, thanks Dauto for spotting the factor of 2 I forgot about Wnt (talk) 18:56, 14 July 2011 (UTC)

N.B. one actual unit of charge, (1 / 6.24150965(16)×10¹⁸) C, should then be confined to occupy at least rS = (1 / 2.90116587 × 10¹⁶) m/C (1 / 6.24150965(16)×10¹⁸) C = 1.38063158 × 10^-36 m or 1/11.7 of the Planck length. Odd... Wnt (talk) 19:10, 14 July 2011 (UTC)

What's odd about that? Dauto (talk) 19:44, 14 July 2011 (UTC)

Well, the Planck length is special in terms of when the Compton wavelength of a black hole just barely fits inside the Schwartzschild radius, but I haven't heard of a similar fundamental role in defining charge. If 11.7 were some simple/predictable number, it would mean the various fundamental constants described above could be defined in terms of one another - one less fundamental constant. Wnt (talk) 22:56, 14 July 2011 (UTC)

What you did was calculate $2\alpha ^{\frac {1}{2}},$ where $\alpha \,$ is the fine structure constant.

$r_{e}^{2}={\frac {e^{2}G}{4\pi \epsilon _{0}c^{4}}}=\alpha l_{P}^{2}$

Dauto (talk) 23:31, 14 July 2011 (UTC)

Ah! Thanks for setting me straight. I've fixed the factor of 2 error in the calculations above. The conclusion we reach, then, is that the smallest possible black hole contains a Planck mass and no more than the Planck charge within a Planck length. Assuming (!) that no force of nature is stronger than a black hole event horizon, then within any sphere of space of radius N Planck lengths, there can be no more than N Planck charges. Where the Planck charge happens for some bizarre reason to be about 11.706 ordinary charges. Wnt (talk) 23:46, 15 July 2011 (UTC)

How are charged black holes related to my scenario? Plasmic Physics (talk) 02:55, 15 July 2011 (UTC)

They are not, except for the fact that they are ways to pack positive charged particles. Dauto (talk) 15:04, 15 July 2011 (UTC)

I was hoping to work out the upper limit for charge concentrated in a region of space (and did) but it is absurdly high for normal purposes, except maybe over some vast distance. Wnt (talk) 23:46, 15 July 2011 (UTC)

Well, I'm not looking for the greatest number of protons that can be squeezed in a known volume, only the possibility of a liquid phase with a distinct boiling point. If there isn't such a case anywhere in the universe then that's a good answer. Plasmic Physics (talk) 00:57, 16 July 2011 (UTC)

That seems to be the answer. Dauto (talk) 13:55, 16 July 2011 (UTC)