Wikipedia:Reference desk/Archives/Science/2007 November 1

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November 1

What Are Some Things All Things On Earth Have In Common That Are Living Or Non-Living?

I wonder, what are some things all things on Earth have in common that are living or non-living? —Preceding unsigned comment added by 208.103.143.9 (talk) 03:07, 1 November 2007 (UTC)

Please clarify your question. Everything is living or non-living. — Daniel 03:15, 1 November 2007 (UTC)

They're all made up of atoms? -- MacAddct  1984 ^{(talk • contribs)} 03:19, 1 November 2007 (UTC)

Not everything is made up of atoms. Evidence_of_evolution#Evidence_from_comparative_physiology_and_biochemistry lists many things that living things mostly have in common. As for non-living things, their only binding similarity is that they aren't living. Someguy1221 03:21, 1 November 2007 (UTC)

They're all made of matter and/or energy, they're all affected by the laws of physics, and they all hate getting circus peanuts on Halloween.  ;-) -- HiEv 04:07, 1 November 2007 (UTC)

Everything came from a star. --DHeyward 13:43, 1 November 2007 (UTC)

Everything? I'd be willing to bet that there's a great deal of primordial hydrogen floating around right now. --Carnildo 23:55, 1 November 2007 (UTC)

What part of ON EARTH, didn't you get? 64.236.121.129 13:38, 2 November 2007 (UTC)

They can all be mentally separated from their surroundings and referenced by a cognitive symbol, in such a way that an observer can build a working mental model with these symbols. In other words, what is a thing? When we draw a line around a cloud, why does the line go there and, not half around the cloud and half around the sky? Because classifying the cloud as an object helps us understand an survive in the world. Being a thing is not a natural property of a part of the universe, but rather a property that we ascribe to it. Or so I believe, anyway. risk 03:58, 3 November 2007 (UTC)

The definition of life would be involved here. Nonliving things take on some of the characteristics of life. Many nonliving things can grow or reproduce, like fire, crystals, and prions. Some viruses may also be considered nonliving, despite having some characteristics of life. StuRat 16:09, 3 November 2007 (UTC)

Contradiction in mass-to-energy equivalence?

I'm new at Wikipedia editing and whatnot, so I wasn't sure where I should put this where it would be noticed:

---

The article "Antimatter Weapon" states:

Quantities measured in grams or even kilograms would be required to achieve destructive effect comparable with conventional nuclear weapons; one gram of antimatter annihilating with one gram of matter produces 180 terajoules, the equivalent of 43 kilotons of TNT.

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The article "TNT equivalent" states:

By E = mc^2, when 1 kilogram of antimatter annihilates with 1 kilogram of matter the reaction produces 1.8×10^17 J, which is equal to 42.96 Mt.

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While I could just do the basic equation (mass*c^2, and convert joules to TNT equivalence), I didn't want to make an assumption without consulting anyone else first lest I made a mathematical error or overlooked some other factor in the calculation. —Preceding unsigned comment added by 24.65.12.157 (talk) 04:44, 1 November 2007 (UTC)

1 kilogram is 1000 grams; 1 Mt (megaton) is 1000 kilotons. Is that what you are confused about, or is there something else? Dragons flight 04:48, 1 November 2007 (UTC)

Ugh. I missed the "one gram" versus "1 kilogram" part. Well, we all make mistakes. C'est la Vie. —Preceding unsigned comment added by 24.65.12.157 (talk) 04:54, 1 November 2007 (UTC)

Medical question

Deleted. William Ortiz 08:38, 1 November 2007 (UTC)

Sorry, but this page isn’t a place to ask for medical advice, either. As it says at the top of the page: "Do not request regulated professional advice. If you want to ask advice that "offline" would only be given by a member of a licensed and regulated profession (medical, legal, veterinary, etc.), do not ask it here. Any such questions may be removed. See Wikipedia:Medical disclaimer and/or Wikipedia:Legal disclaimer. Ask a doctor, dentist, veterinarian or lawyer instead." MrRedact 09:04, 1 November 2007 (UTC)

Do you know where on the internet they give medical advice? William Ortiz 09:11, 1 November 2007 (UTC)

Here, if you're careful to hide the request for medical advice by disguising it as a question of biology, anatomy or the way medical devices work. But you've given the game away now, so I doubt you'd have much luck asking the same question again (by the way, I think what you suggest (a) wouldn't work, and (b) would be a bad idea). Actually, a google search would help you find online medical advice. --Psud 10:32, 1 November 2007 (UTC)

NHS Direct is a good place to start.--Shantavira|^{feed me} 12:50, 1 November 2007 (UTC)

Big Bang

Was the Big Bang a chain reaction? Clem 09:59, 1 November 2007 (UTC)

If by "chain reaction" you mean a nuclear reaction then the answer is no, because protons and neutrons did not begin to form until about a millionth of a second after the Big Bang, and they did not begin to combine into stable nuclei until about 1 minute or so after the Big Bang - see our articles on the hadron epoch and Big Bang nucleosynthesis. Gandalf61 11:40, 1 November 2007 (UTC)

Of course not silly bro. How can there be a chain reaction with particles not yet formed? I'm talking about with whatever was formed. Did it have a chain reaction? Clem 14:05, 1 November 2007 (UTC)

There's no need to call a volunteer "silly" for answering your question as phrased -- especially when he then expands your question to give you exactly the answer you wanted. It's rather rude and quite unwarranted. Another example of what Gandalf linked is at timeline of the Big Bang, particularly the 17-minute period of nucleosynthesis which established the initial ratio of hydrogen to helium. — Lomn 14:21, 1 November 2007 (UTC)

I think most interactions that occurred immediately after the big bang--quark-gluon interactions to form nucleons and nucleons and leptons forming atoms--are not chain reactions because there are no particle emissions necessary any of these reactions - a chain reaction is a series of reactions that require as input some output from a previous reaction, so that the previous allows the next to occur and so on. So I would say the answer is no in general, but specific reactions might be catalyzed from energy or lepton release by some of these primitive interactions. SamuelRiv 14:28, 1 November 2007 (UTC)

I suppose I'm thinking more in terms of instances of interrupted stability wherein under different circumstances some changes might not occur at all or occur as rapidly except for the occurrence of previous events such that event of type "B" will cease to occur if and when event of type "A" ceases to occur. Maybe "sequence of dependent events" is more apt terminology than "chain reaction". Clem 17:09, 1 November 2007 (UTC)

Okay then, you are asking a very general question. All big-bang cosmologies that I know of come from very fundamental fluctuations in the background. A fluctuation may create a false vacuum, for example, and the cosmological effects are calculated from that state alone. So everything follows from this one single event, and yes, from there everything is dependent on what comes before. Caveat--the notion of dark energy may prove that some critical events in the universe's history are not caused by a "sequence of dependent events". SamuelRiv 02:24, 2 November 2007 (UTC)

"Superlinear"

First things first, hi desk, long time no see! Anyone have any idea what this word "superlinear" means? My first guess would be a function that increases faster than a linear function, but then you can of course have an incredibly steep linear function. A friend of mine asked me in the context of a biological function. Can someone clarify? It's not something that i've heard in my undergraduate career. Google has a load of results but none of them are very clear from what I can see. Could it be a function that is more linear than a linear function? That makes no sense to me either. Math board, maybe? :? —Preceding unsigned comment added by Capuchin (talk • contribs) 11:59, 1 November 2007 (UTC) Cheers, Capuchin 11:39, 1 November 2007 (UTC)

When describing functions, "superlinear" appears to mean a function with asymptotic growth that is more than linear i.e. it grows faster than any multiple of x (there is a different, but related, usage in "superlinear convergence"). Superlinear functions include functions such as x² or indeed any power of x greater than 1, also x^x, and functions such as xlog(x), xlog(log(x)) etc. Note that even a "steep" linear function will eventually be overtaken by a superlinear function - if f(x)=Ax and g(x)=Bx², then no matter how large you make A and how small you make B you can always find a lower limit y such that g(x) > f(x) for all x>y. Gandalf61 12:04, 1 November 2007 (UTC)

Okay thank you, that's what I had assumed. Capuchin 12:10, 1 November 2007 (UTC)

Do all the biochemical reactions happened in our body have a negative free energy?

I am a high school student. Yesterday, my teacher teacher give us a question written: Do all the biochemical reactions happened in our body have a negative free energy. Explain and support your answer. I don't know how to answer it. Any one can help. Thx in advance!!

—Preceding unsigned comment added by 202.40.139.171 (talk) 12:32, 1 November 2007 (UTC) 

Wikipedia has articles such as Gibbs free energy and enzyme kinetics, but they either do not address your question or they do not address it in plain English. This biochemistry textbook has a standard treatment of free energy in biochemical reactions for college students. If you are not ready for the math skip down to, "the free-energy change must be negative for a reaction to be spontaneous." The complication in biochemical systems is that there are many "coupled reactions" in which one chemical reaction that has a positive free energy change is "driven" by coupling it to a second chemical reaction that has a negative free energy change. Example: Two-step conversion of glyceraldehyde 3-phosphate. So the answer to "Do all the biochemical reactions happened in our body have a negative free energy?" depends on how you define "biochemical reaction". If you define "biochemical reaction" to include both of the chemical reactions in a pair of biochemically-coupled chemical reactions then yes, the combined free energy changes of the two chemical reactions are negative. If you define each of the individual coupled chemical reactions to be its own "biochemical reaction", then it is clear that some individual chemical reactions that take place in biochemical systems have a positive free energy and you could call those "biochemical reactions". --JWSchmidt 15:45, 1 November 2007 (UTC)

If you have a library card you can get help with homework here. 71.100.9.205 14:14, 1 November 2007 (UTC)

Put it another way: do all biochemical reactions in the body happen spontaneously? That is, do they all occur as soon as it is possible for them to occur? Think about what this would mean. SamuelRiv 14:32, 1 November 2007 (UTC)

Spontaneous human combustion? Clem 18:40, 1 November 2007 (UTC)

• SamuelRiv makes a very good point. (see Enzyme) - Mgm|^(talk) 09:18, 2 November 2007 (UTC)
• Thx SamuelRiv for your detailed explanation.

Blood phobia

How do extremely hemophobic women cope with getting their period? --124.254.77.148 13:11, 1 November 2007 (UTC)

With great difficulty I would imagine. Your question sort of reminded me of the Ashley Treatment. Short of hysterectomy or Endometrial ablation, I suppose they could reduce the number of periods they have using one of the many pills, but would still have to go through a few. Alternatively, maybe frequent exposure reduces the horror? Skittle 13:48, 1 November 2007 (UTC)

• FYI, the only reason women still have periods while on birth control pills is that some of them are placebos. For years, many women doctors have taken real BC all month long, and thereby never have periods at all. The FDA has recently started allowing such regimens to be marketed. --Sean 19:40, 1 November 2007 (UTC)

Yes, but even on those regimes you have to have a few periods a year, otherwise you get bleedthrough. Hence why I said you could reduce the number of periods using the pill. If I were unaware of the 'placebos' (they're not true placebos, more spacers to stop you losing track or getting out of the habit), I would have thought you had to have the same number. Skittle 17:22, 5 November 2007 (UTC)

constraints based on age

Is there a chart of minimum and maximum amounts (or rates) of oxygen, water, food, temperature, blood, exercises, heart rate, Vitamins, etc. within which the human body must stay to survive at different ages? For instance, heart rate probably has a narrower range for older people than for younger people as well as exercise, etc. 71.100.9.205 13:23, 1 November 2007 (UTC)

Probably not, as there are more factors than simply age which determine minimum requirements, and the "maximums" are often subject to a wide variety of opinions. Also, various factors often have an effect on the limits of other factors, meaning that having a lot of A or B could be fairly safe, but having a lot of A and B could be quite dangerous. Height, weight, health, and genetics are usually more important factors than age, especially after the body has reached maturity. Furthermore, people can be conditioned to survive extremes, such as the ability to handle low oxygen environments due to altitude training. As such, rates can only be given in the most general terms, like three days being about the limit people can normally survive without water, not in specific age-based charts like what you're asking for. -- HiEv 08:12, 3 November 2007 (UTC)

Exercise/muscle Pain

Why do personal trainers insist on creating so much pain for a person that hasn't exercised in a long while? What I mean is what benefit comes from torturing someone to the point that the next day they can't even climb stairs without extreme muscle soreness. I would think that muscle gain should be built up slowly over time. As mentioned in the earlier question, it appears that the popular explanation for muscle soreness are minuscule muscle tears. How can that be healthy?! --WonderFran 13:45, 1 November 2007 (UTC)

As I understand it, it's healthy because that is precisely the mechanism by which muscles build themselves up: each little tear is repaired by the muscle with stronger fibers, which over time can increase the strength and size of the muscle. See the heading "Recovery" at Strength training. On a larger scale, this would become a muscle strain. jeffjon 16:35, 1 November 2007 (UTC)

I heard the pain was caused by the buildup of lactic acid. They told me that in high school biology. — Daniel 23:38, 1 November 2007 (UTC)

The other relevant article may be DOMS. Vespine 23:59, 1 November 2007 (UTC)

The long-term lactic acid soreness idea is incorrect and based on a faulty experiment done decades ago. See Delayed onset muscle soreness. —Preceding unsigned comment added by SamuelRiv (talk • contribs) 14:34, 2 November 2007 (UTC)

• It would be very foolish indeed for a personal trainer to behave this way. Not building up intensity slowly increases the chance of injury, and greatly increases the chance that the victim will give up on exercising. If your PT did this, go find a new one. --Sean 15:37, 2 November 2007 (UTC)

• I agree. While "overdoing it" may build up muscles more quickly, "slow and steady wins the race", that's my hare of wisdom for the day. StuRat 16:01, 3 November 2007 (UTC)

Water - Oxygen redox?

Can water be considered chemically reduced Oxygen? Think outside the box 13:51, 1 November 2007 (UTC)

Yes. The burning of a mixture of H₂ and O₂ is just a redox reaction between them: hydrogen gets oxidized to H⁺ and oxygen gets reduced to O^2–, and the result of those is H₂O molecules. DMacks 14:15, 1 November 2007 (UTC)

Thanks DMacks, Think outside the box 14:17, 1 November 2007 (UTC)

Michelson-morley experiment

See WP:RD/M#Michelson-morley experiment or Wikipedia:Reference_desk/Archives/Miscellaneous/2007_November_1; answers already exist there (even if this is a more topical location) — Lomn 14:36, 1 November 2007 (UTC)

Game of life

When personal computers first started there was a game called truck driver which had the objective of seeing who could drive cross country for the least cost and highest profit in the shortest time. The program would throw flat tires at you or a gas station with a bad pump or an oil light. Is there a game yet to see who can live the longest at the least cost and greatest profit, most successful offspring with things like your car getting stolen or your house catching on fire, etc.? 71.100.9.205 13:55, 1 November 2007 (UTC)

Creating a game of that scope seems a bit excessive, but I suppose The Sims (or The Sims 2) isn't far off. Of course, there's also The Game of Life, which is fairly close to those parameters as well. — Lomn 14:17, 1 November 2007 (UTC)

Sounds like The Oregon Trail (computer game). Didn't realize how old that was. --— Gadget850 (Ed) ^talk - 02:19, 2 November 2007 (UTC)

Yeah, this is a bit better than truck driver in that there seem to be more things that can happen (variables). Is there anything like this say to prepare a student for college or even high school? 71.100.9.205 16:01, 2 November 2007 (UTC)

Gleason score image

I am trying to obtain orginal artwork for the image of the Gleason Scale that appears on Wikipedia. I know the copyright is in the public domain. Can you please advise where I can obtain the original artwork or any suggestions of where I can search for it?

Any help would be much appreciated.

Thank you for your help.

Most sincerely,

Sharon Strompf —Preceding unsigned comment added by 66.252.164.210 (talk) 16:29, 1 November 2007 (UTC)

(email, phone, etc removed) --Bennybp 16:47, 1 November 2007 (UTC)

If you're looking for the original image that User:InvictaHOG based the public domain image upon, it seems likely that the "1977 Scientific Article by Gleason" mentioned on the image page is the same as the article listed under "References" in the Gleason score article. Your local library might be able to help you track down that magazine article from "Urologic Pathology". jeffjon 18:18, 1 November 2007 (UTC)

5-digit "telephone" numbers

Where are / Who owns those 5-digit numbers that we (in the US) are encouraged to send text messages to, in order to vote for some contestant or enter a contest? Are they "real" telephone numbers?
(Once upon a time, there were 5-digit numbers for the old telex/tty network, but those were phased out decades ago, I believe replaced with standard-format numbers in the North American Numbering Plan, area codes 310/510/710. Has *that* technology been resurrected??) (By the way, if there's an answer to this in Wiki already, it's buried too deep, or it's too hard to ask the right question to find it...) 66.47.7.76 17:13, 1 November 2007 (UTC) DanH.

See Short code. -- Coneslayer 17:33, 1 November 2007 (UTC)

(after edit conflict) Based on this question/reply at Google Answers, they are called Common Short Codes. Having just taken a gander at the "what links here" page for Common Short Codes, I don't know how you'd have found that without knowing what to look for. I wonder what other articles might constructively link there so it's more easily found? --LarryMac | Talk 17:38, 1 November 2007 (UTC)

Awww, I was gearing up to do a whole historical dissertation on the old "KLONDIKE-5 1212" type numbers. :) Arakunem^Talk 17:40, 1 November 2007 (UTC)

I found Short code from Text messaging (and had come across the term before—I couldn't remember it, but I knew it when I saw it). I've added merge templates to propose merging Short code and Common Short Codes. -- Coneslayer 17:41, 1 November 2007 (UTC)

Actually Common Short Codes looks like a fork started for promotional purposes. It was a redirect, then someone replaced it with promotional material. Probably a spammer working for a related company. In fact, the text is entirely taken from usshortcodes.com [1][2][3]. I'll tag it and we'll see what the copyright police think. --tcsetattr (talk / contribs) 21:19, 2 November 2007 (UTC)

I stand IN AWE of the user community here. Half an hour, and everything I wanted to know appears as if by magic. Thanks to All! 66.47.7.76 19:06, 1 November 2007 (UTC) DanH.

Particle geometry

The components of the nucleus of an atom, protons and neutrons, are always shown as individual spherical particles. While this must of course be the case when they are not part of the nucleus of an atom, is it correct to assume that when in the nucleus of an atom they loose their individual spherical shape and become combined into a single spherical mass or globe called the nucleus until an imposing force adds or subtracts one or another or splits the atom in two or do they maintain their own independent spherical shape within the nucleus? Clem 18:27, 1 November 2007 (UTC)

I don't know what distortions may occur, but individual nucleons will remain individual nucleons. Since nucleons lack a color charge, they don't interact nearly as strongly as quark pairs, and a giant conglomerate mass of quarks would actually be quite unstable, evidenced by the difficulty of building stable quark structures larger than nucleons within particle accelerators. Someguy1221 19:47, 1 November 2007 (UTC)

I’m not an expert in nuclear physics, but I’m pretty sure I know the right answer by analogy to atomic and molecular physics:

Even representing a nucleon as a sphere is to some extent just a representational device to aid in comprehension. No bound state has a precisely defined boundary like a sphere. Picking a particular radius for a sphere representing a free nucleon involves somewhat arbitrarily choosing a particular “equipotential surface” (although that’s not quite the right phrase) of the nucleon’s wavefunction.

The wavefunction for a nucleus is different from just the sum of the wavefunctions of a bunch of free nucleons, so in that regard you could think of the nucleons as “changing shape.” But in reality, there are no precise boundaries between where one nucleon ends and an adjacent nucleon begins. MrRedact 20:43, 1 November 2007 (UTC)

On the other hand, even if the best we can do is some sort of equipotential surface or probability cut-off, that doesn't mean we can't talk about the shape of that...thing. It's not the physical boundary in the sense of interactions such as touching or seeing but it's still a useful description if you care about electrostatic potential, electron distribution, nuclear-capture cross-section, etc. Interestingly, Nuclear isomer teaches us that spherical is not even a good approximation for the nucleus (though it certainly suffices in most situations). DMacks 20:50, 1 November 2007 (UTC)

There’s a complication here in that the exchange symmetry of identical particles makes it impossible to define precisely which of two identical nucleons exists at a precise location. I’m pretty sure there really is no way to define a precise boundary between adjacent nucleons with complete accuracy. Any concept of the "shape" of a nucleon in a nucleus has to be at least a little bit vague. But I don't know enough about nuclear physics to come up with numeric values for "how vague" it has to be. MrRedact 21:41, 1 November 2007 (UTC)

To clarify... what I'm asking is whether the protons and neutrons which make up the atomic nucleus exist in a geometry similar to a bag of marbles or whether they meld and exist similar to the configuration of a two component sphere like water and oil at zero gravity inside a water (and oil) balloon? Clem 03:47, 2 November 2007 (UTC)

Ignoring all quantum mechanics about the particle (or group of particles) itself, it will be a sphere as its interactions are spherically symmetric, no matter how many nucleons make up the nucleus. This isn't 100% true, as there is one biased direction: that of angular momentum or spin, so the nucleus actually will "look" like an ellipsoid for most measurement purposes. Numerical analyses of particle accelerator data seem to agree with an ellipsoidal geometry for most individual particles and bound states. SamuelRiv 04:00, 2 November 2007 (UTC)

More like a bag of marbles. You can model an atomic nucleus very well by treating the protons and neutrons as almost-free particles that interact with each other occasionally. They definitely do not meld together to the point of making quark soup. As Steve and others point out, the "bag of marbles" is not a perfectly spherical bag, but can be stretched out in certain directions. There is also a bit of quantum mechanical fuzziness on the identity of nucleons inside the nucleus, but the "bag of marbles" is a good picture. The protons and neutrons don't all melt together. --Reuben 07:34, 2 November 2007 (UTC)

To refine this picture a little, since according to Reuben the particles are almost free, maybe you could think of the nucleus as a bag of marbles that can magically pass through each other. MrRedact 08:00, 2 November 2007 (UTC)

The nucleus of some atoms are slightly cigar-shaped [4], one example being tantalum-180. [5] For the individual nucleons (protons and neutrons) however, it would be wrong to say that they have ever been spherical, seeing as they'r each made up of three point-particles and the force carriers between those. That said, while their location is not necessarily well-defined, we can say that they don't "melt", as they don't, to my knowledge, exchange quarks with each other.

See liquid drop model. Gandalf61 16:59, 2 November 2007 (UTC)

Electrical path

If your elbow say were grounded but your feet and the rest of your body were well insulated and your fingers touched an exposed appliance cord, say in the UK where line voltage is 240, would the electricity travel between your fingers and elbow or would it travel through other parts of your body as well? Clem 20:53, 1 November 2007 (UTC)

The current density would be highest between the two contact points, along the "path of least resistance" as they say. —Keenan Pepper 21:44, 1 November 2007 (UTC)

However, the distribution of current density can be quite complicated and difficult to calculate. See Analysis of Current Density in the Carpal Tunnel Region During an Electrical Accident by way of the Finite Element Method (PDF link) for an example. —Keenan Pepper 21:51, 1 November 2007 (UTC)

(edit conflict) I had to go get my thinking cap out of the closet for this one. Almost all of the current would take the short path, but I would think that some electrons in the rest of your body would move. Current flows through every path available to it as long as there is a potential difference, in proportion to the resistance it encounters. Some of the tissues in your forearm will have relatively low resistance, blood probably having the lowest. Your circulatory system is a network, and the current will see a path all through it, mostly in the straight line, but some more roundabout. It's a bit like having a 50-ohm resistor in parallel with a 50-meg, say. The same goes for all your tissues, but to a lesser extent, I would think. But in my experience (is that allowed here?), the current in the rest of the body at 240V will be negligible, and you'll be too busy trying to extinguish your fingertips to even notice it. --Milkbreath 21:59, 1 November 2007 (UTC)

Assuming the capacitance of the rest of your body to earth was small, almost all the electric current would flow between your fingers and your elbow. In practice, the capacitance of your body to ground would not cause appreciable( dangerous) currents to flow through the rest of your body. —Preceding unsigned comment added by 88.111.55.77 (talk) 02:23, 2 November 2007 (UTC)

From personal experience, I'll say it felt like it went straight from my hand to my elbow, however I should note that it was my right hand and my left elbow. Fortunately for me the current had already been stepped down, so I was surprised, but uninjured. -- HiEv 09:20, 3 November 2007 (UTC)

Unlimited source of free energy?

If there was a device that did nothing all day except turn neutrons into protons would we have a source of unlimited energy? Dichotomous 21:14, 1 November 2007 (UTC)

• You'd run out of neutrons after a while. It's probably worth elaborating that there's a finite (if large) number of neutrons within the observable universe, and a much smaller fraction within your future light cone (assuming, of course that w = -1, so there are only so many neutrons you could collect. Cheers, WilyD 21:16, 1 November 2007 (UTC)

And most neutrons tend to be very annoyingly inside of atoms, and for the majority of matter in the universe, extracting those neutrons would require more energy than you'd get from fusing the resultant protons. Someguy1221 21:25, 1 November 2007 (UTC)

Exactly. A free neutron has more energy than a free proton, but a helium-4 nucleus has less energy than the sum of two free protons and two free neutrons (because of the attractive nuclear force that binds them together). So your device wouldn't work, because we don't have an unlimited source of free neutrons. —Keenan Pepper 21:32, 1 November 2007 (UTC)

Although as the hypothetical device seems to violate charge conservation, then I guess anything is possible. Gandalf61 16:56, 2 November 2007 (UTC)

Besides, we already have an unlimited source of free energy, the Sun, which puts out around 400 yottawatts, 24 hours a day, 365.2425 days a year. The hard part is collecting it. Even if we had a (conservation-law-violating) device which converted protons into antiprotons for free, it would be hard to build a safe and reliable power plant around it. The devil is always in the details. -- BenRG 17:13, 2 November 2007 (UTC)

lab procedure- AP Chem exam style question

Could anyone please help me with these two questions?

1. Explain how you would go about making 3.00 L of 0.005 M NaOH. Include lab materials that you would use and diffrenet steps you would take in preparing the solution. (Hint: NaOH is solid at room temp.)

2. Explain how you would go about m,aking 3.00 L of 0.500 M H₂SO₄. Keep in mindo that H₂SO₄ is a strong acid and starts out as a 12.00 M solution.Include lab materials that you would use and diffrenet steps you would take in preparing the solution. —Preceding unsigned comment added by 76.214.218.77 (talk) 21:37, 1 November 2007 (UTC)

Materials: 1 grad student. Method: "Hey you, make me 3 L each of 0.005 M NaOH and 0.5 M H2SO4."

Seriously though, the reference desk is not a homework answer service. Dragons flight 21:57, 1 November 2007 (UTC)

"Do your own homework. The reference desk will not give you answers for your homework, although we will try to help you out if there is a specific part of your homework you do not understand. Make an effort to show that you have tried solving it first." -- MacAddct  1984 ^{(talk • contribs)} 00:08, 2 November 2007 (UTC)

Medical question

I just cut my head off. What sort of treatment is appropriate? --67.185.172.158 23:58, 1 November 2007 (UTC)

I hear snake oil is a very effective cureall -- MacAddct  1984 ^{(talk • contribs)} 00:05, 2 November 2007 (UTC)

1) Immediately apply a tourniquet to your neck to stop the gushing of blood from your carotid arteries.

2) Put your head in a cooler, and pack the cooler with ice.

3) Dial 911, and use Morse code to request an ambulance to take you to the nearest emergency room.

Don’t delay, as decapitation could be a sign of a serious medical condition. MrRedact 00:40, 2 November 2007 (UTC)

And decapitations lasting longer than four hours may require the treatment by an undertaker.

Atlant 12:20, 2 November 2007 (UTC)

Wikipedia cannot give medical advice. I understand you're all busy, with the bleeding and the flopping around and all, but you should take time to read the disclaimers at the top of the page before posting a question!! Deltopia 02:02, 2 November 2007 (UTC)

Man, cut them a break! (well, maybe it's too late on that part.) Their head (the part with the eyes) knows this, but there's no way any more to get that message to their fingers!

Atlant 12:23, 2 November 2007 (UTC)

Dr. Hill has been through this before. --— Gadget850 (Ed) ^talk - 02:25, 2 November 2007 (UTC)

Thanks, Deltopia, but it's pretty hard to coordinate the scrolling-up, given that what usually controls such muscle movement is not attached to them. Maybe if I blink someone will do it for me? Meh, tis only a flesh wound. DMacks 05:48, 2 November 2007 (UTC)

Burial. Dragons flight 02:31, 2 November 2007 (UTC)

We aren’t allowed to diagnose your condition. However, on a completely unrelated topic, our article on decapitation could use some editing. MrRedact 03:47, 2 November 2007 (UTC)

Hmmm - it's kinda gross though - we don't want editors with Post-traumatic-editing stress disorder. I recommend we organise a team and send each editor in to work on the article for no more than 30 seconds apiece. SteveBaker 15:37, 2 November 2007 (UTC)

If only you had thought to do this earlier in the week, you could have been star guest at a Halloween party. Gandalf61 16:50, 2 November 2007 (UTC)

You need to plug your neck's blood-in and -out into a looped pump that oxygenates it. That will give you enough time (a few hours) to add some nutrients to your blood such as fish food or better. Russians used to do it in the 50's with dogs. Ah the good old days. Keria 17:00, 2 November 2007 (UTC)

Article at Experiments in the Revival of Organisms. I guess Laika was one of the lucky ones. risk 03:49, 3 November 2007 (UTC)