Wikipedia:Reference desk/Archives/Science/February 22–28 2006
February 22
editgeography
editI want to know the 10 largest states in the USA by land area; and with the list does it include the mountain and hill heights and lake or bay areas?
- The 5 largest are the Great Lakes, assuming you're including the 4 which are half in the US and half in Canada. StuRat 02:17, 22 February 2006 (UTC)
- But he asked for states, not lakes. The five largest states, including water area, are Alaska, Texas, California, Montana, and New Mexico, in that order. Next come Arizona, Nevada, Colorado, Oregon and Wyoming. - Nunh-huh 02:32, 22 February 2006 (UTC)
- Oops, time to go to a larger font I see, LOL. StuRat 03:07, 22 February 2006 (UTC)
- If it's any consolation, I also read "10 largest lakes" the first time through. Anyway, I expect we have a list at list of U.S. states by area. — Lomn Talk 14:00, 22 February 2006 (UTC)
- So did I. How weird? Considering the title of the question is "Geography" and he wanted "mountain and hill hights", which totally confused me. freshgavinG??? 15:48, 22 February 2006 (UTC)
- Strange, Nevada "used to be" 6th. Maybe there's been some cartographic clarification in the past few years.
- You might want to check the data on that. Wikipedia tables are notoriously false-y. freshgavinG??? 04:32, 24 February 2006 (UTC)
- And do your own homework. -Tim Rhymeless (Er...let's shimmy) 12:03, 27 February 2006 (UTC)
Antarctica
editI asked a question earlier about un-explored regions of the Earth. The article on Anartica refers to lakes under the ice. Is possible to drill through the Ice and explore the Lakes submersively, and if possible how hard would this process be?
- This is complicated by the fact that the ice is all moving, and even moving at different rates and directions at different depths. This makes it difficult to keep a hole open long enough to drill all the way through. StuRat 02:13, 22 February 2006 (UTC)
- Also, there is concern about contaminating the lake with the drilling apparatus. StuRat 02:22, 22 February 2006 (UTC)
- I imagine it would be most (or somewhat) feasible with a robotic camera-equipped drill that could navigate in water once it broke through. Still sounds like it would take a mother of an expensive robot to manage that though. freshgavinG??? 15:44, 22 February 2006 (UTC)
Expanding on StuRat's answer: yes, it is eminently possible to drill into the subglacial lakes -- in fact the Russians at Vostok Station had drilled to within 120 meters of the biggest one when they stopped, deliberately, to avoid contaminating the lake. The water in it is thought to have been undisturbed for at least half a million years, and to have oxygen levels 50 times higher than normal, and to perhaps support life -- and if there is life there, it'll be unlike anything we know. See our Lake Vostok article for more information. --Steve Summit (talk) 16:35, 22 February 2006 (UTC)
- Excellent article. Seems that there's a high risk of it popping if we stick a hole into it, so I guess we'll just have to enter it from underneath instead. freshgavinG??? 21:07, 22 February 2006 (UTC)
- One of the proposals for exploring Europa was to melt through the ice with a heated robot submarine (the hole refreezing behind it) to explore the liquid sea below -- anyone know whether that technology might be tested in Antarctica? Ojw 21:34, 25 February 2006 (UTC)
March of the Penguins
editI saw this film recently and felt bad about the penguins having such a rough life trying to balance an egg on their feet in the cold and harsh winds. Couldn't humans build some sort of shelter to make the habitat more hospitable? We obviously know where to build it, we just need a design and someone to go down there during the summer to put it up. Maybe a pyramid or teepee design with entrances on one side so the wind will not blow through. Anything's better than what they have now.
- Why disrupt their habitat and natural life? They've been doing this for thousands of years, and it worked. Humans don't need to interfeer. ? ?i?ff?? 05:42, 22 February 2006 (UTC)
- They are used to the cold. They would think we are miserable in the heat and want to build us an ice path to keep us nice and cool, like they are. StuRat 06:40, 22 February 2006 (UTC)
- Heh, good point StuRat. I'd like to add that too often when humans interfere with nature we mess it all up. Imagine us 'trying to help them' and ending up with them dead. Flea110 07:07, 22 February 2006 (UTC)
- Well, they may have developed the habit under different climatic circumstances and not really be adapted to the present situation. Maybe they're only just barely hanging in there. Nature is in a constant state of flux. Maybe they're destined to extinction if the climate doesn't get any warmer. So maybe we're already helping them. This makes me think of this science fiction story that describes these scrawny furless animals that lived on a very cold planet, about which people wondered why they weren't cold all the time and then went on to say that if anyone had bothered to learn their language they would have found out that they were constantly complaining about the bloody cold. DirkvdM 09:23, 22 February 2006 (UTC)
- I recently read the distance they had to travel to get their food had increased because there was an additional piece of ice they had to pass. If there's anything we should be helping them with is to make sure they get to their food easily. 0- Mgm|(talk) 09:55, 22 February 2006 (UTC)
That was another type of penguin. It was so sad. I was always watching them nesting with the penguin-cam, then they suddenly abandoned their nests and took off. --Zeizmic 13:26, 22 February 2006 (UTC)
It seems like a very compassionate idea. I've seen peguins at zoos and aquariums, not bothered at all by the warm climate. Happy, active, playful. Why does everyone agree that nature ought to be harsh (even if it is). We humans make ourselves and our pets comfortable, don't we? I think the poster might have been talking about Emperor penguins. I think the males are the ones who incubate their children this way. But I seriously doubt that the peguins would see the advantage of shelter, and use it. Or would they? Hey, that's an idea! Posed as a research question, it could be done. Probably even funded. --Leah
- I think once we start interfering with nature to make animals lives better than our human perceptions see that they are, it isn't nature any more, it's a zoo. Of course, many people would be happy with the world being a well manicured zoo. Humans have a pretty terrible record for preserving nature, why do we think that good intentions will achieve more than any other idea in the past? Notinasnaid 14:03, 22 February 2006 (UTC)
- Do ya really think a wild peguin would actually use a shelter? I've got some more good ideas - how about introducing cane toads to eat cane beetles (sp?) it would make humans and toads happy. All in fun, Leah
- Seriously, I bet it would only disrupt their nesting and mating routines, threatening their survival ~ Leah
- And it would be a real bane on Antarctica's tourist industry. freshgavinG??? 15:38, 22 February 2006 (UTC)
- Whoa!!! I just found the strangest coincidence. On the 15th Feb Notinasnaid responded to a post about cane toads and anesthesia! How wierd. I had NO idea. Mea Culpa. You must have thought I was being so sarcastic. Sorry. It'll just teach me to keep my big trap shut ~ Leah :)
- No, actually I was the one being sarcastic. I think antarctica's tourist industry would do just fine. freshgavinG??? 17:25, 22 February 2006 (UTC)
- Antarctica - enjoy a luxury six day, seven night stay in beautiful South, South, Planet Earth. Book NOW.
- "Enjoy our secluded, rustic beaches in this southern paradise. You never have to worry about mosquitos here. And as a bonus, we have the longest summer days anywhere on Earth." StuRat 08:28, 24 February 2006 (UTC)
- I watched the film and understand why this question was posted. The enormous effort the Penguins parents made to protect their eggs and feed their youngs put many homo sapiens to shame. And no, the eggs are not adapted to the cold, they require constant protection from the parents who had to endure such terrible discomfort. It's amazing how the penguins survive at all. Yes, I think they would like some help; but first, we must stop messing the environment and the global warming stuff. --Vsion (talk) 10:07, 24 February 2006 (UTC)
Units
editwhat s the difference between the units joules and ergs? —The preceding unsigned comment was added by 59.92.114.71 (talk • contribs) .
- A joule is equal to ten million (107) ergs. —Keenan Pepper 05:19, 22 February 2006 (UTC)
- Did you know that if you go to Google, it can help with unit conversions? Try typing (not the quotes) "1 joule in ergs". It can also do things like "1 US gallon in liters". -- SGBailey 23:43, 22 February 2006 (UTC)
- It can also tell you that Planck's constant is about one stone barn per fortnight. :) --Heron 20:24, 26 February 2006 (UTC)
Digestion of Key Lime Pie
editHmm...how long does it take to digest a piece of key lime pie? --HappyCamper 05:09, 22 February 2006 (UTC)
- Depends when you consider it to be digested. —Keenan Pepper 05:22, 22 February 2006 (UTC)
- Well...key lime pie has lots of sugar and fat. How long does it take for the body to dissolve all this in the stomach so it does not feel "full"? --HappyCamper 05:35, 22 February 2006 (UTC)
- Sugars are quickly digested, but fats are slow. They don't dissolve in the stomach but in the small intestine. This can take several hours. For this reason, you might have noticed that a meal full of fats seems more "satisfying". StuRat 06:32, 22 February 2006 (UTC)
Projectile motion
editDoes the direction of force of air resistance keep on changing as a projectile moves thru air? Is the path of the projectile still a parabola (as in the ideal situation of vacuum)?
- Air resistance always acts in the opposite direction to the velocity vector of the projectile. Path will be parabolic, assuming gravity. — TheKMantalk 06:03, 22 February 2006 (UTC)
Then how will the air resistance affect the direction of motion and its parabolic path?
- If the air is still, then the direction is always opposite the current direction of the projectile, just like friction. If the air is moving at high speed, then that would also need to be taken into account. No, the shape isn't parabolic anymore, but looks more like this:
* * * * * * * * * * * * *
StuRat 06:13, 22 February 2006 (UTC)
Well, air resistance is a function of its velocity. Air resistance will cause its velocity in the x-direction to slow down to near zero. Force from air resistance will act against motion in the y-direction, and decrease the net acceleration in the downward direction. And yes, the path won't look entirely parabolic anymore. — TheKMantalk 06:21, 22 February 2006 (UTC)
- You can observe this effect well with shuttlecocks - their high drag and low mass make them particularly susceptible to the effects of air resistance. If you hit a shuttlecock at a moderate angle, it will follow a more or less straight line until its apex, at which point it will seem to fall almost straight down (very low or no x-velocity). This makes 'clear shots' in badminton possible, where the shuttlecock flies high over the other player and lands almost vertically on the rear line of the court. — QuantumEleven | (talk) 14:05, 22 February 2006 (UTC)
- You just wanted to say cock and not get in trouble for it. freshgavinG??? 15:35, 22 February 2006 (UTC)
- Darn, caught again! ;-) — QuantumEleven | (talk) 08:53, 23 February 2006 (UTC)
- Have a look at [1]. It's a Flash simulation of projectile motion. I think it's quite good. 80.229.152.246 15:03, 23 February 2006 (UTC)
atomic structure
editwhat is the role of neutron in an atom? explain it in detail.
thank you, mani
aerodynamic terms
editwhat do the following terms mean? - velocity field - flow field - flow pressure - shear distribution
- Velocity field - velocities at certain points, over a given range, around an airfoil
- Flow field - representation of air flow moving around an airfoil
- Flow pressure - air pressure of the surrounding atmosphere (flow)
- Shear distribution - distribution of the shear stresses on the wing, perpendicular to its surface, due to the air flow moving around it. — TheKMantalk 06:44, 22 February 2006 (UTC)
Wikilink wait
editQuite often, after clicking a wikilink, nothing happens. I wait ten seconds or so, then click again, and I am instantly taken the page I want. Is this normal? Is it a quirk of my PC, of the Internet, or of Wikipedia? --Shantavira 11:51, 22 February 2006 (UTC)
- You wait ten seconds before clicking again?!? You must be the most patient person in the world. David Sneek 13:31, 22 February 2006 (UTC)
- It could be any number of things, although most likely it's Wikipedia. Have you experienced this behaviour on other sites? If so, then your connection might be at fault, although the symptoms you describe make it sound unlikely. Wikipedia's servers are continually overloaded (the site's traffic is increasing faster than they can collect donations to buy more equipment), and so the server might take some time to respond to your first request... — QuantumEleven | (talk) 14:01, 22 February 2006 (UTC)
- Is it just me, or has it been getting a lot worse recently? I'm worried if Wiki is managing with the server upgrades (they imply that they are). I had to click [edit] 3 times to add this comment - -;;. freshgavinG???
- Well it's a helluva lot better than it was a year ago. Other sites vary. What I don't understand is why a first request should so often not work, when a second request works straight away, well, usually. --Shantavira 18:30, 22 February 2006 (UTC)
- The problem of the first request going unfulfilled but the second request working immediately has been noticed before. I have notcied this problem at a computer lab at my uni (WinXP, proxy). Someone on the help desk also had this problem and no explanaion was found. You are not the only one.--Commander Keane 18:56, 22 February 2006 (UTC)
- It's probably nothing but the "buttered side down" effect. If your request to the server is lost 50% of the time then you'll have a 50% chance of success on the first click, and a 75% chance of it working by the second try. freshgavinG??? 20:58, 22 February 2006 (UTC)
- No, I have noticed this too, and it's definitely different on Wikipedia. Ever since I noticed this here, I started to use the repeated request thing on other sites as well. I imagined it worked there too, but it's not quite as noticeable as on Wikipedia. The point is that a later (the second or third or fourth) request gives an instant response. On the other sites it may very well be what you say, but not here. DirkvdM 12:38, 23 February 2006 (UTC)
- I imagine the reason why it works instantly after consecutive tries is that the first/second/third requests were lost/dropped by the server for some reason. It is quite pronounced on Wikipedia, and apparently it was much worse a year ago. Since it's a server side problem there's no reason to assume that it would happen on other servers (in the same way) as well, unless they were having similar problems. I can remember back in the dial-up age when the line quality was low I would have to click links repeatedly until the server finally received my request at which time the page would quickly be downloaded. freshgavinG??? 16:06, 23 February 2006 (UTC)
- No, I have noticed this too, and it's definitely different on Wikipedia. Ever since I noticed this here, I started to use the repeated request thing on other sites as well. I imagined it worked there too, but it's not quite as noticeable as on Wikipedia. The point is that a later (the second or third or fourth) request gives an instant response. On the other sites it may very well be what you say, but not here. DirkvdM 12:38, 23 February 2006 (UTC)
Excel cell formatting
editI have a very crowded table. How do I format a cell in Microsoft Excel so it only shows the lower two digits of a year? e.g. 1986 -> 86; 2003 -> 03. -- Toytoy 12:19, 22 February 2006 (UTC)
Highlight the cells / column / row. Right click on them, and pick 'Format Cells'. Pick the 'Number' tab (the one on the top left), and you will be able to adjust the format of these cells. Go to 'Custom' (the bottom one of the list), and enter in yy as the format. If the cell displays a full date (such as 14th Feb 1998 or 02/14/1998) then you will need to experiment, trying things such as dd mmm yy or mm/dd/yy to get the correct formatting you require. Proto||type 12:29, 22 February 2006 (UTC)
- I tried yy before asking this question. My table contains a long range of years (numbers; not full dates; e.g. 1978, 1979, 1980 ...) as categories. I tried yy and Excel treats the numbers as dates under the 1900 system (1985 = 5 years after 1900 therefore it displays 05 from the beginning to the end). Setting these cells as text also does not solve the problem. -- Toytoy 13:25, 22 February 2006 (UTC)
- So if you just have year numbers and you want to lose the century, create a new column, populate it with formulas like "=MOD(A1,100)" (where your full year number is in cell A1) and use 'Format'/'Custom' to set cell formats to "00" so that leading 0s are displayed (so "1901" becomes "01" not "1"). Then hide the old column.Gandalf61 14:55, 22 February 2006 (UTC)
Light or dark clothes in hot climates
editI feel very stupid asking this, but I can't seem to figure it out myself. In a hot climate with strong solar heating (eg a desert), does wearing light colours help to keep cool(er)? My first answer would be yes - light colours reflect more incoming light, so less is absorbed, ergo less heating of the clothes and therefore the body underneath it. But than I started thinking... what we perceive as colour is just absorption/reflection in the visible spectrum, how does colour match to absorption/reflection in other parts of the spectrum, specifically in this case, infrared?
Also, I remember being told in geography class that while light colours keep cool, very dark ones (ie black) do too, due to some effect with a layer of air being built up under the clothes (I am referring specifically to voluminous, all-covering clothes, not shorts and t-shirts). Is there any truth to this, or is my memory (or the teacher in question :)) just wrong? Thanks in advance! — QuantumEleven | (talk) 15:32, 22 February 2006 (UTC)
- how does colour match to absorption/reflection in other parts of the spectrum, specifically in this case, infrared—pretty closely. One experiment that demonstrates this involves placing two pieces of cloth, one light and one dark, on top of sunlit snow. The snow underneath the dark cloth will invariably melt further. If you don't have snow handy, you could try leaving the cloths out in the sun for a while and then measuring their temperatures.
- This suggests that voluminous dark robes, such as those worn by the Bedouin or Tuareg, cool the wearer by creating constant air circulation. Basically, as the air underneath is heated by the sun, it rises, which in turn draws in cooler air from the bottom of the robe.
- on the other hand, closer-fitting clothing (not shorts and t-shirts—any idiots who wears those in a desert deserves exactly what they get) cools the wearer better when it is light-colored. —Charles P._(Mirv) 16:42, 22 February 2006 (UTC)
- With respect to your first question, you are working under the (quite common) mistaken assumption that infrared = heat. This assumption is caused by the fact that our bodies emit radiation within the IR range of the electromagnetic spectrum, and so IR can be used to distinguish warm bodies (by our standards) from cold in night vision and other applications. In fact, the energy of the waves is not related directly to their frequency, but rather to their radiant energy. This means that you are being warmed by all the wavelengths emitted by the sun. Therefore wearing white clothes, which block out a large proportion of those waves, will indeed keep you cool. — Asbestos | Talk (RFC) 16:54, 22 February 2006 (UTC)
- Plus that, the maximum of intensity of solar radiation lies in the visible region of spectrum. So, reflecting light in this region of spectrum is more significant than reflecting light in other regions of spectrum under given conditions. 62.63.83.24 17:04, 23 February 2006 (UTC)
- Supplementary question: So why do natives of hot climates have dark skin, and natives of cold climates have pale skin? Shouldn't it be the other way round to effect the most efficient maintenance of body temperature? --Shantavira 18:35, 22 February 2006 (UTC)
- It's not to do with cooling, it's pigmnts that protect against uv radiation. —The preceding unsigned comment was added by 67.40.249.122 (talk • contribs) 20:12, 22 February 2006.
- and Vitamin D production; see melanin. —Charles P._(Mirv) 20:30, 22 February 2006 (UTC)
- Thank you very much everybody - you learn something new every day! Asbestos, thanks for putting me straight on my misconception, I guess had never really thought about it in depth before, which is very embarassing, but at least now I know better.
Kudos! — QuantumEleven | (talk) 08:52, 23 February 2006 (UTC)
- Thank you very much everybody - you learn something new every day! Asbestos, thanks for putting me straight on my misconception, I guess had never really thought about it in depth before, which is very embarassing, but at least now I know better.
Packets/Bytes interconversion
editGreetings:
Below is a screenshot taken of my IEEE 1394 Firewire LAN connection.
However, the unit of measurement used is "packets" instead of "bytes".
I am wondering: is there anyway of changing the unit by which Windows measures thruput for this particular connection? I also have a regular Ethernet connection to the Internet on a different interface (a regular LAN NIC), and Windows reports that connection in units of bytes, so I am confused as to why Windows would measure connections differently if they all use the TCP/IP protocol.
Also, in the case where it's not possible to change the measurement unit. Could anyone tell me how to manually convert packets into bytes?
Regards,
L33th4x0r 16:00, 22 February 2006 (UTC)
- You can only convert from packets to bytes if you know the average packet size. Without that information, it's not possible, sorry. --cesarb 16:18, 22 February 2006 (UTC)
- Although, being a l33th4x0r I'm sure you have access to such l33t information. freshgavinG??? 17:21, 22 February 2006 (UTC)
- Thinking out loud: can't Ethereal count bytes? Sum0 23:22, 22 February 2006 (UTC)
Installing Linux on old, crappy ThinkPad
editI am in possession of an old IBM ThinkPad 770E. It has a Intel Pentium II Processor. It has two hard disks, both about 2.5GB. It has a working CD-ROM drive. It has USB ports, but I have had no success using those for anything. It does not have an ethernet port, so I cannot directly hook it up to the network. It does not have a working battery - it must be plugged in at all times or it shuts off immediately. It came installed with Windows NT 4.0. Then we installed Windows XP, and used that for a while. After a while, that became unusable with viruses, so we reformatted the hard drives and deleted Windows all together. Now the hard drives are empty. I have successfully gotten Puppy Linux and DSL to run off of Live CDs. I have been unable to install them to the hard drive, and I am not sure why. My other computer is an Apple eMac, running Panther. I installed a burner into it myself, but it has broken recently, so it will be difficult for me to burn any more CDs. I could if needed, but I would prefer not to. I have a NetGear Wireless Router and a NetGear Wireless PC Card, model #WG511. I need to be able to use that on the ThinkPad once I get Linux installed. So basically, this is my situation. I would consider myself of advanced knowledge in computing skills and such, however, I have practically no experience running commands and programming (ie: Terminal). All your help is greatly appreciated! Thank you much! -zappa
- Can you expand on "I have been unable to install them to the hard drive"? What exactly happens (symptoms, exact error messages etc.) Notinasnaid 17:47, 22 February 2006 (UTC)
- I'm going to put the Puppy Live CD in the drive and go from there. Here's the stuff it tells me when it pauses: (normal ThinkPad stuff) ISOLINUX 3.11 2005-09-02 (here I hit Ctrl+Alt+Del) (more ThinkPad stuff again) I choose a normal boot (default) (does a ton of crap) The following appears in red text:
- Puppy cannot find a suitable partition for your personal data file. If you want to use a USB drive for this purpose, type "sda1" then press ENTER key, else just press ENTER key to run Puppy totally in ramdisk. In the latter case, no personal settings or data will be saved. The USB Flash or hard drive must have a MSDOS or VFAT partition. (this question will be asked everytime Puppy boots -- to make the USB drive the default choice, you need to remaster isolinux.cfg with "PHOME=sda1") (the USB partition is likely to be sda1, however if you know it is something else such as sda2 or sdb1, then type that instead) Press ENTER key, or plugin USB drive then type "sda1" and ENTER:
- (I do have a 128MB USB flash drive, but I have tried doing stuff with that and it didnt work. I have a 80GB hard drive that is mostly full, but it has data on it I cannot lose, and I cannot store elsewhere. Could I do something with this drive? I'm afraid to try...) Anyways, here I press ENTER. (more stuff) (here it says some stuff, about a problem, in regular text, and it says "pausing for 30 sec so you can see this bad situation". I can't read it all in that short time and type it. I will put new batteries in my digital camera, take a pic, and then edit in that stuff soon. After the 30 sec, it gives me some red text, and says "pausing for 10 sec s you can see this bad situation". I'll do the same thing for that. Then it gives me some more stuff.) Now it askes me to select the keyboard map. I select the "us qwerty" and hit OK (everything goes ok) Now it asks me to select the mouse type. I have one of the little red dots in the middle of the keyboard and the clicker buttons with your thumb. I didn't know what that would be, so I have gone with, and still go with, the default, ps/2. The other options are USB and serial, and those don't seem any better, so I'll stick with ps/2. I hit OK. It asks me if I have a wheel/scrool type of mouse. I do have a button for that, so I hit yes. It takes me to the video wizard, with some complicated crap, and I just go with the default, with what works better with a slow computer. I choose Xvesa, as opposed to Xorg. On a small screen, it asks me to choose my resolution. I do, the screen blacks out and then gets bigger, and then finally Puppy is booted. So yeah, that's how it goes. I will get the other stuff for you soon, later today. I cannot find the DSL disc, if you need me to run that, I will ASAP, but it probably won't be until around Saturday. Thanks a ton! -zappa 19:43, 22 February 2006 (UTC)
I love installing Linux on old crappy laptops. The crappier the better! As for the network connection, get an old crappy PCMIA ethernet card. You really, really need to be able to write RW cds with your other computer, connected to broadband, because there is a lot of stuff to download. There might be some BIOS stuff to check, but the general idea is to write a cd with a distribution network install disk (I use Debian), and then bring in the rest by network. I've only had trouble with really new hardware. --Zeizmic 18:33, 22 February 2006 (UTC)
- Do I need both CDs and the ethernet connection? I'm thinking basically I just have to transfer files, so wouldn't I just need one mode of connection? -zappa 19:43, 22 February 2006 (UTC)
Yes, there is a limitation to the degree of crappiness, especially for those of us who choose to be not that smart ( :). It works best if you can boot off a cd. The USB of old crappy laptops can be tricky. You can just go pure cd, but that's a crapload of cd's. --Zeizmic 21:03, 22 February 2006 (UTC)
Zappa, it sounds like Puppy is expecting to find a partition of some sort. That's also the impression I get from glancing at the docs. So if you've completely wiped the drives, you probably need to fdisk. - mako 22:00, 22 February 2006 (UTC)
- Need to what? Please explain, I am very new to Linux, programming, commands, that stuff. As far as working in a GUI (especially OS X) I am great, but I can do nothing at the system-level.
- fdisk is used for partitioning. --Optichan 22:56, 22 February 2006 (UTC)
- Ah, sorry. In Windows, each of your drive letters (C:, D:, etc) is a different logical partition of your hard drive(s). Depending on how you've wiped your system, those partitions may no longer exist, though I think it's more likely that they are formatted in NTFS, which doesn't play so well with Linux.
- So what you need to do is use the fdisk utility to make your drives non-NTFS. (You need a win98 boot disk or CD.) The first extlink on fdisk tells you how to use it. You'll need to delete the existing partitions and make new ones. That page says to split each drive into several partitions, but I don't think that's necessary. fdisk has a pseudo-gui, so you should be able to figure it out; and since your drives are blank, there's nothing to mess up. Hopefully after doing that, Puppy will let you install to disk. It will probably offer to convert the partition to Linux format, which is recommended. - mako 23:49, 22 February 2006 (UTC)
- Could I use a Windows XP disk for that? I have one of those available, a 98 disk may be harder to get. The ThinkPad does not have a floppy drive. Thanks a ton for all your help so far!!!
- The boot CD (a boot disk gets you into a command line interface) in the link above should be fine -- it's just like a boot floppy. You can also use the WinXP disk's recovery console, but the utility is different, it's called diskpart. If you go that route, make sure your partitions are FAT16 or FAT32, not NTFS (it will probably ask). - mako 05:55, 23 February 2006 (UTC)
You are going on the path to the Dark Side, young apprentice. Use an install cd. --Zeizmic 14:34, 23 February 2006 (UTC)
Preview popup for webpages
editI really like the popup feature I have on wikipedia that allows me to preview the articles behind links by mousing-over them. In fact, I'm so used to it that I often find myself mousing-over links on regular web pages, expecting to see a preview of the linked page. Is there an actual way to do this? Obviously, I see the difficulty inherent in the non-standard way that webpages are designed, but was wondering whether such a tool had been created for any browser. Thanks! — Asbestos | Talk (RFC) 18:01, 22 February 2006 (UTC)
- The links should be visible if you've turned them on under "options". What browser are you using? --Shantavira 18:41, 22 February 2006 (UTC)
- I think what Asbestos was asking about is whether there exists a utility like the Wikipedia popups utility (which displays a preview of the linked page when you mouseover a link) for the general internet. I'm afraid I don't know of any, but maybe one of the real internet buffs can help you... — QuantumEleven | (talk) 08:46, 23 February 2006 (UTC)
- If you use Firefox, there's got to be an extension available which allows you to do something like this. And if there's not, well, you can always try to make one :) I'm sure it's possible, though. -- Daverocks (talk) 11:17, 23 February 2006 (UTC)
- In Opera, you can easily make a UserJS of it. ? ?i?ff?? 15:05, 23 February 2006 (UTC)
- On a slightly separate note, I've seen some webpages implement this "preview" strategy on mouse-over, such as articles at ESPN.com. EWS23 | (Leave me a message!) 21:40, 23 February 2006 (UTC)
- Netflix also uses DHTML popups. However, the inherent difficulty is the non-standard format of web pages. It's hard (impossible?) to parse out the right data for every one. Superm401 - Talk 23:33, 24 February 2006 (UTC)
Oscillatoria princeps
editHow are pigments in the cyanobacterium Oscillatoria princeps distributed - by this I mean are they localized in one place or distributed quite equally? -165.161.3.12
- The pigments look sorta even in the Google image search pictures, though some of them have stripe-like things (where the cell membranes meet?). Is this part of a lab assignment where you looked at them? --AySz88^-^
Setting up home networking on win 2000 / os x
editI have a Win 2k desktop that I want to use as a wireless file / print server. I have a wireless router set up for internet sharing. I have an OS X apple laptop, and my so has a winxp laptop. Where can I find resources on how to set up the win2k machine to share files and printers for the other two machines? Thanks!
- Ha! You will find that the monopolies do not like to talk to each other. As well, the best and cheapest printers only like windows-xp. I eventually got a tiny ethernet printserver, but there is no driver for Linux for my new colour laserprinter! If I wasn't so darn cheap, I'd get a fancy colour laserprinter with Postscript and built-in ethernet printserver. --Zeizmic 21:12, 22 February 2006 (UTC)
Thank you - I have os x and 2k / xp drivers for my printer, and I can use all the peripherals I want to network on both machines. It's just the sharing that is bemusing me - I've never set it up before. Any hints? Thanks!
- File sharing is easy from Windows 2000 to Mac OS X. You would first share the files from Windows. It may be as simple as right click on a folder, select Sharing. Mounting on Windows is simple too, just go to My Network Places. It's possible that you need to turn on some Windows properties before sharing works. Then you have to mount it in the Mac. Choose connect to server in Finder, and type smb://windowsname/sharename Notinasnaid 23:12, 22 February 2006 (UTC)
- Right, ooh, this is a complicated one. But it will work, with a little fiddling. Basically, set up file sharing in Windows and OS X: you'll find guides in their respective Helps on how to do this, as well as the Internet. OS X needs Windows File Sharing turned on in "Sharing" in the settings. The Windows and Mac will need to be in the same workgroup (on Mac OS X this is called "Location" in the Network settings). Finally, you'll need to set up your router to do port forwarding. I'm not sure how exactly to set it up, but you'll need these ports forwarded: 137 to 139, 427, and 548. On my router I basically have all these ports set to both TCP and UDP forwarded to both computers. You sound like you have enough experience to do this, but I'm afraid that my instructions are a little hazy. So go ahead and see how far you get, report back and I'll try to work out why it isn't working, if it isn't working. Sum0 23:19, 22 February 2006 (UTC)
- Thank you - I'm afraid I don't know anything about port forwarding - how do I do this? I have a lynksis router.
I have mixed experience with Samba, but let us know if this works. --Zeizmic 00:42, 23 February 2006 (UTC)
- Thanks! OK, I have things set up, and I can see the workgroup on OSX. I use finder to try to log on, but it keeps telling me the password is wrong. I am sure that it is not, because I just set it up on the other machine. Any clues? Thanks!
- Check the username as well; it probably won't be right as it is offered. Make sure to match upper/lower case. Confirm the password works on Windows by logging in as that user. Notinasnaid 10:53, 23 February 2006 (UTC)
Passwords are where I started to have my first trouble, then ms kept putting in new 'security' that kept screwing it up, then my Samba machine would take over as master browser, and the ms machines would barf. --Zeizmic 12:47, 23 February 2006 (UTC)
- The usernames are correct, but the windows machine will not accept them from the mac. Any clues? Thanks!
Reaction between Ammonia-Propylene
editPl let me know the reaction details of Propylene and ammonia in presence of air and Molybdenum based catalyst in Fluid Bed Reactor. The reaction is exothermic and generates Acrylonitrile-Acetonitrile and Hydrocyanic acid as products.
Pl let me know Rate and Order of reaction w.r. to components and also temperature and pressure effects on the reaction.
You can mail me at (email deleted)
Thanks and regards Suryaprakash Digavalli --220.224.24.239 21:25, 22 February 2006 (UTC)
- Pl let me know the chance in 1 million that this guy is actually going to come back to check for an answer. freshgavinG??? 05:01, 23 February 2006 (UTC)
Biology -DNA
editin terms of an everyday metric unit about how long would be the dna from a single human cell if the dna from all its chromosomes were placed end to end. Please send me in my e-mail address today. Email removed to avoid spam
- Did you read our article on DNA? We have a section specifically addressing the average length in humans. — Lomn Talk 22:49, 22 February 2006 (UTC)
February 23
editNewton's gravitational force equation
editI have been asked how much larger or smaller the Sun's gravitational force is on Jupiter than the Sun's gravitational force on Earth, given that Jupiter is 300 times more massive than the Earth and 5 times as far away from the Sun. Here's what I did:
(G*M*m) / r^2 = x * (G*M*300m) / (5r)^2
(G*M*m) / r^2 = x * (G*M*300m) / 25r^2
Cross out a bunch of stuff
x = 25/300 = 1/12 so the Sun's gravitational force on Jupiter is 1/12 of that on Earth.
M is the mass of the Sun, m is the mass of Earth, and r is the Earth's distance from the sun.
Correct? Thanks. 128.119.59.7 00:42, 23 February 2006 (UTC)
- You say "so the Sun's gravitational force on Jupiter is 1/12 of that on Earth."
Say instead 'so the Sun's gravitational force on Earth is 1/12 of that on Jupiter.'
However, make sure you read the question correctly. Does it ask for the Sun's gravitational FIELD at the locations of Earth and Jupiter? That would be independent of the planet mass, ie. GM/r^2 and GM/(5r)^2 GangofOne 01:05, 23 February 2006 (UTC)
- actually, he was right the first time - according to his calculations, the Sun's gravitational force on Jupiter would be 1/12 that of its force on Earth. But there is something a little odd about those calculations, since he's made 25*25 = 300, and made the Earth's distance from the Sun equal to five times the Eart's distance from the Sun! What you should have is
- (G*M*m) / xr^2
- where m is the planet's mass and r is the distance from the Earth to the Sun. For the Earth, x = 1. For Jupiter, x = 5.2, since it averages 5.2 AU from the sun. G and M are constants, so can be ignored. If you're asking about the gravitational field, then you can ignore m as well, as GangofOne says, leaving a figure of 1: (5.2)^2 or 1:27.04 - i.e., the field is 27 times as strong here to at the orbit of Jupiter. For the force, though, you've got to calculate in that Jupiter has 317.89 times the mass of the Earth, so the force would be 317.89/27.04 = 11.76 times as strong at Jupiter. (can someone please check my maths? :) Grutness...wha? 06:03, 23 February 2006 (UTC)
- Your math looks cherry to me, Grutness :) I did the calculation and came to the same result. — QuantumEleven | (talk) 08:43, 23 February 2006 (UTC)
- Yeah, I think that's right. The force is about 12 times as strong on Jupiter.. I should have put x on the other side. This is for an intro class, that's why he gave approximate values for the distance and mass of Jupiter. Thanks everyone! 128.119.135.190 15:19, 23 February 2006 (UTC)
- Your math looks cherry to me, Grutness :) I did the calculation and came to the same result. — QuantumEleven | (talk) 08:43, 23 February 2006 (UTC)
Active Chromatin Sequences And DNaseI Hypersensitivity Sites
editI'm struggling to understand ACSs and HSs. What exactly is the relation between the two? If 30% of HSs are ACS, then what are the other 70%? If the histones are configured in such a way as to expose a section of DNA, then surely the chromatin sequence is active? There's so little information available on the internet, it isn't funny. --Username132 01:48, 23 February 2006 (UTC)
Magnesium Prices
editHey there. I need to find out how much 1 US pound of magnesium metal would cost for my chemistry class and I'm having trouble finding it. Any help? Thanks --Chris 04:37, 23 February 2006 (UTC)
- Just clicking around a bit I found this page, [2], although you'll have to create a login to see the prices. freshgavinG??? 05:09, 23 February 2006 (UTC)
- Here's another article: [3]. It looks like pure magnesium runs about $1.30 per pound in bulk. It will cost you more than that if you're looking for high purity or for small quantities, of course. TenOfAllTrades(talk) 05:19, 23 February 2006 (UTC)
- Also, shipping tends to be expensive for hazardous materials. Notinasnaid 12:32, 23 February 2006 (UTC)
- All that being said, I wonder what a US pound is. freshgavinG??? 12:39, 23 February 2006 (UTC)
When I was a young, disturbed lad, I used to play with magnesium ribbon. Boy, was that stuff neat! --Zeizmic 12:49, 23 February 2006 (UTC)
Hmmm...I did find a site http://www.chemicalstore.com/ that is selling 30g of magnesium ribbon for $15, making it almost $270 a pound, yet a website above says the commercial price is more like $2 a pound. Interesting. I'll keep looking into it. Thanks guys.
Statical Mechanics
edit- I see that they are not the same. Because of hv/ (e{hv/ kT}-1) do not need to set somewhat coeffiecients, even in this case.
And setting somewhat numbers does not respect Planck.
The official method, is to be the 2nd I wrote before.--HydrogenSu 15:28, 23 February 2006 (UTC)
I know that planck's:
???? ????? :
mulitiplied by 1/n then do another parts of statics. Then do N*n backing to the original formulas
?*1/??, ??????????? ??[???*??]?????
(??=dimension)
??????!!!!!!!!!!!!!!
?????????????????????Same or not between these two cases?
note:for 3D
-
- .
- .
- .
- .
- .
- .
........then others
Between
.......then others in Math.....
- .
- .
- .
- .
- .
- .
The same or Not?--HydrogenSu 13:14, 23 February 2006 (UTC)
Sorry my English is not good. So in Chinese above for my Q. of Planck's.--HydrogenSu 13:03, 23 February 2006 (UTC)
- Please, don't post exclusively in Chinese. This is, afterall, the English reference desk. ? ?i?ff?? 13:23, 23 February 2006 (UTC)
- Yes indeed. Please try zh:Wikipedia:?? or perhaps fr:Wikipédia:Oracle if you want to write in French. —Keenan Pepper 14:08, 23 February 2006 (UTC)
I see that you're back. --Zeizmic 13:35, 23 February 2006 (UTC)
- I can read written chinese and am well versed in quantum mechanics, yet I still have no idea what you're asking, in fact, your questions don't really make any sense--205.188.116.74 05:07, 24 February 2006 (UTC)
New WiLL / DECT technology
editIs there any device (or any kind of device) which, if we keep it at our home, will help us take a cordless phone up to 10 kilometres from the point that device is placed. Is there any such Wireless in local loop technology or any dect technology? I saw it in a TV show but forgot its name.
- This is a nice essay on phones. [4] I tend to agree with them that there is a lot of misleading advertising, and some 'black market' phones may be illegal. --Zeizmic 17:09, 23 February 2006 (UTC)
can anyone say why extra long range cordless phones are illegal in USA
- In some cases, they may be illegal because they're exceeding the permitted power or range for that frequency. Some frequencies (like those for cordless phones and for wifi and the like) have specific power restrictions, to ensure that it's usable by more users in an area than if a greater power was allowed. This is coordinated by the FCC. kmccoy (talk) 21:23, 23 February 2006 (UTC)
We definitely need to increase cordless phone range so we can go from just dozens of people who can listen in on your calls to thousands. :-) StuRat 02:57, 24 February 2006 (UTC)
RNA Nitrogen Bases
editHello, My name is Dalas Gade and I am a Grade 12 Biology student. I asked my teacher a question today that he was not able to answer and I was wondering if you possibly could. I was wondering where mRNA gets its nitrogen bases(guanine, cytosine, adenine, and uracil) from? Does it go into the nucleus already having them? or does it get them from an area inside the nucleus? I hope you will be able to answer this question, and I thank-you in advance for the info.
Dallas
Ut gets them from the cytoplasm, there's specific details somewhere in an article I will dig up, but there will be loose bases hanging around in the cytoplasm which it picks up. They are synthesised in the cytoplasm itself, and I guess they hang around in the cytoplasmic fluid until it is picked up, and if I recall correctly, mainly passive transport is involved; active transport may assist somewhat. Given that, these bases are easy to form in nature outside a cytoplasm too, given the right conditions (one of the theories for the origin of life, ie. five hydrogen cyanide molecules can polymerise to form adenine. Elle vécut heureuse à jamais (Be eudaimonic!) 18:35, 23 February 2006 (UTC)
- What I don't know about biology could fill a book! But I just entered 'messenger rna' in the magic answer box to the left and got a fascinating article that told me all about the creation and destruction of mRNA. It's so neat! It's almost like this is an encyclopedia! --Zeizmic 18:38, 23 February 2006 (UTC)
- If you knew more about biology, you might have actually understood that the Messenger RNA article does not answer his question. Nor does the nucleotide article, although that's a bit closer. It's almost like this is an encyclopedia, not a magic answer box. Chuck 19:32, 23 February 2006 (UTC)
oooh, but I did learn from the nice simple picture, that mRNA is created from scratch inside the nucleus, and then picks up the bricks for building proteins outside. Let's wait for a response (10% chance), shall we? --Zeizmic 21:06, 23 February 2006 (UTC)
- Actually, the mRNA is assembled from nucleotide bases inside the nucleus. The bases themselves–which is what the original question was about–can come from a few different sources. There are several salvage pathways at work within the cell that permit the cell to chop used mRNA back up into mononucleotides (single bases) for reuse. There are also de novo synthesis pathways that allow a cell to create new bases from scratch (amino acids and ATP, mostly), albeit at a relatively high energy cost. The salvage and sythesis pathways both happen outside the nucleus, as far as I know; the bases then diffuse into the nucleus. TenOfAllTrades(talk) 22:02, 23 February 2006 (UTC)
The voltage drop in a long electric arc
editWhen a current is flowing through a plasma in sufficient strengh to make an arc, say 2000 amps, what is the voltage drop? Does the voltage drop increase if the arc gets longer, as in a distance increase between the anode and cathode. From what I know most of the voltage drop in a plasma arc comes from anode and cathode resistance so does this mean that the length of the arc isn't really important? Thanks a lot, cc -- 24.137.78.34 20:25, 23 February 2006 (UTC)
- Conduct this really neat experiment [5] and measure the current as you pull apart the pencil leads. --Zeizmic 22:20, 23 February 2006 (UTC)
- That is a neat experiment. But does anyone know what an "electric fire" is? (BrE, I assume.) We've got an article on it, but it redirects to HVAC, with no clue. —Steve Summit (talk) 00:15, 24 February 2006 (UTC)
- "Electric fire" is British English for a portable electric heater, or one that you would install in a fireplace to simulate a fire. --Anonymous, 00:30 UTC, February 24, 2006.
Why do coaxial splitters lose signal?
editSomething I don't understand about coax cable. If you have a splitter, I've been told you lose signal at each port, even if nothing is connected to some of the ports. This defies what I thought I knew about electricity. I thought open circuits don't use power. Can someone explain this or give a link where I can learn about it? Thanks --Duozmo 22:35, 23 February 2006 (UTC)
- Reflections? --cesarb 23:14, 23 February 2006 (UTC)
- Thought I can't provide a fully scientific explaination, I can give you my idea. Theoretically, electricity should not be able to travelle along a wire as long as the wire is conductive. This is true, but to only a certain extent. When dealing with complex electrical signals, ones that are supposed to carry a specific pattern of signals, then there is a possibility that the patterns could be corrupted at some point, especially if they are being split and sent in different directions. Though the electricity should follow through the wires perfectly, it doesn't, because the universe is in no way perfect.
- I do hope someone else can provide a more technical explaination.
- See coaxial cable. There is a hell of a lot of magnetic interference in a coaxial cable. If the cable is in a perfectly straight line with good shielding and no metal nearby, you will get a great signal. With every bend, break in the shielding, joint, or nearby mass metal, you mess with the magnetic field. That impedes the signal. So, if you have a splitter with no cable on one of the splits (using it as an end-to-end connector), you will get signal loss due to the impedance created by the bend, shielding loss, metal casing, and so on. --Kainaw (talk) 00:54, 24 February 2006 (UTC)
- Well the energy obviously has to split between the branches. Given its a high frequency system where matching characteristic impedance is pretty vital this means the voltage has to split too. This can be achived either using resistors (cheap splitters) or other less lossy means (more expensive splittlers).
It might be useful to visualize an analogy with a similar system of water pipes. A place where the pipe splits will slow down the flow, even if all but one pipe are sealed. You will get water sloshing in and out of the dead end pipes, causing turbulence, and otherwise using up energy. StuRat 02:46, 24 February 2006 (UTC)
- Yes, the answer is "reflections", and this is stated in the article that the questioner referred to. To learn more, I suggest you read impedance matching. In short, unterminated ports cause reflections that bounce up and down the cable until they are absorbed by resistance somewhere. Terminated ports soak up the energy before it can be reflected. The energy loss in both situations is the same, but in the open port case the reflected signals cause noise (in other words, a reduction in the signal-to-noise ratio). --Heron 20:32, 24 February 2006 (UTC)
- Thanks for the answer Heron. I did indeed see the "explanation" at the end of that page and tried to understand it before posting this question. I would actually describe that as a statement of results, rather than an explanation of how they happen. I will check out impedance matching. Thanks again. --Duozmo 00:33, 25 February 2006 (UTC)
- Good luck. I've just looked at that article, and it's not very user-friendly. If you still don't understand, then ask some questions on the discussion page there and I or someone else will try to help. --Heron 20:56, 26 February 2006 (UTC)
Mod Podge
editWhat is Mod Podge made out of?
It doesn't say on the label, or the Plaid website. Other websites tell you to refer to the label. "Non-toxic" and "waterbased" are all the label says.
- I don't know the ingrediants but my best guess is that they are similar to those in regular white glue. Like white glue, Mod Podge dries clear and is water-based. Perhaps Mod Podge has white glue as a base and a water based glaze is added to it in order to give the Mod Podge its viscosity and to give the projects a glaze type effect. - 67.70.155.26 02:40, 24 February 2006 (UTC)
- Not sure how helpful this is, but I found (via Google search) several sets o' instructions for "home-made Mod Podge". The one I liked best is here; to quote: "Homemade Mod Podge: Mix 1 cup of white glue with 1/3 cup water. Add 2 tablespoons of varnish for gloss finish. Keep in a container with a tightly sealed screw on lid. Use for decoupage projects." The addition of varnish distinguishes it from the mass o' recipes which tell you to thin white glue with water—1:1, 2:1 (various are given). —Martha (talk) 22:45, 29 January 2010 (UTC)
February 24
editfeelings
editWhy or how do we feel emotional?
- Emotion? What a peculiar concept... So, did you see our article on emotions already? Also, note that the definitions of emotion and feelings are different. ? ?i?ff?? 07:34, 24 February 2006 (UTC)
Transmission and distribution
editwhy do we earth the neutral wire taking all the neutral wires from our homes near the transformer? what will happen if we ground the neutral wire in our home? thank you for your love and support
- This is all done for safety. If you do anything wrong, the system will probably keep working, but may be unsafe: you or your family are more likely to die if a fault occurs later. See Ground (electricity): on no account touch anything unless you do understand the difference between the purpose of ground and neutral. Notinasnaid 08:22, 24 February 2006 (UTC)
STretch MArks
editi read on the stretch marks article that cocoa butter helps fade & flatten the marks. Does it really work? thks
- As the cosmetics makers would say "it reduces the appearance of stretch marks". That is, it doesn't make any permanent change, but does fill in low spots and smooth out rough edges, while it remains on the skin. StuRat 10:57, 24 February 2006 (UTC)
- The latest wording I've seen reads "can reduce the appearance of", so can is an additional qualifier, and reduce is hopelessly open to interpretation. Imagine if all products were advertised this way - say you were considering buying a Volvo S50, and the advertising tagline read "The New Volvo S50: 8 out of 10 owners who expressed a preference said they thought it might reduce the appearance of you being broken down in a layby on the A66". -- Finlay McWalter | Talk 00:32, 25 February 2006 (UTC)
MP3
editA compact disc previously was able to store only about 15 to 20 5-minute-audio files. But these files have been converted to MP3 format to store large amount of information within a limited space? What technique is used for the conversion of ordinary audio files to MP3 files. I heard that something is being eliminated and the audio file is compressed. What is being eliminated? Please explain this process in detail. Thank you.
- If you really want a detailed explanation, then you should read Audio_data_compression#Lossy_compression. Basically, yes, some of the information is eliminated. How much information is lost depends on the bitrate used, but it tends to be those bits which you won't notice losing, such as frequencies too high or low for the human ear to pick up. Most people can't tell the difference between a bitrate of 128 (or higher) and the source. Markyour words 11:51, 24 February 2006 (UTC)
- It's safe to say that most (about 90%) of the information is eliminated. The algorithm is very complex, and really built around the human ear, similar to TV (RGB) being built for the human eye. To another species, with a different ear blueprint, MP3 wouldn't necessarily sound nice at all :) dab (ᛏ) 11:58, 24 February 2006 (UTC)
- It's not quite that much. The file is compressed to about 10% of its original size (assuming CD at about 1400 and mp3 at 128), but a lot of that compression is lossless. IIRC, a 128 bit file has about 2/3 of the original information. Markyour words 13:10, 24 February 2006 (UTC)
Leaving the question of why the original cd specification did not include (lossless) compression.
- Because uncompressing the file requires a fair amount of processing power, which your average stereo in 1980something didn't have. (Even today, using lossless files on your iPod uses so much processing power that the battery life is reduced rather drastically). Markyour words 20:57, 24 February 2006 (UTC)
- I doubt that lossless codecs are necessarily more computationally intensive. It's likely that the drop in battery life is due to the fact that the bitrate is almost always higher with lossless compression; this means that the iPod's hard drive has to spin up more frequently, draining the battery faster. I had an MP3 CD player that lasted about 5 times as long playing MP3s as it did with regular CDs, and MP3 is certainly the harder format to decode.
- Not to mention, the higher bitrate means a given storage medium can't hold as much music with a lossless codec. —David Wahler (talk) 03:39, 25 February 2006 (UTC)
How does Google do it?
editI notice that yesterday Google launched their newest feature, Google Pages, which allows users to have up to 100mb of free webspace. While I haven't been able to trial it yet, it seems like they don't put advertisements on the webpages they are hosting. The same is true with Blogger? Why do they provide these services for free with no advertisements? They are a publically listed company - surely to offer a service like this there must be some way of making money from it? What commercial advantage do they gain from offering these services? --TomPhil 12:40, 24 February 2006 (UTC)
- I don't know about "Google Pages," but I think most of the Google products have text advertisements based on search results from the page. This is how Gmail operates. Since Google has a ton of hits, I'm sure these small text advertisements are pretty desirable. EWS23 | (Leave me a message!) 19:19, 24 February 2006 (UTC)
Where does Google do it? I can't find it. For one it's not listed in http://www.google.com/intl/en/options/. DirkvdM 12:57, 25 February 2006 (UTC)
- https://www.google.com/accounts/ServiceLogin?service=pages&continue=http%3A%2F%2Fpages.google.com%2F Markyour words 16:03, 25 February 2006 (UTC)
- http://www.googlepages.com. But they do the same with Blogger; they removed the text based advertisements of blogs months ago. --TomPhil 16:44, 25 February 2006 (UTC)
- They encourage you to make pages, then encourage you to stick the advertisements yourself voluntarily, giving you a cut. This way, the people with the pages gets money, Google gets love and PR status, etc. etc. Elle vécut heureuse à jamais (Be eudaimonic!) 02:56, 3 March 2006 (UTC)
google restrictions
editshoudnt there be restrictions in google as it allows anyone(including terrorists)to access the exact location of a place through satellite images?thanks,
rhinsa
- There are several schools of thought on this issue, but concern about terrorism is probably overblown—terrorists don't want to attack out-of-the-way secret military bases or highly secured civilian installations (like nuclear power plants). Terrorists generally prefer to attack soft targets that are visible to lots of people. The goal of terrorism is to instill fear, not necessarily to directly achieve military or strategic goals.
- The World Trade Center, for example, was attacked on two separate occasions. Subway systems are a popular target as well. In general, the location of any target likely to be of interest to terrorists is already very well known; Google Maps and Google Satellite don't add anything that can't be found in a tourist guidebook. TenOfAllTrades(talk) 13:53, 24 February 2006 (UTC)
- Before Google Earth, there were many just-as-effective ways of finding out where stuff was, such as paper maps and atlases, and these still work just as well today, so 'restricting' Google would have no impact.
- Additionally, if someone were to be thinking about attacking a major facility, the exact location would be much less important than the local conditions, design, structural weaknesses, security arrangements etc etc. And these you can't get all from Google - you'd most likely need to go there and 'scout' the area.
- Finally, slightly off topic, but it can be argued that terrorists are incredibly ineffective in causing actual damage - the chances of you dying in a terrorist attack is comparable to the chances of you being killed by a meteorite, ie almost nil. Terrorists work by spreading fear and causing a population to become paranoid of future attacks, and instigate measures such as restricting the free flow of information (eg your idea), a reaction that is ultimately pointless and hurts yourself much more than it hurts the terrorists' operations.
That hasn't stopped certain paranoid members of the US government reducing the resolution of released satellite images of certain 'important' landmarks in the US, such as the White House. Try looking up central Washington DC on Google Earth - you'll see that certain areas are only available in lower resolution...(see below) — QuantumEleven | (talk) 14:24, 24 February 2006 (UTC)
- Which "certain areas" are those? Have you looked lately? —Steve Summit (talk) 18:07, 24 February 2006 (UTC)
- Huh... you're right! I've just gotten home from work and checked... there isn't a reduction of detail on Google Maps at all. So I take back what I said - I seem to recall that it was once the case, however, I have no evidence at hand to back that up, and it certainly doesn't seem to be the case anymore. Sorry for not checking up before. — QuantumEleven | (talk) 18:28, 24 February 2006 (UTC)
- No prob; I was just teasing. You're right, it is strange (and no, you're not crazy). As recently as last December, in Google Maps, the White House had a featureless gray roof and the U.S. Capitol was pixellated. But Google Earth showed both of them unmodified, and at higher resolution, to boot. Then, some time in January I think, Google Maps started hitting the same higher-res dataset that Google Earth uses, and so both of those landmarks became fully visible in Google Maps as well. —Steve Summit (talk) 22:45, 24 February 2006 (UTC)
- The USNO is one example. --BluePlatypus 20:45, 24 February 2006 (UTC)
- That's odd - I wonder why they blanked that and not the Pentagon or the White House. That seems a bit random. Anyone else find any other places that have been blanked...? — QuantumEleven | (talk) 21:29, 24 February 2006 (UTC)
- There was a big to-do a month or so ago when it was requested that the neighborhood containing both Dich Cheney's and Donald Rumsfeld's houses be obscured. I don't know where that is, so I can't check. —Steve Summit (talk) 22:45, 24 February 2006 (UTC)
- Yup, the Vice Pres lives on the USNO grounds. I didn't know he was bunking with Rumsfeld though. :) --BluePlatypus 02:16, 25 February 2006 (UTC)
- There was a big to-do a month or so ago when it was requested that the neighborhood containing both Dich Cheney's and Donald Rumsfeld's houses be obscured. I don't know where that is, so I can't check. —Steve Summit (talk) 22:45, 24 February 2006 (UTC)
- Some governments have complained that the satellite imagery gave away too many structural details about certain government buildings, and Google has occasionally blocked out certain buildings (the White House, for example, used to be colored over with solid pixels, so you couldn't see the details. It no longer seems to be, though, in either Google Earth or Maps). I recall India apparently made a fuss of this not too long ago. But I think most people -- Google included -- agree that these sorts of things would be of limited use to terrorists. And in any event, satellite imagery via computers has been around a lot longer than Google has been (I remember using Microsoft's Terraserver back in the day, and feeling an immense sense of power that I could zoom in on the Pentagon. The power was illusory, of course, but what an illusion!). --Fastfission 17:08, 24 February 2006 (UTC)
- For a while, Google Maps blanked out the White House and Capitol. Now, the White House and Capitol show up fine, but the vice-presidential mansion on Massachusetts Avenue is pixellated for some reason -- Mwalcoff 01:55, 2 March 2006 (UTC)
electro-technology s1
editcan you show me electro-technology mathematical formulars
- I've always been fond of - the resistance of an object placed in an electrical socket is proportional to the IQ of the person who put it in. Confusing Manifestation 12:01, 25 February 2006 (UTC)
Simulation Models
editDefine with examples:
- 1-Static Model
- 2-Dynamic Model
- 3-Deterministic Model
- 4-Stochastic Model
- 5-Discrete Model
- 6-Continuous Model
Thanks
Yasmeen Hashish
- A static model is you sitting at your desk not doing your homework. A dynamic model is you pacing up and down the room not doing your homework. A deterministic model is the large keg of beer which will certainly prevent you doing your homework. A stochastic model is a whole room full of clones of you who, each on their own, decide not to do their homework. A discrete model is your homework cut up into little pieces. A continuous model is the large, blank sheet of paper on which you have failed to do your homework. — QuantumEleven | (talk) 13:46, 24 February 2006 (UTC)
- *clap clap clap* ? ?i?ff?? 14:08, 24 February 2006 (UTC)
- Hmm...Perhaps a more earnest response here is warranted. This reads like an introductory homework question, probably in an undergraudate signals and systems course. The point of this question is for you to appreciate the different types of models that are used, how they are related, and the sort of "bipartite partitioning" (my terminology) that is used in the engineering approach to understand and solve these sorts of problems. Note how the systems are interrelated via the groups (1,2) (3,4) (5,6) - In the first group, the contrast is between static (time independent) and dynamic (time dependent). In static models, say, in mechanical engineering, you tend also to work with components which are rigid bodies, which do not change over time. In the second group, the consideration is randomness. Deterministic systems are not random. A stochastic system is random. (A stock market can be modelled as a stochastic system, but it need not be one.) Extremely important for understanding signal processing, cellphones, wireless networks, systems analysis, controls engineering, et cetera. Finaly, in the last group, it is a bit subtle and tricky. A discrete system is something that evolves in steps - the variable of interest (such as time) is not continuous. Anything that involves sampling can be thought of as a discrete system. Computers are discrete. Discrete systems can be approximations to continuous systems - although a discrete system need not be a sampled continuous system. Extremely important to understand much of today's "revolution" in technology. Data compression, security...all in the domain of digital systems. By the way, you will very likely encounter things like Laplace transforms, Fourier transforms, z-transforms, Hilbert transforms, and the like...learn these well the first time around (and extremely well for that matter), because if you don't, it will be very difficult to appreciate any of the really interesting stuff that can be understood with these things. --HappyCamper 19:59, 24 February 2006 (UTC)
Electricity
editYes, electricity is a very current topic...
<flame> Which part of "the reference desk is not a search engine?" do you not understand?! </flame> — QuantumEleven | (talk) 14:44, 24 February 2006 (UTC)
Removed pointless insulting - sorry about that, I had a moment of needing to vent. In any case, you can find articles on Wikipedia much more easily by typing into the search box (in the left margin, halfway down the first screen) and clicking "Search". Have fun using Wikipedia! — QuantumEleven | (talk) 14:55, 24 February 2006 (UTC)
Best way to deal with static HTML sites
editI'm creating a small website for a small, academic client who 1. needs to pages to be static HTML (nothing server-side), 2. needs to be able to update them easily with a minimal of HTML knowledge or technical ability. I'm worried that even WSWG editors are going to be a little on the daunting side for the assistant when they occasionally need to create new pages and edit existing ones. Of course simplifying the design will help to some degree, but beyond that, I'm not complete sure which way to take this.
What's the best way to approach this as a long-term solution? The two ways I've been thinking about this have been to set up some sort of template-driven system in one of the WSIWG editors that they have, though I am not familiar with the options here and how reliable they are. The other is to look into something like CSS/XML which will allow the content to be better separated from the design elements. I'm not very familiar with this, but I could learn it if it was a good solution to problems like this. In an ideal world, I would probably use a server-side content-management system, but getting permissions to run server-side scripts will be more trouble than it is worth in this case (fascist web admins).
Does anybody have any thoughts on the best approach to a problem like this? It has come up before for me, in creating sites for places with very low long-term technical abilities, and I haven't yet come across a great way to deal with it. I'm curious what others do, what I have overlooked. --Fastfission 18:18, 24 February 2006 (UTC)
- A really good idea -- and please understand I'm not saying this just because we're sitting here on Wikipedia's reference desk, but rather because I think it's a really good idea -- is to have an Edit button on every page. Even for computer-savvy users, the distinction between the-view-of-the-web-pages-that-the-end-user-sees-with-their-browser-over-here versus the-HTML-pages-that-we-edit-using-special-tools-on-the-server-over-there can be a surprisingly taxing distinction. It's remarkably easy to forget where the server is or how to log into it, or to forget where the HTML documents directory is or what's needed to edit the files there, etc.
- Obviously you wouldn't want the Edit button to be usable -- or even visible -- by every visitor. You could rig it up with a permission scheme such that only visitors browsing from your own intranet were even presented with the Edit button, and then impose some password scheme beyond that.
- I think there are webserver packages that support this sort of thing -- and if there aren't, there should be.
- I think there are also wiki-like schemes which can manage to give you WYSIWYG editing, with no markup to learn.
- —Steve Summit (talk) 19:32, 24 February 2006 (UTC)
- As I said earlier, server-side solutions won't work. A wiki is definitely server-side -- it requires PHP, MySQL, etc., all of which are not feasible in our current setup (I don't have control over this). --Fastfission 01:00, 25 February 2006 (UTC)
- There are many WYSIWYG web-based editors. It isn't hard to write your own. The catch is that WYSIWYG editors produce tons of garbage code. So, you will need to write an HTML Tidy program to clean it up. --Kainaw (talk) 21:01, 24 February 2006 (UTC)
- I know there are many such editors -- the question is which of them would do what I want, or the best way to get what I want out of them. Perhaps I haven't been clear enough about this above? --Fastfission 01:00, 25 February 2006 (UTC)
- A slightly more user-taxing solution would be (as you already mentioned) put as much of the formatting into CSS files and leave the HTML files themselves as much plain text as possible. The person updating the site only needs to learn very rudimentary HTML (paragraph, heading and link tags, as far as I can see), and you can even put comments into your HTML files to show them what they need to edit and what they should leave alone. That way, you don't need any server-side scripting... but the feasibility depends on how knowledgeable your users are, and how often you think you'll get called in because they managed to delete one tag which messes up all the layout. Good luck - this is not an easy problem to solve if you're not allowed to do any server-side scripting (which means no content management system, which would have been the way I would have suggested). — QuantumEleven | (talk) 21:26, 24 February 2006 (UTC)
- Hmm, well that's the difficulty I'm dealing with on this. You'd think there would be some sort of intermediate solution between WSIWYG and full server-side content management. Basically, an ideal system would allow me to set up a WSIWYG template and lock all of the design elements to prevent accidental changing of them. Maybe something like Dreamweaver allows for this? I guess I'll just have to tinker a bit. --Fastfission 01:00, 25 February 2006 (UTC)
- What makes little-to-no sense is that you claim that you want nothing server-side. So, how are changes supposed to be saved? You can have the coolest WYSIWYG editor embedded into a page, but it is nothing by a fancy pile of crap if you can't save the changes on the server side. You must have a stand-alone website editor that just uploads pages via FTP (or something similar). Even then, they are not dummy-proof. If you want to edit web pages, you have to learn something. Also, be very wary of the WYSIWYG editors. Every time you edit a page, it grows. The more you move text around, the more they grow. This week, I cleaned up two WYSIWYG-edited pages. Both contained nothing but 3 short paragraphs and a couple small pictures. The HTML contained over 6,000 characters (which made their editors appear to lock up - which is why I was called in to check it out). If they'd just learn simple HTML (monkeys can learn HTML), then there wouldn't be a problem. --Kainaw (talk) 01:16, 25 February 2006 (UTC)
- Listen, as I said, it isn't up to me whether it is server-side or not; it's simply not possible in this case (the net admins don't allow scripts; even if they did, there would be nobody to maintain them if they needed upgrading or suddenly stopped working). This is not a case of what should be done in an ideal world, but what can be done in these circumstances. Yes, it'd be great if there was someone who would learn a little HTML at the place that I'm making the site for, but in reality it's not going to happen. One thing that web designers often lose sight of is that making something which will work correctly in the long-term is just as important as making something which is technically accurate or elegant. Long-term solutions are often about social circumstances as much as they are about technical ones. --Fastfission 04:16, 26 February 2006 (UTC)
- Macromedia Dreamweaver allows you to create templates that allow you to edit certain regions of the page, while leaving others locked. When you update the template, all the pages based on that template are updated automatically. Dreamweaver also comes with an FTP client with synchronization features, so it's easy to keep the local copy synced with the server copy. Of course, it's not cheap (unless you're a student). enochlau (talk) 00:41, 26 February 2006 (UTC)
- Hmm, that might work out perfectly. I'll have to check but I'm pretty sure the university I'm at has a site license for Dreamweaver. Thanks! --Fastfission 04:16, 26 February 2006 (UTC)
The Human Genome released to Private Businesses
editWhat are the reasons for the Human Genome being released for development to the Private Business sector when governments could do it themselves and everyone would have access to it? Especially considering the government used taxpayers money to fund the Human Genome Project initially.
Thanks for any help. 204.72.116.28 18:22, 24 February 2006 (UTC)
- The question presumes facts that are simply not true. The results of the human genome project are available to anyone. You can go to Project Gutenberg and download text files containing the sequences for all 23 chromosomes. Raul654 21:52, 24 February 2006 (UTC)
- There is a problem about monopoly. Would you like to have one government use all the results and decide that they are no longer available to public because there are spies or terrorists ? But, granting things to private business may lead to a similar risk. It takes time to create a private monopoly, but some (or plenty) have existed.
- You may have the ultimate power to decide if companies do good work and what price you are OK to pay for your health, and also what amount of knowledge about you and your beloved must be guarded from profit. That is, if you are rich enough. --DLL 22:15, 24 February 2006 (UTC)
- See our article on the Human Genome Project. The complete sequence of the human genome is available online, for free, from a number of public sources. Ensembl] provides access to a browsable, annotated copy of at least 25 species' genomes. Per Raul654's comment, access to the HGP's results has by no means been restricted to the private sector. TenOfAllTrades(talk) 22:52, 24 February 2006 (UTC)
I think that the poster has the story just about right, if not the facts. 60 Minutes did a segment on this a while back. And I also remember it from the documentary "The Corporation." It seems that major biotech companies have indeed patented almost all, if not all, of the human genetic sequences, including the exons (not the oil company, but parts of the chromosome previoulsy thought not to be functional).
According to "The Corporation" a documentary I have on DVD, when a company holds a patent on a genome sequence, only that company may profit from research it. The thought is that no one will work on diseases and cures encoded in that sequence if they think they will have to contend with competition.
In the early 1980s, if I remember correctly, a company wanted to patent a geneticly modified bacteria which would basically eat crude oil. This was to clean up oil spills. The US patent office said, "No." It was against the rules to patent a living organism. Whoever wanted to patent this little critter had lots of money and lots of lawyers, and they challenged the US patent office repeatedly, until they finally convinced the court that this bacteria had some properties of living things, but that it was also a product of human technology too, and some how didn't fit the definition of unpatentable life.
A really sinister part of this story is that at the time there was a gag order on the whole thing. Almost no one knew, so who could object?
Well, after the patent office lost, they began to have to patent all sorts of biological matter. And companies began to patent more and more complex life forms. At last year, the only living thing that can't be patented in the US is an individual live-born human infant! -Leah
Rarest earth element?
editWhat is the rarest naturally occurring element on earth?
- Usually considered to be Astatine, but Francium is also a candidate. --BluePlatypus 19:33, 24 February 2006 (UTC)
Sodium Potassium Alloy
editWhere can I purchase a sodium potassium alloy online, that is not on back order?
- I am not sure myself off hand, although I have made some of my own in my lab in small quantities for demonstration purposes. May I ask what you need this for? :-) --HappyCamper 20:02, 24 February 2006 (UTC)
Triple Point
editWhat does the triple point of water look like? Has anybody ever seen it? Is it even possible to reach?
- Yes, it is possible. It just happened in the Olympics. See [6]. --Kainaw (talk) 20:56, 24 February 2006 (UTC)
- Now that's cool. Tip o' the hat ta ya, Kainaw. —Steve Summit (talk) 22:11, 24 February 2006 (UTC)
- A minor nitpick—while water ice's unusual structure (the solid phase is less dense than the liquid) results in a somewhat atypical phase diagram that allows pressure to melt ice into liquid water, the triple point of water doesn't have anything to do with ice skating. The high pressure under an ice skate's blade actually takes us further from the triple point of water.
- Looking through some of the other pages on the linked site, there appear to be several minor (and a few major) errors; I suspect it was a class project of some sort that hasn't been very thoroughly vetted for accuracy.
- In practice, it's certainly possible to reach water's triple point. 6 mbar is a relatively poor vacuum, and 0.01 degrees Celsius isn't hard to maintain. At the triple point, the water won't look like anything special; it will just come to some equilibrium between liquid and solid, surrounded by an invisible, low-pressure water vapour. TenOfAllTrades(talk) 22:42, 24 February 2006 (UTC)
- Check out our article on triple point — QuantumEleven | (talk) 21:20, 24 February 2006 (UTC)
- Note also that temperature units these days are defined in terms of the triple point of water. For example. 0°C is no longer defined as the freezing point of water; instead, the temperature in degrees Celsius is simply defined to be the temperature in kelvins (formerly called degrees Kelvin) minus 273.15 exactly. So 0°C = 273.15 K exactly. And the kelvin is defined so that absolute zero is 0 K and the triple point of water is exactly 273.16 K. The thing is that standards in metrology are chosen to be something that it is practical to reproduce or measure. [Well, almost always; for a while the second was defined as a certain fraction of the year 1900. But one reason this was changed was precisely because the year 1900 was a little :-) difficult to reproduce.] So the choice of the triple point, rather than the freezing point (at some particular pressure), indicates that scientists feel it is practical to produce it exactly. --Anonymous, 23:15 UTC, February 24, 2006.
- That's a cool link at the top of this question,(13) but I'm not sure that it's right. It says "It is the closeness of the triple point temp to the freezing temperature of water that allows just a persons weight over the area of the blades to make use of this property." That may be true, but it doesn't mean that the Triple point is actually reached under an ice skate. In fact it doesn't. The Triple point is at a very precise temperature (just over zero degrees) and if we had to reach it in order for skates to work then skates would only work at that temperature, not a degree lower or higher.
- Even if the closeness of the Triple Point is part of water's unusual properties in this respect, I don't think the triple point is reached while skating. DJ Clayworth 16:28, 27 February 2006 (UTC)
Confusing Chemical Equation
editWhat are the products for this chemical reaction. If someone is able to could they please include a mention of which species is oxidised and which is reduced. If the equation could be balanced as well that would be really good but I really just want to know the products and the oxidised and reduced species: KMnO4 + H2SO4 + FeSO4.7H2O-->?
- This sounds like a homework question, so I can't just give you the answer, but I can help. Find the oxidation states of the metals. The sum of all the oxidation states of a complex ion is equal to its charge, and oxygen is almost always -2. (Or you could just look up the answer at Permanganate.)
- The easiest way to balance any redox equation is to split it into two half-reactions. One should have electrons (e-) on the left side and the other on the right side. Multiply the half-reactions by constants so they have equal numbers of electrons, then add them together. —Keenan Pepper 04:25, 25 February 2006 (UTC)
- As far as predicting the products, you'll need to identify the ions in solution first, and then you can use a table of standard reduction potentials to try to figure out what's likely to be reduced, and what's likely to be oxidized, in the reaction. Chuck 20:18, 27 February 2006 (UTC)
The actual answer isn't on the permanganate page. The question is almost prehistoric in its awfulness, and as a teacher of chemistry, I object to students being set such rubbish. There is absolutely no value in trying to produce a complete, balanced equation for this bog-standard redox titration. The only ions taking part are MnO4- (which is reduced), H+ and Fe2+ (which is oxidised). The products are Mn2+, Fe3+ and H2O. G N Frykman 18:14, 3 March 2006 (UTC)
download an entire website
editare there any plugins to download all files on an entire website?
- wget or curl are a couple of utilities that are excellent for this purpose. wget is included with most unix/linux machines, Mac OS X includes curl, and on windows you can get cygwin and use either. Night Gyr 21:59, 24 February 2006 (UTC)
- And I have to believe there are GUI-based tools for this as well (although as a command line type of guy myself I've never looked). Anybody know of any? —Steve Summit (talk) 22:18, 24 February 2006 (UTC)
- HTTrack is very handy. Maybe too handy. - mako 09:50, 25 February 2006 (UTC)
- Yep, I use it a lot and it's very tweakable. Actually, as they point out, you can download the entire internet with it. You'd need a hefty hd, though. :) DirkvdM 15:02, 25 February 2006 (UTC)
- Is there a generic term for utilities like this? If so, we should have an article on them. I've seen a couple uses of the term "webgrabber", and there's at least one tool by that name, but a google search for "define:webgrabber" gives no hits, and www.webgrabber.com is for something completely different. —Steve Summit (talk) 16:00, 25 February 2006 (UTC)
- Answered my own question again. A google search for "website copier" gives lots and lots of relevant hits. —Steve Summit (talk) 16:05, 25 February 2006 (UTC)
:An easy way to download the Internet. Or [here] --DLL 20:26, 25 February 2006 (UTC)
- The first one has the right presentation to actually make people think something is going on. If they use msWindows, that is. I use Linux and the msWindows download box sort of gives it away. :) DirkvdM 10:54, 26 February 2006 (UTC)
what constellation is the Solar System in?
editIf one were near Sagittarius, near the centre of the Milky Way looking out, what constellation would the Solar System be in? WOuld we recognise the constellation at all? Adambrowne666 23:28, 24 February 2006 (UTC)
- If we were near the centre of the Milky Way galaxy, virtually all of the stars we currently see on Earth would be far too faint to see. In addition, stars near the centre of the Milky Way that are too faint to see from Earth - would be visible. The constellation wouldn't resemble any we see on Earth today. If, instead of travelling all the way to the centre of the galaxy, moved a few light-years - the Sun would appear in the area close to the constellations of Taurus, Gemini, Orion and Auriga. Richard B 23:35, 24 February 2006 (UTC)
- If we were in a different part of the galaxy, wouldn't the constellations as we know them from earth not exist? After all, they are only grouped into constellations because the stars are in a similar part of the sky; the distance between the stars (depth-wise) is huge, and from another angle the stars would be in completely different parts of the night sky. I don't know about the specifics of the stars that make up Sagitarrius, but I would have thought it would be impossible to be "near Sagitarrius" ? -- Chuq 23:40, 24 February 2006 (UTC)
- Which leads one to ask, how far from Earth is a typical "visible" star? (I know visibility is difficult to define, but we can use the conventional threshold of magnitude 6.) --Smack (talk) 23:58, 24 February 2006 (UTC)
- Depends probably more on the definition of "typical". A red dwarf star (by far the most common type of star in the galaxy) - becomes invisible before you're even 1 light-year away from it. The Sun becomes invisible (mag 6) at just over 50 light-years distant. Sirius (brightest star in the night sky as we see from Earth) would become invisible at a distance of around 260 light-years away. Most of the stars in the sky that we can see are actually giant stars - Rigel can be seen up to about 20,000 light-years away. As Chuq says, the constellations as we know them would not exist. It is impossible to be near Saggitarius - but you can certainly move in the direction of Saggitarius - at least until you start going past its brighter stars that make up the general shape of the constellation as we see it. Richard B 00:49, 25 February 2006 (UTC)
Well, getting back to the original question, there's a fun way to answer it:
- Download Celestia.
- Run it.
- In the Display menu, turn on all constellation and star features.
- Using the Location and Direction menus, Go To the Milky Way and then Center Selection on Sol.
- All the constellations will appear as an unrecognizable sea urchin centered around the solar system. I don't know if you can say the Solar System is in any of them.
- Accelerate if you want a closer view.
Melchoir 00:08, 25 February 2006 (UTC)
- Hah! I was just about to suggest downloading Celestia—it's free and excellent! If you name a specific star or point, I can tell you what the sky would look like. Randomly picking a star in Sagittarius (Lambda Sagittarius), we're 77 light-years from Earth. Sol's apparent magnitude would be 6.70; if you could see it, would be in Gemini, probably. The constellations are significantly distorted, but the ones directly opposite Sol are distorted the least. — Knowledge Seeker দ 02:15, 25 February 2006 (UTC)
- Excellent - thanks all of you - I'll download Celestia at the beginning of March, when my broadband kicks in again. Adambrowne666 07:08, 25 February 2006 (UTC)
- (after edit conflict) FWIW, it's relatively easy to calculate what constellation the solar System would be in from other stars, just by taking that star's RA and declination and calculating from that. From distant stars, though, many of the constellations we recognise would be thoroughly distorted because of the varying distances to different parts of them. From our nearest (non-Sun) star system, that of Alpha and Proxima Centauri, the Sun would be in Cassiopeia. Grutness...wha? 07:08, 25 February 2006 (UTC)
- Er, Grutness, while your method works for closer stars, I don't think it works necessarily for more distant stars. How exactly would you go about calculating? As you point out, the constellations get distorted. The standard boundaries between constellations of course gets lost instantly, although one could still attempt to determine which groups of stars were closest. For the example I gave before, with Lambda Sagittarius, my visual inspection shows the sun to be in Gemini, although parts of the Centaurus, Canis Major, and Canis Minor constellations significantly overlap Gemini and come very close. At the other extreme, from Mu Sagittarius, the sun is not visible (apparent magnitude of 16.82), but even if it were, the constellations are all crammed together over the region of Sol; it would be impossible to assign it to a single constellation. From the brightest star in Sagittarius, the alpha star, the sun's apparent magnitude is 8.41 and does not appear to fall within any constellation. — Knowledge Seeker দ 08:20, 25 February 2006 (UTC)
- good points - I had incorrectly parsed what I wrote. The constellation stuff should be referring to close neighbour stars (I did qualify that in the second sentence, but not as well as I should have). Once you get beyond our nearest neighbours, there is a lot of "noise" due to closer stars in (from our view) the same constellation as the star being looked from. If you look back at the sun from Beta Centauri, then it will have Alpha Centrauri in roughly the same general direction, as well as Cassiopeia. From far more distant stars, the picture becomes increasingly messy. But for close stars out to a couple of dozen light-years, say, the distortion shouldn't affect the view so much. From the centre of the galaxy, though, the picture would be too confused to be able to pinpoint any one constellation, since they would all be jumbled together. Grutness...wha? 01:18, 28 February 2006 (UTC)
- Er, Grutness, while your method works for closer stars, I don't think it works necessarily for more distant stars. How exactly would you go about calculating? As you point out, the constellations get distorted. The standard boundaries between constellations of course gets lost instantly, although one could still attempt to determine which groups of stars were closest. For the example I gave before, with Lambda Sagittarius, my visual inspection shows the sun to be in Gemini, although parts of the Centaurus, Canis Major, and Canis Minor constellations significantly overlap Gemini and come very close. At the other extreme, from Mu Sagittarius, the sun is not visible (apparent magnitude of 16.82), but even if it were, the constellations are all crammed together over the region of Sol; it would be impossible to assign it to a single constellation. From the brightest star in Sagittarius, the alpha star, the sun's apparent magnitude is 8.41 and does not appear to fall within any constellation. — Knowledge Seeker দ 08:20, 25 February 2006 (UTC)
-
The first view I mentioned: Sol does appear to be in Gemini, although its nearest neighbors are getting "pulled" in from various constellations
-
From the second scenario, and Sol doesn't appear to really fall within any specific constellation.
-
From the vicinity of the center of the Milky Way: all the stars in all the constellations are crammed together in an "unrecognizable sea urchin" as described by Melchoir above.
- I just uploaded some screenshots (I'll delete them in a week or so). Hope this helps. — Knowledge Seeker দ 08:49, 25 February 2006 (UTC)
Reviving dead humans
editI was wondering what stops someone from reviving a dead human, i am not talking about someone whose heart stops for a while but a confirmed dead patient whose brain activity and heart have both stopped. Is it in any way possible in modern technology or future or simply in theory to revive a dead body which is fullt intact and simply died of system failure or suffocation or something that would not affect the vital organs? 86.129.82.87 23:42, 24 February 2006 (UTC)
- Most of what stops them is that very shortly after death, a tremendous amount of permanent cell damage occurs from decay, lack of oxygen, and so forth. Individual organs can, if recovered after death, be "revived", in a sense — this is why post-mortem organ donation works. But the brain is not one of those organs — the damage it suffers from being without oxygen for only a few minutes is enough to have permanent changes, much less if it has been completely "dead" for any amount of time. --Fastfission 00:52, 25 February 2006 (UTC)
- Hoping to create zombies? Sounds like fun. I assume death usually affects or is affected by something related to the vital organs. Of course, I haven't done any research on the subject. :) --Optichan 15:53, 25 February 2006 (UTC)
- Just save a person's brain data every hour. Then when he dies, throw out the decayed brain and connect a perfect silicium model with the latest data. The model should be functional and evolvable. That will soon be easy. --DLL 19:55, 25 February 2006 (UTC)
- I wouldn't expect it anytime in the next few years. StuRat 21:40, 25 February 2006 (UTC)
- Not to mention we still do not know how information is stored in the brain in the first place, much less how we could attempt to "download" it. -- Rune Welsh | ταλκ 22:29, 25 February 2006 (UTC)
- As long as it has a firewire port you should be able to connect it to any recent mac and boot it in target disk more. Oh, wait...
- Scientists at the Safar Centre for Resuscitation Research in Pittsburgh have been able to revive dogs that had been brain dead for several hours. They replaced their blood with an extremely cold saline solution. The dogs were reported not to have suffered any ill effects (paralysis, brain-eating, etc.). They hope to use the method in extreme trauma cases (war injuries, car accidents) to prevent death by shock before the person can be transported to a hospital and treated. Google "zombie dogs." Seriously. These are some of the same people who invented CPR, so it's conceivable that they could apply it someday.
65.96.184.208 19:45, 2 March 2006 (UTC)
Wikipedia competitors
editWhere can I get a list of other general-reference wikis? I would like to contribute to a project like this, but the political agenda of the Wikimedia Foundation directly opposes my political and religious views, and I can't find a site comparing them. 67.76.161.92 01:47, 3 March 2006 (UTC)
The WMF has an agenda? Or perhaps the policy? I mean, there are things like Wikinfo, but that hasn't taken off too much. Elle vécut heureuse à jamais (Be eudaimonic!) 02:50, 3 March 2006 (UTC)
February 25
editTemperature differences in the earth's atmosphere
editIf heat rises why is it colder upwards (higher) and warmer down below (lower)?
- It's tough for air to absorb light from the Sun (light just passes through it, since it's
invisibletransparent), so the surface gets warmed up faster and then the heat is conducted into the air. After the air near the surface gets warm, then convection causes the warm air to rise a bit. - Just in case: "Heat" doesn't really rise, warm less-dense things are pushed upwards by the sinking of more-dense things. Also, warmer air rises against cooler air and warmer oil rises against cooler oil (lava lamps), but warm water won't rise against cold air due to the density difference, for example.
- Important distinction in thermohaline circulation. Water is less dense when frozen than liquid water below 4 degrees. Elle vécut heureuse à jamais (Be eudaimonic!) 02:52, 3 March 2006 (UTC)
- The article troposphere says: "The reason for the temperature variations in the troposphere is because the temperature is determined by the radiation from the land back into the air. As we move away from the earth's surface, convective heating has a smaller effect and the air cools." It goes on to say that "For every 1000 metre increase in altitude, the temperature goes down by approximately 6.4°C. This is because the higher the altitude, the less atmospheric particles there are to trap the heat, therefore resulting in the heat escaping." (Probably talking about how the Earth loses heat in the nighttime.) --AySz88^-^ 02:03, 25 February 2006 (UTC)
Special Relativity
editDear all, when I read books on Special Relativity, they usually inform the facts briefly, but never go deep into the postulates.
Can anyone explain to me why is their length contraction when things are moving at the speed of light?
Thanks very much!
- The length doesn't contract, it just appears to. It's time that gets dilated in special relativity. Length appears to contract because of the time dilation. Since distance = velocity x time. Suppose you measure the length of a train by measuring the time it takes to pass a person. A person on the train will not measure the same amount of time as the person standing next to the tracks, because they're at different speeds. But they'll agree on the relative speed, so by the equation above, they'll get different lengths. But it's not a postulate (see the article). If you want a guide to S.R., perhaps I can recommend A Brief History of Time? It explains the subject and its consequences at quite a bit of length. --BluePlatypus 02:38, 25 February 2006 (UTC)
- "Length appears to contract because of the time dilation." Heh. You might as well say that time appears to dilate because of length contraction. =P Only proper length and proper time are real quantities you can depend on. —Keenan Pepper 04:09, 25 February 2006 (UTC)
- Actually, it's a little misleading to say even that lengths "appear" to contract. You can hypothetically measure the length contraction of a moving object with an array of clocks, or you can infer it with a formula like BluePlatypus says, but a single distant observer will not visually observe any contraction at all; rather, all you can see is a rotation. Melchoir 09:58, 25 February 2006 (UTC)
- Looking at time dilation and length contraction seperately is misleading. Look at the Lorentz transformation of a distance in spacetime. The Infidel 18:26, 26 February 2006 (UTC)
Most numerous particle
editWhat is the most numerous particle in the universe? (neutron, photon, neutrino, etc?) Bubba73 (talk), 04:45, 25 February 2006 (UTC)
- Not counting Dark Matter and Dark Energy, I am told most of the universe is hydrogen, therefore proton and electron equally. NOt counting photons, they are not conserved. However, I'm no expert. GangofOne 04:54, 25 February 2006 (UTC)
- My guess would be neutrinos (electron neutrinos, if you want to pick one kind). There are a heck of a lot of those. —Keenan Pepper 05:13, 25 February 2006 (UTC)
- I wondered about that. THere are alot near a star, like where we are, but they thin out as you go further out. Once again I disclaim exact knowledge. GangofOne 05:17, 25 February 2006 (UTC)
- Photons are conserved in a dilute universe; I think most of them date from the CMB anyway, and they outnumber protons by a factor of at least a billion. I don't know about neutrinos, though. Melchoir 10:11, 25 February 2006 (UTC)
- Very important detail: are you counting virtual particles in this count or not? —Keenan Pepper 17:32, 25 February 2006 (UTC)
- If you try to define the number of virtual particles, don't you run up against infrared divergences anyway? Melchoir 19:51, 25 February 2006 (UTC)
I think we need some rules to keep things interesting/meaningful - restrict to known, massive particles, probably? Photons are too weird to count. In that case, and if we assume some conservation laws, we note that protons = electrons = electron anti-neutrinos. (Ok, my nuclear physics is a little fuzzy, but I think that's right.) Neutrons don't seem to be included in this equation, but are probably less numerous. (A lotta hydrogen out there...) The addition of muons etc may skew things, so my vote is for protons.--Fangz 00:28, 26 February 2006 (UTC)
- I was not intending to count virtual particles. A friend guess photons, I guessed neutrinos. Bubba73 (talk), 00:35, 26 February 2006 (UTC)
- Photons are not too weird to count. There are some 10^88 of them in the observable universe. The ratio of photons to baryons is an important parameter in cosmology. Melchoir 01:05, 26 February 2006 (UTC)
- This is more like what I was looking far. What are figures for other particles? Bubba73 (talk), 01:06, 26 February 2006 (UTC)
- From memory, there are about 10^79 baryons. You might want to find a cosmology text for the real numbers; I don't know them. I have no idea about neutrinos; if electron number is conserved well enough, you'd expect the same number of electron antineutrinos as electrons (assuming not too many positrons), which in turn would be pretty close to the number of protons. But I'm really speculating at this point. Melchoir 01:21, 26 February 2006 (UTC)
- This is more like what I was looking far. What are figures for other particles? Bubba73 (talk), 01:06, 26 February 2006 (UTC)
- I seem to recall that 10^79 figure somewhere. So photons are probably the most numerous. Bubba73 (talk), 01:25, 26 February 2006 (UTC)
"cutting the pic"?
editIf you look under this heading, Packets/Bytes interconversion (juz scroll up) there is a screenshot. I'm wondering how do you do "cut & paste" it? I'm not asking how to paste the screenshot on this website. thks
- Under Windows, press the "print screen" button on your keyboard (in the top-right area, near the "home" and "end" keys), which will copy the current contents of the screen to the clipboard. Go into Microsoft Paint, and press Ctrl-V to paste it in. Then save the screenshot as whatever you want (*.png is good for screenshots). Under Linux, the process is different. I can't remember exactly but I think there's an app in KDE which takes a screenshot, named something like "KCapture" or "KScreenshot". And just in case you want to display the image on Wikipedia for a particular reason, you need to upload it. -- Daverocks (talk) 08:06, 25 February 2006 (UTC)
- Under MacOS, use ?-shift-3 (that's command-shift-3) to capture the entire screen, ?-shift-4 to capture a region you specify by dragging a rectangle, and ?-shift-4-capslock or ?-shift-4-spacebar to capture a window. Or, under MacOS X, you can also run the "Grab" utility, which is also available in the "Services" submenu. —Steve Summit (talk) 16:33, 25 February 2006 (UTC)
I think the question isn't how to take a screenshot. If you want to use a picture you find on a web page somewhere else, right click on the picture and choose a menu option that says something like "Save Image As..." Then, your word processor or whatever you want to insert the image into will have a menu option somewhere to insert an image from a file. rspeer / ???ds? 15:31, 25 February 2006 (UTC)
Carbon dioxide poisoning
editSuppose because of this cold winter, I insulate my bedroom (of typical size) so much that it is perfectly airtight. How long can I stay inside the room, doing normal activity or even sleeping etc., before I get carbon dioxide poisoning or other health problem? -Browni 14:02, 25 February 2006 (UTC)
- It depends on how many times you open your door to go to the bathroom or eat. Assuming you do that several times a day, you will have no problem maintaining high enough oxygen and low enough carbon dioxide to survive quite well. If you are really asking what would happen if someone sealed you in a room-sized bottle with some food and water but no plants or other oxygen source, you would die of oxygen depletion in a few days, without having anywhere near enough CO2 build-up to hurt you. alteripse 16:10, 25 February 2006 (UTC)
- Actually, in the sealed room, it is the CO2 that gets you first. Anyone in normal health can visit altitudes of 10,000-15,000 feet above sea level (3,000 - 4,500 m) without special precautions. According to this table, that corresponds to a reduction in air pressure of 31% to over 43%. In other words, the partial pressure of oxygen is reduced by 6.5 to 9 percentage points at these altitudes and it won't kill you. However, if 9% of the air at normal pressure was changed from O2 to CO2, that would be in the lethal range: see carbon dioxide.
- So how long would that take? Some web sites say that a resting adult produces CO2 at the rate of 200 ml/minute. That's a bit under 300 liters/day; 300 is a reasonable number with a bit of activity. Say your bedroom is 10x12x8 feet, that's about 1,000 cubic feet or 28,000 liters; you'd produce about 1% of CO2 per day. You'd have a headache within a day or less, and you'd be dead in something like 5-10 days. Well, it's a reasonable approximation, anyway.
- --Anonymous, 20:40 UTC, February 25, 2006.
Note that this won't just sneak up on you, the air will seem very stale first and you will find it impossible to stay in there with the door shut. StuRat 21:33, 25 February 2006 (UTC)
- I believe it's not a choice between too much CO2 or lack of O2. It's both, or rather the two mean the same thing (although I think that's what the anon meant to say). At one point there will still be enough O2, but the high CO2 concentration prevents your body from getting that out of the air. So if you'd somehow manage to remove the CO2 (not replace it with O2 like a plant does, but simply remove it) you'd be able to survive a lot longer. I believe there are fairly simple filters for that. And you could probably build one yourself. What material would bind CO2? DirkvdM 11:09, 26 February 2006 (UTC)
- You need a scrubber, sir, that contains soda lime. --Heron 13:19, 26 February 2006 (UTC)
Questions about transparencies, film negatives etc for printing/copiers/scrapboooking
editThe information I am looking for relates to the use in craft and scrapbooking projects:
What is the generic/common name for transparencies? I believe they are made from polyester or polyethylene terephthalate but that's not what people commonly recognize or say...
I have heard that matte side of transparencies for ink jet printers are generally made in an acid bath so they are not acid free (important for archival use). So unless Ink Jet Transparencies specify "ACID FREE", they are not. Is this true and are the ones made for copier acid free even if they don't say?
What is the composition of film negatives --not the film coating but the plastic sheet? Does it go by a common/recognizable name? Is it acid free?
Mylar is a trademarked name but is that the common copier stuff? Can I refer to the copier sheets as Mylar like people say Kleenex for tissues or is it entirely different? (If it's different, what is Mylar?)
Is acetate acid free and is that the copier stuff? (Or what is acetate?)
Are there other places this acid free material is used? (Like soda bottles or the clear plastic covers of fruit take out containers?
- I actually call transparencies by that name, but I have heard others call them "flimsies". Incidentally, always store them with blank paper between them to prevent them from sticking together. Ink transfer from transparencies to whatever they touch seems to get worse with time and pressure. I therefore recommend storing a paper copy so you can recreate the transparencies if the old ones are damaged. StuRat 21:28, 25 February 2006 (UTC)
- Celluloid used to be what was primarily used. Now, many plastics are used. In film, the sticky problem is solved by encasing the image between two clear layers of celluloid. --Kainaw (talk) 23:31, 25 February 2006 (UTC)
HTML Index
editDear all,
I need to create an ePortfolio that stores all of my documents. How can I make a searchable index? (i mean a search bar, when i type in "hello", it goes to a page containing the document "hello")
Also, is it possible to integrate flash into Microsoft Powerepoint? I mean i got hold of a nice flash script and wanna put it in microsoft powerpoint (when i click "slideshow", the flash runs automatically on its own and when it ends it would go to slide 1). Is it possible?
Thanks for all the time!
- You can add google seach to your website [7]. As for flash in a powerpoint presentation, Macromedia has info on that [8]. --Kainaw (talk) 00:56, 26 February 2006 (UTC)
Yahoo Messenger problems
editI had installed Yahoo Messenger version 7, minor version 437 (the latest from their website) and am facing a lot of problems since the last few days. Is there is a list of known bugs somewhere ? Is there is a discussion forum where people can post and discuss the bugs with this version ? Is anyone else using this version and facing problems ? Jay 15:29, 25 February 2006 (UTC)
What font size?
editIam using opera browser. I mostly use the desktop for reading. What font size should I use in pixels to read comfortably? I use 15 inch LCD in 1024x768 resolution.
- Your own eyes are probably the best judge of that. You should experiment with different sizes until you find one that works best. --Optichan 19:57, 25 February 2006 (UTC)
- And don't forget font type also makes a difference. Serif vs. sans-serif? Some argue, for instance, that a sans-serif font is better for web browsing (although I don't think the text "flows" nicely in sans-serif). As said above your eyes are the best judge. -- Rune Welsh | ταλκ 22:17, 25 February 2006 (UTC)
I would say that it is best for Arial, size 14 or 12. It suits my eyes perfectly, but Optichan is right. The Ronin 00:33, 28 February 2006 (UTC)
Homogenised fats
editI saw a "Tonight" programme on Uk Tv on 24.2.06 about the undesirability of homogenised fats in processed foods. Can anyone tell me what other terminology to look for on food packaging as not many products include the term "homogenised ( or partially homogenised) fats". Are "emulsifiers" the same thing?
- Are you sure they weren't talking about hydrogenated fats? I've never heard of "homogenized" fats, but hydrogenated fats contain trans fat which is widely believed to be bad for you. —Keenan Pepper 17:37, 25 February 2006 (UTC)
If I remember correctly, "homogenised fat" is another (marketing?) term for a saturated fat. Thus "partially homogenised" would conform to Keenan's explanation above. Emulsifiers in this context are compounds that stabilize fats in water, and sometimes vegetable oils are used for this purpose, but that depends on the specifics of the product you're looking at. -- Rune Welsh | ταλκ 20:10, 25 February 2006 (UTC)
- "Partially hydrogenated soybean oil" is one little nasty to watch out for. StuRat 21:20, 25 February 2006 (UTC)
Any kind of partially hydrogenated oil is a nasty one. (The word saturated means essentially the same as hydrogenated, unless you want to nit pik. It means the carbons are "saturated" with chemical bonds to hydrogens) When I lived in America I could always tell the difference when looking at the junk food packages between snacks that contained "plain" vegetable oils, verses those that had hydrogenated vegetable oils, because the law requires specification on the ingredients list there, in America.
Now I live in Australia and I suspect the law allows hydrogenated vegetable oils to be listed simply as whatever kind of vegetable oil it was before hydrogenation. I never see any indication on the ingredients list here if the oil has been hydrogenated or not. If my suspicions are right, then there is sure to be huge heath consequences for the Australian public, as there is a world of difference health-wise between.
To hydrogenate, or partially hydrogenate an oil, it has hydrogen added to the carbons of the fatty acid chains of the triglycerides. The more hydrogen that is added, the firmer the resulting product is, and the higher the melting point. This is why it is almost always partially-hydrogenated for food. Partially hydrogenated fats are softer than fully hydrogenated stuff. They use very hot nickel catalyst for this process. The result is a solidification of the oil so that it is no longer liquid at room temperature.
Some are naturally more hydrogenated, such as all animal fats (think lard) and a few from vegetable sources. That is one of the reasons animal fat is worse for you than most vegetable oils, because it is naturally more "partially-hydrogenated." If they are liquid at room temperatured then they are called oils, and that is the best way you can tell the difference. It would be interesting to know if your country requires any kind of designation on the package, but you will get a good indication if you see what it looks like at room temp. Maybe another person will tell us about labeling requiremnts in the UK ---Leah
Vertebral process
editOne of the processes of a lumbar vertebra was described to me as looking like a "scotty dog", and I understand that a particular deformity in this process, where it is either incomplete or so thin as to likely break before birth, leads to some danger of the vertebrae moving relative to each other and endangering the spinal column. Which process is this, is there a name for the deformity, how great is the risk, and what implications might it have for the owner of the vertebra, for example in choosing safe physical activities? Thank you. Pissant 16:55, 25 February 2006 (UTC)
- You can find a bunch of useful links if you Google lumbar vertebra scotty dog.
- The 'Scotty dog' appears in an oblique radiograph of the lumbar vertebrae. In an oblique view (shown here) the 'legs' of the Scotty dog are inferior articular processes; the 'ears' are one of the superior articular processes; the 'neck' is the pars interarticularis. If the pars is fractured, the Scotty dog will appear to be wearing a collar. The condition is called lumbar spondylolysis—a topic on which someone here ought to write an article.
- There's are excellent sketches of a vertebra in various orientations here, there is also a description of the common radiographic projections.
- This site has a number of useful diagrams and describes various treatment options. TenOfAllTrades(talk) 19:04, 25 February 2006 (UTC)
Thank you for your very helpful and informative response. I have started a stub article at spondylolysis, with various redirects. Another editor suggested merging the article with spondylosis, but I believe this to be an error. Opinions? Thank you again. Pissant 21:13, 25 February 2006 (UTC)
- That's a good call. Spondylosis is a type of osteoarthritis of the spine, whereas spondylolysis is a vertebral fracture. The similarity of the names can certainly cause confusion, but they're quite distinct problems. I'll remove the merge tags. TenOfAllTrades(talk) 21:48, 25 February 2006 (UTC)
Types of servers
editIs a proxy server a type of file server? I sort of have an idea that it is but I'm just not sure. Please respond ASAP because it's a course work that i'm currently working(on networking) on and I need to be precise. Thank you!
- No, a file server stores files and sends them to someone who asks. A proxy server is a network protocol relay. Now there are cacheing proxies, which do store some of the content they forward for a period of time, but this is a performance optimisation, and they're still logically quite distinct from a file server. -- Finlay McWalter | Talk 17:50, 25 February 2006 (UTC)
Organic Compounds
editAre plastics part of organic compounds? Shahid Hamid.
- Yes, the vast majority of them. But silicone for example, is not organic. --BluePlatypus 20:04, 25 February 2006 (UTC)
- To add that here organic is like in Organic chemistry. That does not necessarily imply that the atoms of that substance have ever been part of a living beeing. The Infidel 21:30, 25 February 2006 (UTC)
- Yes, because [the majority of] plastics come from oil, which itself is a hydrocarbon: a compound containing only carbon and hydrogen. Therefore, because it contains carbon, it's organic. KILO-LIMA 22:58, 25 February 2006 (UTC)
- Is carbon monoxide organic? Tzarius 00:00, 26 February 2006 (UTC)
- Organic compound says no. Melchoir 00:24, 26 February 2006 (UTC)
- Ditto the Cyanide group, though it's considered inorganic mostly by convention. GeeJo (t) (c) • 09:21, 26 February 2006 (UTC)
- Organic compound says no. Melchoir 00:24, 26 February 2006 (UTC)
- From one infidel to another, plastics are made from oil and oil is a a residue of rotting plants, so that would make them organic in the other sense as well. DirkvdM 11:15, 26 February 2006 (UTC)
- "Organic" in chemistry isn't the same as the general use of the term. Specifically, it doesn't matter whether something comes from a living organism or is synthesized in a lab. For example, iron extracted from hemoglobin is no more organic than iron extracted from mines. StuRat 07:35, 27 February 2006 (UTC)
February 26
editPlant identification
editCan someone identify this plant ? Thanks. -- Ze miguel 00:20, 26 February 2006 (UTC)
- Hmm... pretty tough being B&W, and with all the silhouetting, but I'm going to go out on a limb and guess that it's an "Areca Palm" (Chrysalidocarpus lutescens).[9] — TheKMantalk 00:35, 26 February 2006 (UTC)
- I think it looks like a spider plant, even although tha is kinda big. KILO-LIMA 12:43, 26 February 2006 (UTC)
- I'm fairly certain that it isn't a spider plant, since those have long, hanging leaves in clumps of rosettes, while the plant pictured has feathered, upright leaves. It does appear to be a palm of some sort. Another possibility could be the Kentia palm (Howea forsteriana).[10] — TheKMantalk 19:38, 26 February 2006 (UTC)
Microscope question
editWhat structures can be more easily seen in stained/dyed cells? If onion cells are plants, why can't chloroplasts be seen?
- Sounds kinda like a homework question...so I'll just be giving a few hints: Organelle size could be a factor; think of the part of the onion the observed cells come from. — TheKMantalk 01:12, 26 February 2006 (UTC)
In video games, there's the matter of passengers in a 2-door car with back seats...
editIn various driving games where passengers can enter your car, if there are four doors and four seats, they can use all the four seats just fine (even though in the real-world, the back seat could oftentimes sit three instead of just two.)
However, in those same driving games, if I drive a coupe or otherwise a two-door vehicle with back seats, why don't the AI players ever pull the front seat forward so they can get into the back? In a few games, even the player character can get into the back seat, but also only when there are four doors.
The games I talk about so far are Grand Theft Auto: San Andreas and Mafia: City of Lost Heaven.
So,
1. Why can't the game devs make back seats accessible in two-door vehicles?
2. Are there any games in which two-door vehicles have accessible back seats?
--Shultz III 01:29, 26 February 2006 (UTC)
- 1: The devs were too lazy to create chair-seat-bending-forward animations and extra character animations (after all, if they wanted characters to sit in the back seat, it was simpler to just bring up a 4-door car.)
- 2: I imagine that there are a few non-lazy game developers out there somewhere, but I can't name any games. — TheKMantalk 01:36, 26 February 2006 (UTC)
- The rear seats of those vehicles have been removed and replaced with amplifiers and subwoofers. Sharkford 17:22, 27 February 2006 (UTC)
- Certainly unintuitive if the back seats are present and empty; game devs often sacrifice realism for fun and/or resource constraints, but real objects in a game should make intuitive sense. Seahen 14:05, 5 March 2006 (UTC)
How to change the speed of a motor
editI am trying to adapt a fan motor for another purpose, but it turns much to fast. I want it to turn a set of pullies. Is there a way to monkey around with the electricity supply to make it turn slower? I also have the option of modifying a toy car, the wheels of which turn more slowly. But the problem with the car is that it is battery powered. Is there a way to connect it to house current? Now I know that you're probably just itching to toss a few links at me, but before you do that please just check that they won't bury me in maths and physics. "How to" is what I really need. ---Thanks, Leah
- General rule: The more electricity you put into an electric motor, the faster it goes. The less you put in, the slower it goes. For the battery powered motor, you'll have to get an AC to DC adapter (Radio Shack has a wide variety). See how many volts/amps the battery is (it is printed on the battery) and get an adapter that is close. For the fan motor, you'll need to put something inline to limit the voltage. A dimmer switch for a regular light will do. Try not to electrocute yourself. Feel free to trip a circuit or two - that's how you learn. --Kainaw (talk) 02:20, 26 February 2006 (UTC)
- A lower-tech, but possibly more difficult solution might be to install two different sized gears between the motor and the pulleys. ×Meegs 03:32, 26 February 2006 (UTC)
- Gearing would be more efficient, as fan motors are not particularly powerful. But if you're using pulleys anyway, just run a belt from the fan spindle round a larger diameter shaft in order to step down the speed. --Shantavira 10:10, 26 February 2006 (UTC)
- Thanks, y'all. I went with the fan motor and the dimmer switch. didn't even trip a breaker! However, as Shantavira thought, the fan motor is not very powerful. it either runs too fast or stops completely. Its going to take a lot of tinkering to get it to run a constant, slow speed. I'll experiment more with pulley size and so forth as you suggest.Hmmm...about gears? you might see a similar question in a few days. thanks a ton, Leah
Non-Newtonian fluids
editWhat's the difference between a dilatant fluid and a rheopectic fluid? Which one is oobleck? —Keenan Pepper 03:50, 26 February 2006 (UTC)
- Oh, now that I actually read Rheopecty it says oobleck is dilatant. So, what is an example of a rheopectic fluid? —Keenan Pepper 03:54, 26 February 2006 (UTC)
- I have to say that that not knowing much about the subject, that statement seemed very Jabberwocky to me. GeeJo (t) (c) • 09:16, 26 February 2006 (UTC)
- As an actual answer, this page gives gypsum paste and printers ink as examples of rheopectic fluids, and yoghurt and paint as examples of theopectic fluids. GeeJo (t) (c) • 10:04, 26 February 2006 (UTC)
- No, theopectic fluids are what they put in religious statues to make them appear to bleed on saints' days. --Heron 13:09, 26 February 2006 (UTC)
- Bah, I meant thixotropic. GeeJo (t) (c) • 17:17, 26 February 2006 (UTC)
- No, theopectic fluids are what they put in religious statues to make them appear to bleed on saints' days. --Heron 13:09, 26 February 2006 (UTC)
- As an actual answer, this page gives gypsum paste and printers ink as examples of rheopectic fluids, and yoghurt and paint as examples of theopectic fluids. GeeJo (t) (c) • 10:04, 26 February 2006 (UTC)
- I have to say that that not knowing much about the subject, that statement seemed very Jabberwocky to me. GeeJo (t) (c) • 09:16, 26 February 2006 (UTC)
CRT Glass for LCDs
editWe use a glass in front of CRT monitors. Can the same glass be used in front of LCD monitors? Is there any special glass especially for LCDs?
- A glass? You're talking about those "screen protectors"? Technically, you don't need those at all on LCD displays. I even have my doubts they're any use on CRTs. ? ?i?ff?? 06:12, 26 February 2006 (UTC)
- Not quite sure what the question is, but the glass for a CRT monitor has to be much stronger (and is therefore much heavier) in order to withstand atmospheric pressure. On an LCD monitor the glass or plastic face can be quite thin and light. --Shantavira 10:17, 26 February 2006 (UTC)
- Maybe the questioneer means anti-glare screens. These are especially useful for CRT's with a curved surface. LCD's use a flat screen, so any glare will come from a light source in one specific spot (right behind the user if he sits straight opposite the screen). Make sure there is no light source at that specific spot (or, rather, smaller area than with a curved screen) and you won't have any glare, so you won't need the screen. DirkvdM 11:24, 26 February 2006 (UTC)
- The glass in CRT monitors also contains lead, to protect against the X-rays. kmccoy (talk) 03:00, 3 March 2006 (UTC)
what is a skelton?
editquestion from Wikipedia:Newcomers help page
- Take a look at our article on the topic:Skeleton - cohesion★talk 05:52, 26 February 2006 (UTC)
- If you really meant Skelton then that would be the best place to look - Adrian Pingstone 09:31, 26 February 2006 (UTC)
Hypovolemic Shock
editI was giving a lecture on treating bleeding to a first aid club at my school. I was trying to figure out how much blood you can lose into each leg. Most sources seem to agree that there are about 6 liters of blood in the average adult. I think you can lose 1 or 2 liters into each leg, and since 1 liter alone is considered significant blood loss, the amount of blood that can be lost into each leg is an important consideration with respect to hypovolemia (hence leg elevation is taught as an easy intervention in treating shock).
I've already taught the lecture, but I'm still frustrated that I couldn't find this info, even from an EMT textbook (maybe I needed BTLS). If anyone has a figure for me, I'd apreciate it. And please, update my talk page if you reply. Thanks. Shaggorama 05:55, 26 February 2006 (UTC)
- Our article on hypovolemia says that blood loss of 10–20% may be tolerated without clinical symptoms. This site roughly agrees, putting the threashold at 15% for Type I hemorraging. Another complication is that the symptoms will depend on the health of the individual: shock will be worse in an individual who has not eaten recently, for example. Physchim62 (talk) 12:36, 26 February 2006 (UTC)
The only way you lose blood into a leg in rapidly dangerous quantities is by severing of the femoral artery. Bleeding from severing the femoral vein or severe fracture of the femur is slower. In first aid for bleeding, the highest priority is to stop the blood loss by reducing the flow into the severed vessel (tourniquet) or by direct pressure on the bleeding site. The position of the legs does not have a major effect on bleeding. The reason for the practice of elevating the legs is to reduce pooling of blood there if blood pressure and venous return from the legs are becoming ineffective-- this is mainly worth doing in shock that does not involve injury to the femoral artery, vein, or femur. If a person is bleeding from an injury to the femoral artery, he needs an effective tourniquet (or compression) quickly, not elevation of the legs. If all you do is elevate the legs he will die almost as quickly as if you have done nothing. On the other hand, if the hypovolemic shock is not due to an injury to the legs, elevation may be of temporary first aid value (though not much). Elevation of the legs may buy a little time, but is mainly one of those measures that gives people something to do while waiting for more effective help (like smelling salts); by itself it isn't likely to save a life. alteripse 17:53, 26 February 2006 (UTC)
Hey thanks for responding...just came back to point out that A) neither of these replies actually answered my question, although B) alteripse came closest by acknowledging it. To reiterate: I don't care about what defines a severe blood loss. I don't care how blood is lost in the leg. I just want to know how much blood the legs can hold. Obviously, in referring to leg elevation as a treatment for shock I'm assuming pooling from internal bleeding. I WANT TO KNOW HOW MUCH BLOOD CAN POOL IN AN AVERAGE ADULTS LEG. Not that complicated, but apparently the question meritted rephrasing.
PS: a tourniquet should be the last consideration in treating a hemorrhage of any kind, and therefore shold not be raised in any meniton of "first priority" in treatments. Furthermore, elevating the legs is "worth doing" on any patient where any type of hypovolemic shock is even a suspected complication. Moreover, I never said that elevating the legs should be the only intervention (are you implying that a tourniquet should be?), but considering how effective it can be and what an easy intervention it is, it certainly deserves more credit than I feel you are giving it. From your user page, you seem to have a strong background in medicine; but I wonder what your experience in emergency medicine has been. Shaggorama 10:39, 1 March 2006 (UTC)
What surface is (theoretically) survivable to land on from a high fall?
editSay you fall off of an airplane and your parachute (+ reserve) somehow doesn't work (or you simply don't have one when and wherever you fall.)
A fall over water will still kill you because of its surface tension. Therefore, what surface can theoretically save you after a long fall? For example, would it be an ocean or lake of whipped cream? How about Jello?
In case anyone thinks about it- no, it wouldn't be a mattress factory because Serta and other bedding manufacturers hadn't bothered to line their roofs with mattress foam. --Shultz III 11:41, 26 February 2006 (UTC)
- According to our terminal velocity article, a human can slow their speed in free-fall from 200 to 120 Mph (320 to 195 Km/h) by correctly positioning their limbs. The key to avoiding damage is to minimize your deceleration, the amount of time it takes you to slow from 120 Mph to 0 once you contact the ground. I don't know the properties of whipped cream, but if it were soft enough to slow you down gradually over a significant portion of a second, you'd probably be ok. ×Meegs 11:54, 26 February 2006 (UTC)
- A fall over water is not necessarily fatal in itself: see, for example, La Quebrada Cliff Divers. Physchim62 (talk) 12:25, 26 February 2006 (UTC)
- You might want to read Unplanned Freefall?. It mentions a few successful unplanned descents, and is amusing, too. Deep snow seems to be one of the best surfaces to land on. --Heron 13:03, 26 February 2006 (UTC)
There have been several instances of people parachuting, having their chute fail to deploy, and surviving impact. The three cases that I remember were a person falling into a marsh, into snow, and the third fell onto the roof of a car. Raul654 13:07, 26 February 2006 (UTC)
- Many of those cases featured a partially deployed parachute, so some slowing still occurred. StuRat 07:19, 27 February 2006 (UTC)
- Also, in the first two cases (the marsh and snow) the people were uninjured; they got up and walked away. In the third case, the guy broke both legs but was otherwise uninjured. They key to survival is to distribute the impact throughout your body - e.g, fall flat on your back. Raul654 14:34, 26 February 2006 (UTC)
- Also suitable trees, as mentioned on the page cited above. I've read elsewhere that Nick Alkemade came through his fall without so much as a broken bone, and when he was taken prisoner the Germans didn't believe his story until he pointed out that the clips where his parachute would have been attached had obviously not been used. --Anonymous, 20:00 UTC, February 26, 2006.
- Incidental question: Have those life jackets we are all taught to put over our heads ever saved any lives, or are they just there to make us feel a bit safer? --Shantavira 13:12, 26 February 2006 (UTC)
- Well, there have certainly been crashes of airliners into water where many people survived. Here are details of three from http://www.planecrashinfo.com: one from 1968, one from 1970, and one from 1996. I don't know specifically whether any passengers survived by using lifejackets, but it seems likely enough. --Anonymous, 20:00 UTC, February 26, 2006.
Are you the kind of person who sits on an airplane ride and ponders uselessly about what you would do if you fell out? I know I am, and its a lousy way to spend 2 hours. Anyhow, I thought i would raise a few points. One, its not the surface tension of the water that would make it painful (surface tension is apparently often confused with substance viscousity). The reason a water landing is not as desirable as you think is that the decelerative force of the water once you hit it is still substantial enough to break your bones and/or rip the flesh from them, caused by water's friction and its density vs viscousity. Best case terminal velocity, as someone mentioned, is still well over 100 mph and whatever you land on will decide how far of a distance that is spread out over (mathematically, the distance related to the deceleration is measured in G force). The key is to find something that will greatly spread the deceleration out, resulting in the lowest max G force on your body. A single mattress will only be marginally better than hitting bare ground, you only gain a few inches of deceleration time. Falling into whipped cream or jello may slow you down gradually, but by the time you had enough of it (i would hope for at least 4 feet worth) falling into it would result in you being stuck at the bottom, at which point you have a new problem, namely there wont be much to breathe in there so you will need a quick exit plan.
- It's been mentioned already, but trees are supposed to be the best thing to fall in. I believe most people who survived something like this fell into a tree. Also, irrespective of the material, a slope would be helpful. In both cases you don't get one big blow but several smaller ones.
- Another factor is how one falls. With any fall or similar crash (car crash for example), being relaxed makes a big difference. (Alcohol might help there, but you won't have enough time to let that take effect :) ). Broken limbs are partly a result of having them tensed up. About falling on your back - that seems logical from the reasoning that one should spread the force exerted on the body. But the spinal cord is also a rather vital organ. If you land on your feet (literally) you might smash your legs, but still survive. Unless you fall on a car, I suppose, because there, with the weak material but a big air pocket below it, you need the spreading of the force more. If you landed on your feet, you'd just crash through the roof and hardly get slowed down. Oh, and speaking of roofs, those inflated sports halls would constitute a wonderful pillow. And what about the millennium dome? Which Bond film was that again? DirkvdM 11:25, 27 February 2006 (UTC)
- The World Is Not Enough. --Anon, 07:35 UTC, February 28, 2006.
Vacuum
editHi all, Can someone help me understand the "Vacuum" concept because i couldn't understand if i have a bottle for example and suck out all the air in it , how can it simply contain nothing and y doesn't it crash or something? Thanks Yasmeen
- Yasmeen - normally, when you have that bottle (filled with air), there are air molecules bouncing around inside of it and outside of it. Every time an air molecule bounces off the side of the bottle, it pushes it a little bit. So the air molocules inside the bottle bounce off the inside and push out, and the air molecules on the outside bounce off the outside and push in. As a whole, the air tends to exert a pressure across the side of the bottle - we call this air pressure. In most cases, you have the same density of air inside the bottle and out, so the air pressure is equal.
- If you were to pump out all of the air from the bottle, there would be no molecules on the inside pushing it out. However, the air molecules on the outside would still be pushing in. If the material wasn't strong enough, the bottle would implode. (For the exact same reason a submarine implodes if it dives too deep) Raul654 11:52, 26 February 2006 (UTC)
- That's all true. An evacuated bottle is subject to the force of air pressure outside, which is not infinite: at sea level it is about one kilogram force per square centimetre or 15 pounds force per square inch. As long as the bottle can withstand this pressure, it will survive. Bottles are particularly strong because of their round shape, which resists compression like a Roman arch. If you put the same pressure on a flat-sided glass box made of bottle glass or window glass, it would be crushed.
- You have to remember that a vacuum is not a magic substance that "sucks" with infinite force. It is just a lack of pressure in one place compared with a higher pressure somewhere else. --Heron 12:49, 26 February 2006 (UTC)
- Just to add to the above, atmospheric pressure is really not very strong. I would guess that squeezing the bottle in one hand has about the same effect as emptying it of air. --Shantavira 13:01, 26 February 2006 (UTC)
- An good experiment to give you a feel for atmospheric pressure is to take a plastic syringe about one inch in diameter (one without a hypodermic needle), push in the plunger, seal the nozzle with your thumb, then pull the plunger out. You will need a force of about 12 pounds. That is what atmospheric pressure feels like. --Heron 13:26, 26 February 2006 (UTC)
The strength of the material itself is another factor to consider. That's the reason why normal light bulbs are often made of glass and not plastic. -- Rune Welsh | ταλκ 14:29, 26 February 2006 (UTC)
- Plastic light bulbs? The problem there would be heat resistance rather than strength. Polycarbonates are plenty strong enough. --Shantavira 16:03, 26 February 2006 (UTC)
- How about light emitting diodes? They are made of plastic. --HappyCamper 18:45, 26 February 2006 (UTC)
- They're not hollow. ? ?i?ff?? 19:01, 26 February 2006 (UTC)
- It's got nothing to do with them being hollow. They don't produce as much heat as a candescent glass light bulb. Here's a fun experiment that you wont forget in a long time. Switch on a glass light bulb for 10 minutes and then go and touch it. Kinda toasty, huh? That's why they don't make plastic light bulbs. (btw, don't touch hot light bulbs) --Username132 20:16, 3 March 2006 (UTC)
Another good experiment: take an empty soda can and heat it over a flame. This will expel a good deal of air fromt he can, while the remaining air continues to exert atmospheric pressure on the can due to the high temperature. Once the can has gotten good and hot, stick it open-end down into cold water. Because the temperature of the air kept the pressure of the interior of the can equal to atmospheric, rapidly changing this temperature while isolating the interior of the can rapidly reduces the pressure in the can. This drop in pressure is observed as an imlosion. In short, heat the can, dunk it head down into cold water, and it will implode in a big crunch. Shaggorama 11:26, 1 March 2006 (UTC)
Bird Anatomy
editI want to know the name of the thing (gland?) that exists in a hollow of a chicken's hip-bone (pelvic bone) right next to the spine (backbone). They (two per chicken) taste delicious, but I don't know what to call them (good eats?). WAS 4.250 13:46, 26 February 2006 (UTC)
- I would guess they're its kidneys. --Shantavira 16:40, 26 February 2006 (UTC)
- I tasted a cooked mammal kidney once and it had a slight odor/taste of urine. Never tasted one again. The organ/gland pair in chickens I am refering to tastes nothing like that and looks nothing like a mammal kidney. They look more like a pair of pancreases, an inch long and a quarter inch in width, space filling in shape, nestled tight in the pelvic bone hollow. Internally they are such that I have wondered if they are lung tissue. I suspect they produce digestive juices. Every fourth or fifth whole chicken I buy has a pair of smaller than pea sized kidney shaped organs with smooth surfaces like mammal kidneys dangling near the spine more in the abdomen than the hips- I bet those are the chicken kidneys. WAS 4.250 19:02, 26 February 2006 (UTC)
- I hate to gross you out, but if they are in the pelvis, they may very well be reproductive organs, analogous to the mammalian ovaries or testes. StuRat 07:09, 27 February 2006 (UTC)
- Yes, I've considered that. That is a good guess also it seems to me. It doesn't gross me out. They taste good. Once, years ago, I was eating a vegetarian sandwhich and bit my check very badly; the blood flowed. After a minute of bad pain, and not spitting it out as I was in public, I noticed my mouthful of vegy food was far far far better tasting now that it was mixed with my blood. Now knowing that on a desert island with only plants to eat I would add flavor even using my own blood if I had to, I know I was born to not be a vegetarian. I was born to be a meat eater as surely as I was born to be an oxygen breather. WAS 4.250 01:02, 28 February 2006 (UTC)
- I'm pretty sure I've observed the organ you are talking about, and I'm fairly convinced it's a lung. If I'm right, despite how nice it tastes, you may want to reconsider eating it before investigating the conditions chickens are raised in (unless you don't mind eating aspirated fecal matter). Shaggorama 11:28, 1 March 2006 (UTC)
Lung tissue is indeed a good guess (avian lungs are very different from mammal lung). But microscopic insect parts and droppings are everywhere. We breathe in mite shit. Do you eat sausage that uses animal casing (pig intestine)? Being squeemish is just silly. Why should I care if microscopic shit is in it? I do cook it first! And if there were enough shit in it to matter, I could taste it. WAS 4.250 19:09, 1 March 2006 (UTC)
What is difference between De-interlacing and Inverse telecine?
editI think they are similar thing, but they do have some subtle difference, would somebody kindly tell me what is/are that/those?203.186.238.180 12:35, 26 February 2006 (UTC)
- See deinterlacing and telecine. --Heron 12:53, 26 February 2006 (UTC)
- Basically, inverse telecine is much better. With inverse telecine, you get back the perfect individual frames of the original, whereas with deinterlacing you get blurred averages of the interlaced fields. —Keenan Pepper 16:48, 26 February 2006 (UTC)
It is against the US copyright law if I provide a Microsoft office/windows CDISO without giving out any CDKEY/Serial number?
editAs the headline said... (unsigned)
It depends on things you haven't told us. Provide more details, or read fair use. WAS 4.250 13:51, 26 February 2006 (UTC)
- If you're copying your CD for a friend, it's almost certainly a violation. Superm401 - Talk 22:17, 26 February 2006 (UTC)
IANAL, but it will depend on a number of things. Giving the number, in the abstract, is not against copyright law, since the number itself is not copyrighted, but there is a possibility that the act of giving the number is part of a crime if it is a part of a copyright infringement. If your friend has a legal copy of the software, and you give a number as part of some kind of technical support, it is liekly legal, if you are giving the number in order to allow them to run software that they don't hold a license for, it is likely not.
- IANAL either, but in the US, just giving the number could violate the DMCA anti-circumvention provision. That basically says (the law is vague) that you can't deliberately circumvent a copy-protection system (even if this would otherwise be fair use). Superm401 - Talk 03:26, 28 February 2006 (UTC)
Accounting by WPP and google
editTwo questions here-
1) How do Advertising agencies like WPP and O&M do accounting? If an ad costs $100 in a newspaper, and $15 goes to WPP as commission, then will $100 add to the revenues of WPP or will only $15 add to the revenues of WPP?
2) I also would be interested in how Google does accounting. If Google acts as an advertising agency by way of placing ads in other websites through their adsense program, then- Please assume I am a blog site owner and an ad is placed in my site, and the advertiser pays $1 for 100 inpressions. I get 50 cents. Now, will Google's revenues increase by $1 or will it increase by 50 cents?
Thank you
- These are related questions, both of which concern who gets the money. In both cases, a company (the one the ad is for) contacts an ad agency (WPP Group or Google), who places an ad with a media company (a newspaper or your blog). The media company charges for access ($85 for the newspaper ad, assuming $100 total cost and $15 commission; 50 cents for your blog), and the ad agency collects a fee ($15 or 50 cents). The question is, does the company pay these two costs seperately, or with one cheque?
- If they cut one cheque, then, using the WPP example, WPP gets an income of $100, and immediately spends $85 on buying newspaper ads, which they list as an expense. If the company cuts two cheques, the newspaper gets $85 directly, and WPP gets $15 which is income, and then has no cost of sales expense (except labour).
- Look at one ad agency's financial records [11]; click 2004 financial statements, go to the income statement, page 134. (I'm rounding the numbers here:) They bill $35.9, with cost of sales at $28.0 and revenue of $7.9. It seems that cost of sales eats up the majority of their revenue. So most of their billing is cost of sales, which I would expect if they had to pay for the newspaper ads and whatever. This makes sense - if I'm running Pepsi, I want to write one cheque to WPP and have them take out ads in the hundreds of media companies for me. I don't want to be bothered buying space in 5000 newspapers individually. So it seems that this is the first case; WPP gets $100 income, and spends $85 on the newspaper ad, leaving $15 in net revenue.
- With Google, it seems pretty apparent that they handle the billing as part of the AdSense program; you don't put a Google ad on your website and then start sending out bills for 0.5 cents to whoever advertises. (You don't even know who's advertising.) So Google would get revenue of $1, and then have an expense of 50 cents, which is their cost of media exposure.
- So, in both cases, the same accounting. They get the full cost of the ad campaign as income, but they also spend a big part of their income on buying media exposure. Which is the same as any company, really. If you buy a $1500 computer from a computer store, they get $1500 income, but they had to spend $1300 or whatver to buy that computer from the manufacturer. ByeByeBaby 21:49, 26 February 2006 (UTC)
Your answer was in-depth & useful. Thankyou-Poster of the question
Sleeping with head northwards
editIs there any scientific reason behind the popular belief that it is not good to sleep with head towards north?
- This is a total guess, but it could be related to the old christian burial custom of always placing a body with the head to the west and feet to the east. Raul654 16:27, 26 February 2006 (UTC)
- How is this a scientific reason? ? ?i?ff?? 17:01, 26 February 2006 (UTC)
- It's a scientific explanation, just not a scientific basis. Markyour words 21:42, 26 February 2006 (UTC)
- Well I thought it was supposed to be good for you. More research needed obviously, but I would have thought it was nonsense. --Shantavira 16:44, 26 February 2006 (UTC)
- My guess is: there is none. ? ?i?ff?? 17:01, 26 February 2006 (UTC)
- I remember reading years ago about a belief that aligning the body with the directionality of the magnetic field of the Earth was supposedly beneficial. JackofOz 20:00, 26 February 2006 (UTC)
- Keyword: supposedly. If that was true, we could always walk facing north then. Wouldn't that be a thing? ? ?i?ff?? 22:26, 26 February 2006 (UTC)
- I thought I'd seen something about this. I searched our journal catalog and couldn't find anything. The conclusion of the study is that people either find it easier to fall asleep when switching their direction 180 degrees, or they find it more difficult. The rarely find it the same. While it did have a true result (sleeping in the opposite direction does affect how easily people fall asleep), I remember it because it was worded in a funny way: either they find it easier or harder. It sounded to me like saying either it will rain tomorrow or it won't. --Kainaw (talk) 01:48, 28 February 2006 (UTC)
- It might be related to the Chinese custom of thinking of the South as an auspicious direction. For instance, a particular Chinese emperor had a chair that he used while traveling that was designed to always face South. grendel|khan 21:58, 3 March 2006 (UTC)
Hypnotizing animals
editIt seems that chickens and trout can be hypnotized, though not snakes (at least according to Wikipedia). Can this really be hypnotism? Or is something else going on? What about other animals? --Shantavira 16:53, 26 February 2006 (UTC)
- Seeing we don't have a particularly good understanding of how hypnotism in humans actually works, it's rather hard to say. --Robert Merkel 09:21, 27 February 2006 (UTC)
The Phlogiston Theory!
editI do not understand this part of the Phlogiston Theory and i would be very grateful if you could help me:
"Charcoal leaves hardly any ash when it burns because it is almost pure phlogiston."
What reasons prove this theory is wrong and what proves it right?
Thank You Very Much!!
- See Phlogiston theory. (Smells like homework). - Cybergoth 17:52, 26 February 2006 (UTC)
- Homework questions of phlogiston? Good grief! They'll be asking homework questions on intelligent design next. (Oops!) --Shantavira 18:43, 26 February 2006 (UTC)
- Since phlogiston doesn't exist, there are no reasons which prove the theory right. Markyour words 21:44, 26 February 2006 (UTC)
- I disagree, many incorrect theories still have some evidence to support them, just less than the evidence against them. StuRat 07:04, 27 February 2006 (UTC)
- Evidence in support of a theory is not proof of a theory. Markyour words 21:24, 27 February 2006 (UTC)
- He may have meant, "For what reasons did scientists used to think it was right?" Black Carrot 01:34, 28 February 2006 (UTC)
- One of the findings cited to disprove the theory was that burning of metals actually increased their mass (oxidation = rusting), and therefore could not be indicative of any type of loss, as phlogiston theory required. Shaggorama 11:32, 1 March 2006 (UTC)
Wasn't Phlogiston what they called Nitrogen at the time? I remember writing the Daniel Rutherford article. — Ilyanep (Talk) 17:23, 4 March 2006 (UTC)
- Wait that was phlogisticated air — Ilyanep (Talk) 17:29, 4 March 2006 (UTC)
32-bit vs. 64-bit CPU's
editI'm looking at buying a new motherboard and CPU for my Linux system, and I'm utterly confused about the 32-bit vs. 64-bit thing. The Pentium D article doesn't say whether they're 64-bit or 32-bit; is that even a question that makes sense? If you buy a 64-bit processor, do you necessarily have to run a 64-bit operating system on it, or do you simply have the *option* of switching? Will current versions of Linux (i.e. Gentoo) work on a Pentium D without major rejiggering? -- Creidieki 18:24, 26 February 2006 (UTC)
- A complete answer would require several paragraphs. Take a look at the intel 64 bit tech in the EM64T article, and the AMD version in the AMD64 article. After that, maybe a look at the windows XP x64 article would sum things up. --24.210.26.146 19:37, 26 February 2006 (UTC)
- I looked at those articles, and I still don't understand how 64-bit operating systems are related to 64-bit processors. The 64-bit article also doesn't help. -- Creidieki 20:58, 26 February 2006 (UTC)
- If you buy a 64-bit system, you can still run a 32-bit OS. A 64-bit OS requires a 64-bit processor, but can generally run 32-bit applications alongside 64-bit applications. Device drivers on the other hand can be a problem, because a 64-bit OS requires 64-bit device drivers, and some peripherals may not necessarily have any available. Then your only choice may be to run a 32-bit OS. 84.239.128.9 21:21, 26 February 2006 (UTC)
- Hopefully i can give a consise answer thats still useable. The 64 bit processors classed EM64T and AMD64 are very similar to our current 32 bit processors, but naturally with native 64 bit memory ability and some advanced instructions to take advantage of it. This similarity makes them 'hybrid' processors in that if you dont want the full 64 bits and new features, you dont have to use them. So, a 32 bit OS can still run fine. This also means that when you choose a 64 bit operating system, it is still very possible to run 32 bit applications 'near-native' for no perceiveable performance loss. To the person not wanting any deeper of an understanding than this, here is the point: If youre buying a desktop you should get a 64 bit offering. You wont lose functionality and you wont pay much more for it, and down the road (read: windows vista) you will see a sharp benefit from having it. --24.210.26.146 21:47, 26 February 2006 (UTC)
- So the difference between the Pentium D and the Itanium is that the Pentium D is kind of "optionally" 64-bit? Will I suffer a major performance problem 3 years from now when I'm trying to run a 64-bit OS? I assume from what you're said above that the Pentium D implements IA-32 in addition to the EM64T instruction set, so it can run operating systems designed for either platform? -- Creidieki 22:02, 26 February 2006 (UTC)
- Bingo. EM64T and AMD64 are hybrid technologies that will run traditional 32 bit (x86 insruction set) operating systems just fine, along with the upcoming 64 bit (x64 instruction set). The Itanium and I-2 is based on a whole new 64 bit EPIC instruction set, and is really beyond the scope of this discussion (its 64 bit just like x64, but the instruction set is different, and that's what breaks compatibility). Honestly, if you are using the same CPU 3 years from now as you are today, you will be suffering a performance problem but it won't have anything to do with bits or instructions. A x64 dual core system presents the strongest upgrade path at this time, but in 3 years who knows what will be around.
- Re: "You wont lose functionality" -- actually you might lose the ability to use important hardware or software compared to running a 32-bit system. As noted all device drivers must be rewritten, and device drivers can turn up in unexpected placed. For example Adobe Acrobat Professional 7.0 does not fully work in 64-bit Windows XP. The bottom line is to carefully check for an explicit compatibility notice for everything you want or need to run. Nobody is saying "everything will run" but unfortunately many people go around with this message in their heads and later get hurt... Notinasnaid 04:49, 27 February 2006 (UTC)
- See, I said it would get complicated. You won't lose any functionality with the type of *cpu* you choose, whether it be 32 bit x86 or 64 bit x64. You can still run your choice of 100% 32 bit OS or 50/50 64 bit os, which is where your loss of functionality may possibly come from. As an implementer of these CPUs, I can say i have had success running all typical hardware and software on windows and linux in x64 mode.
If the present 64 bit processors are hybrids, then might future ones be pure 64 bit and will it then no longer be possible to use 32 bit OS's? Such as Win98 (yes, I still use that for various reasons). DirkvdM 12:10, 27 February 2006 (UTC)
- Unlikely—even the Itanium provides an ability to run regular 32-bit x86 code through emulation (even though in the Itanium's case, this is incredibly slow). I would assume that any consumer-class processor (Athlon, Pentium) released in the foreseeable future will include the ability to natively execute 32-bit code, though. Even after 28 years, all of today's processors are still able to run 16-bit x86 code, so I don't foresee an "64-bit only" processor being a problem. Bloodshedder 00:20, 28 February 2006 (UTC)
monkey?
editno question
- Yes, monkey. GeeJo (t) (c) • 19:42, 26 February 2006 (UTC)
- Note that gorillas, chimpanzees, humans, orangutans, and gibbons are apes, not monkeys. — Knowledge Seeker দ 19:53, 26 February 2006 (UTC)
- Monkeys have tails, but apes seldom recant anecdotes.
Slumgum 19:59, 26 February 2006 (UTC)- That's their story and they're sticking to it? --Trovatore 20:35, 26 February 2006 (UTC)
- Monkeys have tails, but apes seldom recant anecdotes.
- Note that gorillas, chimpanzees, humans, orangutans, and gibbons are apes, not monkeys. — Knowledge Seeker দ 19:53, 26 February 2006 (UTC)
- William Shatner. Melchoir 21:30, 26 February 2006 (UTC)
- Mon key? EWS23 | (Leave me a message!) 22:26, 26 February 2006 (UTC)
- This would be the perfect place for the Balloon Monkey joke from Kingdom of Loathing, cept their wiki is down. :( --AySz88^-^ 22:59, 26 February 2006 (UTC)
- Mon...key! Mon...key! Sum0 15:55, 27 February 2006 (UTC)
Monkees. User:Zoe|(talk) 03:05, 28 February 2006 (UTC)
Mon clé? Shaggorama 11:33, 1 March 2006 (UTC)
- Doesn't rhyme with donkey. For some stupid reason. Proto||type 14:15, 1 March 2006 (UTC)
Commercial Nanocarbons
editHi,
I am wondering if there are companies out there actually making parts out of nanocarbons!? If you know of any, could you kindly name them here?
Thank you.
- I'm not sure if these count as "parts" but check out the Applications and External links at Carbon nanotube. Melchoir 21:28, 26 February 2006 (UTC)
How do I change the media player in Firefox?
editI don't really like quicktime that much, I was wondering how do i change it to Windows Media Player?
- The problem here is the Firefox QuickTime plugin you most likely have. Assuming you're using Windows (since you want to use Windows Media Player), go into C:\Program Files\Mozilla Firefox\plugins (or whatever your install directory was). There should be some dlls there. Find the ones that start with "npqtplugin". You may have several; I had npqtplugin.dll, npqtplugin2.dll, npqtplugin3.dll, npqtplugin4.dll and npqtplugin5.dll. You can delete them all, as well as another file there named "QuickTimePlugin.class". Now restart Firefox, and what should happen now when you try going to a *.mp3 or *.mpg on the web is Firefox will ask you whether you want to open or save it, which is obviously where you select Windows Media Player to open. -- Daverocks (talk) 07:56, 27 February 2006 (UTC)
- Instead of deleting the plug-in file, you can also tell Firefox what to do with particular files. Go to the Tools menu, click Options, click Downloads, then click the View & Edit Actions button. Find the filetype you wish to change the action for (it may be listed several times, so change them all), select it, and click Change Action. You might want "Save them to my computer" instead of "Use this plug-in" or opening them with an external application. Also, as an alternative to both Quicktime and Windows Media Player, VLC media player offers a browser plug-in with its media player installation. Bloodshedder 00:25, 28 February 2006 (UTC)
Control+Enter IE shortcut
editIn Microsoft IE, pressing Control+Enter while in the URL box adds "http://" and ".com" to the text currently in the box. I somehow lost the ability to do this in my old computer. I just got a new computer, and after a few days, I lost the ability to do this on my new computer too. So I suspect this might be because of iTunes or iPodAgent, because these are the only two programs I remember downloading on my new computer. Has anyone else had this problem, and how do I fix it? --JianLi 01:32, 27 February 2006 (UTC)
- Try Control+Alt+Enter? I'm not sure, but the solve-all solution is to dump IE and use Firefox instead, which, by the way, has that shortcut too. -- Daverocks (talk) 07:46, 27 February 2006 (UTC)
- Go to Tools, then Options, then the Advanced tab. Turn on the Use inline AutoComplete setting in the Browsing section and the shortcut should work again. --jh51681 19:52, 28 February 2006 (UTC)
- Wow, thanks Jh51681, that worked perfectly. I had no idea it was actually an option. How did you find out about it? The weird thing is, the help description of "inline AutoComplete" doesn't even mention the control+enter shortcut.
February 27
editroms, where do i find them
editwhere would i find a good site to download roms for gameboy advanced or other emulators?
- 99.99% of console roms breach copyright laws. Stay away from them! If you are looking for good, free, downloadable games, try Home of the Underdogs, or make your way over to indie gaming and follow the links from there. --Sam Pointon 04:16, 27 February 2006 (UTC)
- Romhustler. Nuff said.
Why is China all in one time zone?
editAnyone know the answer? Is it political?
Is the border between China and Tajikistan the only political border you can cross and gain/lose 3 hours (like you just flew from New York to LA)?
-Quasipalm 04:32, 27 February 2006 (UTC)
- China does border Afganistan for a bit less than 100km, so crossing that border means a 3.5hr time change. — TheKMantalk 05:05, 27 February 2006 (UTC)
- Interesting topic. I dunno the historic reason, but I suppose that they all follow the Beijing time, hallmark of a centralised controlling government. An incidental question is why does United States have different timezones. For one thing, it's quite confusing when connecting flights. --Vsion 07:29, 27 February 2006 (UTC)
- Time zones are a strange bag of physics and politics. Ideally, each time zone should be exactly 15° wide to compensate for longitude (and even then, your watch could still be off by half an hour compared to local solar time, but this is judged acceptable). Of course, national borders and politics twist this, all the way to aberrations like China, which spans enough longitude for three-and-a-bit timezones but only has one - so, at the eastern end of China, the sun rises a full three hours earlier than at the western end, even though the clocks in both places show the same time. Vsion, if the US was only one timezone, it would be even worse - assuming it was centered somewhere in the midwest, noon would be at 10am in New York and at 3pm in Hawaii, which would be very silly. Europe is another example of politics prevailing over physics - save the British Isles and Portugal, all of Europe west of about 25°E is in one time zone, when it spans more than 30° of longitude. If done 'properly', France, Spain and the Benelux should be at GMT+0, together with the UK, Ireland and Portugal. See our article on time zone, it's rather good. — QuantumEleven | (talk) 08:59, 27 February 2006 (UTC)
The half-hour zones are even weirder. In the case of Iran it makes some sense because a 'solar zone' border runs straight through the country. But India is bang in the middle of the +5 hour zone, yet they're at +5,30 hours. And the Central Australian zone is weirder still. It looks designed to be coincide with the +9 hour zone, yet it's at 9,5 hours. DirkvdM 12:10, 27 February 2006 (UTC)
- That's a good point - could any Aussies on the Ref Desk (yes, JackofOz, that means you :)) enlighten us as to why in the world your central time zone is at UTC+9.5? It seems very random. — QuantumEleven | (talk) 13:47, 27 February 2006 (UTC)
- I've searched in vain for info about the reason it was done that way. Originally the local mean time of Adelaide was used (138E35). On 1 February 1895, the time zone was based on 135E00, and on 1 May 1899 it changed to 142E30, and it's stayed there ever since despite at least 3 attempts (1986, 1994, 2000) to change it. I can only assume it had something to do with the population of the state being concentrated in the eastern half. Or maybe it was a metaphor for South Australia's forward looking vision of the world (eg. South Australia had the first Parliament in the world to allow women to be elected as members). JackofOz 09:32, 28 February 2006 (UTC)
You may consult Time zones of China for more information in depth. In fact, zh:???? (Time zones of China) was on Chinese Wikipedia's DYK section last week. -- Toytoy 14:16, 27 February 2006 (UTC)
- Time zone changes can be confusing, and daylight savings too. Each time anyone proposes any changes in the UK, people appear out of the woodwork to complain about the loss of daylight at one end of the day or the other. Perhaps the Chinese are smart enough to realise that changing the clocks doesn't actually affect how much daylight there is, and (shock) adjust outdoor work to match. Notinasnaid 14:21, 27 February 2006 (UTC)
- I think this is a nice idea. You can travel from Singapore to Shanghai to Hong Kong to Taipei to Manila to Perth without adjusting your watch. It's lazy man's heaven! However, you still suffer from mild jet lag because you can't cheat the sun. You can't cheat Skype either. ... Well, latest Skype can display a user's local time so you know if it's proper to call. ...
- Taiwan had observed day light saving time several times in history (1945-1961, 1974-1975, 1980; start and end dates varied). People hated it. The government had to call it off. Some Chinese cities, Macau and Hong Kong had observed day light saving time too. -- Toytoy 14:49, 27 February 2006 (UTC)
- I'm also wondering why can't we all follow the Beijing-style system, everyone fixed the time at say the UTC, but start work at different time depending on local sunrise: Singapore start work at 0000hr, UK at 0800hr, california at 1600hr, etc.. I wake up at 11am everyday anyway, no problem. Wouldn't this system be better and less confusing? Daylight saving is another archaic thing, but I shouldn't complain, the worse victims are the diary cattles: for one particular day each year, the cows are forced to wake up one hour earlier than usual for milking, totally confused and irritable. Then half a year later, they have to hold the milk in their systems for one more excruciating hour; thanks to this human-invented daylight saving scheme. --Vsion 15:16, 27 February 2006 (UTC)
- It's worth noting that cows don't read clocks; their schedules only change if the farmers in question don't adjust to the time change to compensate. — Lomn Talk 18:27, 27 February 2006 (UTC)
- I'm also wondering why can't we all follow the Beijing-style system, everyone fixed the time at say the UTC, but start work at different time depending on local sunrise: Singapore start work at 0000hr, UK at 0800hr, california at 1600hr, etc.. I wake up at 11am everyday anyway, no problem. Wouldn't this system be better and less confusing? Daylight saving is another archaic thing, but I shouldn't complain, the worse victims are the diary cattles: for one particular day each year, the cows are forced to wake up one hour earlier than usual for milking, totally confused and irritable. Then half a year later, they have to hold the milk in their systems for one more excruciating hour; thanks to this human-invented daylight saving scheme. --Vsion 15:16, 27 February 2006 (UTC)
You may want to see Image:ROC-TimeZones.png. This picture shows the time zones of China from 1912 to 1945 (Taiwan was under Japanese occupation then but was also GMT+8; but Hong Kong was GMT+9 during the 1942-1945 Japanese occupation). The GMT+8 provinces (pink area) consistutes more than 80% of China's population and an even larger pie of economics (the rest of China are mostly mountains and deserts). I think it is quite reasonable for China to adopt a single time zone policy because it helps people to do business. -- Toytoy 15:28, 27 February 2006 (UTC)
- I totally agree with Vsion.It is ridiculous to change the clocks time.It is more easy to follow the UTC everywhere with particular schedule for each palce.amrahs 15:40, 27 February 2006 (UTC)
- Does anyone remember Swatch Internet Time? Thought not. —Blotwell 10:37, 1 March 2006 (UTC)
- I totally agree with Vsion.It is ridiculous to change the clocks time.It is more easy to follow the UTC everywhere with particular schedule for each palce.amrahs 15:40, 27 February 2006 (UTC)
- Personally, I think it's a good idea to adopt the time zone after your nearby economic partners. It's an even better idea that we all adopt GMT or UTC whatever you call it. I sent a package from Taipei to Washington D.C. last week, the DHL tracking system is really doing a bad job by displaying only local time. My package travelled from Taiwan (GMT+8) to California (GMT-8) to Ohio (GMT-5) to Maryland (GMT-5). It could be even more complex if it's summer in the USA. I hate daylight saving time. -- Toytoy 15:48, 27 February 2006 (UTC)
- Yeah, that's what Singapore did when Malaysia switched the whole country to UTC+8 (previously both Peninsular Malaysia and Singapore had been under UTC+7, but to accomodate East Malaysia which is in UTC+8, the whole country set its clocks an hour ahead, forcing Singapore to follow suit). Johnleemk | Talk 16:06, 27 February 2006 (UTC)
- There is also a tendency for time zones to be slanted towards longer evenings and shorter mornings. Central European Time is the equivalent of solar time in Berlin, but is used in many areas to the West: Galicia (Spain) is two and a half hours ahead of local solar time in summer. Physchim62 (talk) 04:35, 28 February 2006 (UTC)
- Yeah, that's what Singapore did when Malaysia switched the whole country to UTC+8 (previously both Peninsular Malaysia and Singapore had been under UTC+7, but to accomodate East Malaysia which is in UTC+8, the whole country set its clocks an hour ahead, forcing Singapore to follow suit). Johnleemk | Talk 16:06, 27 February 2006 (UTC)
In The United States, in the State of Indiana, the dividing line between Central Time zone and Eastern Standard Time zone runs in between the east bound and west bound traffic of Interstate 64.
Comment:
The half-hour zones are even weirder. In the case of Iran it makes some sense because a 'solar zone' border runs straight through the country. But India is bang in the middle of the +5 hour zone, yet they're at +5,30 hours. And the Central Australian zone is weirder still. It looks designed to be coincide with the +9 hour zone, yet it's at 9,5 hours. DirkvdM 12:10, 27 February 2006 (UTC)
- I believe the IST is based on the meridian (82° 30' E ) which is roughly halfway between India's two extremes, so it's a perfectly logical choice. Note that Historically, Indians were using Ujjain (75° 47' E) as the reference prime meridian (in place of Greenwich), and astrologers still use the same. deeptrivia (talk) 04:24, 2 March 2006 (UTC)
Erosion and Weathering
editWhy don't the continents disappear as they are continually worn down by weathering and erosion?
- There are several processes involved. A major one is this - the Earth's surface rocks basically float on the molten rock underneath. The surface is heavy - not heavy enough to sink, but heavy enough to sink into the molten layer to some extent (much like an iceberg floats on the surface of the ocean, with most of its contents below the surface. As the land is eroded, it floats up a little more, since it now weights a little less. Another major process is the land-building which comes from the movement of the earth's plates. In some parts of the world, one plate is passing under another, and this causes the land to rise. In other places (Iceland, for instance), volcanic activity is building the land up., Elsewhere, notably the Himalayas and Alps, plates are colliding, and buckling where the collision occurs (look at the shape of the mountains in southern Asia - they were caused by the collision of India into the Asian mainland. So yes, erosion wears the rocks down, but there are enough other activities going on which are building them up again. Grutness...wha? 06:09, 27 February 2006 (UTC)
- Another (quite minor) contribution is from dust and occasionally visible meteors from space. StuRat 06:51, 27 February 2006 (UTC)
Plate tectonics --Zeizmic 13:12, 27 February 2006 (UTC)
- They are disappearing, but erosion is a slow process, so it takes time for an entire content to disappear. - Mgm|(talk) 09:04, 28 February 2006 (UTC)
- I disagree, they are in equilibrium, with the processes listed above building them up at the same rate erosion wears them down. StuRat 05:51, 1 March 2006 (UTC)
Puberty
editAfter a teenager develops puberty, hair appears in areas of the body such as around the penis or vagina, below the armpits, and on the face. But why? I mean, what is the purpose of all this hair appearing in different parts of the body?
- No one knows. People guess. Trap smell? WAS 4.250 01:24, 28 February 2006 (UTC)
- It's compliated. Basically, it's neotony. The adult form of our species, being descended from ape-like creatures, is supposed to have hair all over its body. Hair doesn't develop until after birth, however. But as a result of hundreds of thousands of years of evolution-driven neotony, human young tend to look juvenile longer (e.g, live later without hair in areas adults have it). Raul654 06:57, 27 February 2006 (UTC)
- Humans grow hair while still in the womb. Neotony is part of why we have hair that looks small/thin/short compared to the other apes (the numbers of hairs in humans are the same as in the other apes, ours are just small/thin/short). Sexual choice (people prefering to mate with less hairly other humans) is a prime guess for why this is so. WAS 4.250 01:24, 28 February 2006 (UTC)
- Agreeing with Raul, I would just like to add that in the future, mankind may lose the need for hair, and evolution will possibly get rid of it.
The Ronin00:36, 28 February 2006 (UTC)
- Is that why I'm balding? That's comforting... --Vsion 00:41, 28 February 2006 (UTC)
- This is purely science fiction. A more fact based look into the future would note the increase in human ability to look any way they want; technological evolution replacing genetic evolution. WAS 4.250 01:24, 28 February 2006 (UTC)
- As a matter of fact, there is already a magical gizmo that allows us to change this aspect of ourselves at will. Black Carrot 01:44, 28 February 2006 (UTC)
- WAS 4.250 is in teh ball park, but not exactly right. Natural selection for humans has virtually ceased. How many people die of natural causes before hitting puberty? A vanishingly small number compared to the past.
- My uncorrected vision is (roughly) 20/800 -- basically blind. if I lived 50,000 years ago, I wouldn't have survived very long (you can't hunt if you can't see). However, with LASIK, I can live a normal, happy life. This is NOT "technological evolution" - any child I have will also get my genes for severe nearsightedness. So it's not "evolution" of any kind, as the frequency of allelles does not change (which is the definition of evolution).
- However, while natural selection has almost ceased, there is another driving force - social selection. Social selection has always been present, but as natural selection became less important, social selection became more important. Think about it this way - if someone is (for example) genetically smelly, no one is gonna want to marry him and have kids with him. Thus, he is weeded out. Social characteristics have become far more important with technology. Raul654 01:38, 28 February 2006 (UTC)
- Technological evolution is not any kind of biological evolution. Biologists don't have a copyright on the english language word "evolution". Look it up in a dictionary or even in wikipedia (pay attention to the first thing you read, it directs you to a disambig page where other articles using the word "evolution" with other meanings are described and linked to. WAS 4.250 17:58, 28 February 2006 (UTC)
Text and Image copyright confusion
editThe following was posted at Wikipedia:Clueless newbies:
What a great place. I just created an account. Did quite a bit of reading, but don't understand in simple terms if my problem is solved here.
I'm creating my first web site in XHTML and am writing a family photojournal as my learning tool. It has tons of photos that I prefer to protect with copyright on the web site. We may SOMEDAY (no time soon) use the site commercially to sell bonsais and arts & crafts products.
(1) Does not our copyright exlamation at the bottom of the site protect the images even though there are no tags? Do PhotoShop watermarks carry any weight?
(2) Is it possible to use articles verbatim about bonsai from Wikipedia and create a copyright that explains that the use of text is GNU-free-licensed, but the graphics, indeed, remain copyrighted solely to us on our web site if we follow the example page that references GNU and Wikipedia? Thanks for the help.
--InMyWords
— QuantumEleven | (talk) 09:44, 27 February 2006 (UTC)
- (1) Yes, and technically they would be protected even if you didn't specifically say so on your site (though it is always best to make it clear). Whether or not people on the internet will respect those copyrights is a different matter. Photoshop watermarks or otherwise marking the copyright on the image itself might help protect against that, if you're worried.
- (2) Read Wikipedia:Copyrights for a detailed response. — Asbestos | Talk (RFC) 21:30, 27 February 2006 (UTC)
- Yes. Our interpretation is that images can be licensed (or not) separately from GFDL text; in other words, "mere aggregation". Superm401 - Talk 03:36, 28 February 2006 (UTC)
X-Ray and Dental Problems
editAnother question from Wikipedia:Clueless newbies:
Ten year back I was working some electricity work during my working one copper wire inserted in my gum, I immediate went to the doctor and told him the entire thing doctor diagnose but did not take x-ray and told there is nothing, Time to time I went to the different doctor and told them the entire story doctor did not believe me and said if there is wire in your gum there must be some swelling and infection in the gum but there was nothing, but there is a continuously feeling that wire is in my gum
Recently one month back I went to doctor and he took two X-Ray but he did not find any thing in my gum he operate my gum and saw through high resolution Camera but result was zero, but to day as on date 27/2/2006 my tongue feeling that wire get loose and displaced Doctor say nothing is their every thing is all right it is all physiological but I feel that wire is in my gum
Pl. Answer the following
1) Can a metal wire dissolved automatically after this long period 2) If metal wire is exact behind the teeth it can be seen through X-Ray 3) In what condition Metal wire does not show image through X-Ray
Pl. suggest me the right direction and right test
— QuantumEleven | (talk) 09:49, 27 February 2006 (UTC)
- I once had a really terrible dentist, who caught a nerve while giving me an injection of novocaine prior to dental work, and to this day I can still occasionally feel swelling around the area, that almost feels like there's still a needle in my gum, however I'm quite sure I'd notice if there was actually a hypodermic needle sticking out of my face, so I'm fairly certian there's another explanation, maybe extremely trivial nerve damage, or just swelling along the tissue split by the needle, I know something similar happens after certian surgeries, where scar tissue forms along the inside of a incision, and after it heals there's a slight clump of dense tissue around where the openning used to be, resulting in one being able to "feel" someting that isn't there anymore, I know there's a better word for this--64.12.116.74 21:46, 27 February 2006 (UTC)
- And if it helps anyone figure out what the hell I'm talking about, I know it's a big problem after most heart surgeries in which the patient develops an arrhythmia as a result of irregular fiberous growth near the incision, but for some reason I just can't remember what this is called,
- but presumably you could experiance the same thing if your skin or some other tissue were pierced by a long, thin, irregular piece of metal, and then rehealed along that line, leaving a long, thin, fiberous cyst in it's place--64.12.116.74 21:54, 27 February 2006 (UTC)
- I once had a really terrible dentist, who caught a nerve while giving me an injection of novocaine prior to dental work, and to this day I can still occasionally feel swelling around the area, that almost feels like there's still a needle in my gum, however I'm quite sure I'd notice if there was actually a hypodermic needle sticking out of my face, so I'm fairly certian there's another explanation, maybe extremely trivial nerve damage, or just swelling along the tissue split by the needle, I know something similar happens after certian surgeries, where scar tissue forms along the inside of a incision, and after it heals there's a slight clump of dense tissue around where the openning used to be, resulting in one being able to "feel" someting that isn't there anymore, I know there's a better word for this--64.12.116.74 21:46, 27 February 2006 (UTC)
- 1-A copper wire could conceivably dissolve completely over 10 years; copper is not chemically inert, and would corrode and be absorbed. Whether it would be completely absorbed would depend on the gauge of the wire.
- 2-Depending on the metal composition and the thickness of the wire, it may or may not be visible behind a tooth on x-ray.
- 3-A metal wire would not be visible on x-ray if its composition and thickness caused it to have the same radio-opacity as the environment in which it is situated. It would also not be visible if it was behind or in front of a more radio-opaque object, such as a metallic filling or denture prosthesis.
- Although it is possible that you do have an embedded wire in your gum, it is unlikely that it would fully embed itself; copper is ductile, and it is reasonable to assume that it would not break off within the wound, and that at least part of it would protrude and be visible. In any event, your dentist is correct-- an embedded wire would most likely provoke a foreign body reaction, with pain, swelling, redness, or overt infection. Absence of these obvious signs would argue that your doctors are correct. Whether your perception of a wire is psychological is something else-- you could be experiencing a paresthesia from local afferent nerve injury or other neurological pathology. If your dentist is unable to determine the basis for your complaint, you might consider a consultation with your physician or a neurologist.--Mark Bornfeld DDS 15:55, 27 February 2006 (UTC)
- Forget what you think it is. Forget the past. Focus solely on what it feels like now and if it is a problem, what exactly do you want. Tell a doctor (regular or dentist - your choice) what you feel and why that's a problem without talking about the past. (If how it feels is not a problem, you don't have a problem.) Let the doctor deal with the why and so forth. Assume there is no wire inyour gums. Maybe its nerve damage. Maybe its a super-sentitivity in your brain to nerve signals from a part of your gums. I had tooth pices migrate out of my gums, after a wisdom tooth extraction. Any piece of foreign matter in your gums would have migrated out after 5 years (I think). WAS 4.250 01:41, 28 February 2006 (UTC)
anti-virus backups on different file systems
editSuppose I'd have a computer with both Linux and msWindowsXP installed. These can both use fat. But Linux without special tools (which I will therefore not install) cannot alter anything on ntfs partitions (XP's native fs) and WinXP can not access Linux partitions at all (hell, it doesn't even acknowledge their existence). So if I'd have all my files on a fat partition for normal use (where they can both access it) and regularly make backups on both an ntfs and a native Linux partition (reiser, ext, or whatever). Would my backups then be safe from viral attacks? Assuming a virus is specific to one OS (which is always the case, right?) then it won't be able to alter anything on the non-native file system, right? Or are they accessible, just not in a consumer-friendly way? DirkvdM 11:44, 27 February 2006 (UTC)
- Viruses can always write to the physical hard disk, or "PHYSICALDRIVE" as it is called on MS Windows. I forgot its name but I remember reading about a virus which overwrote random 65KB portions at a raw level to the HDD. This tended to destroy filesystems and, if it got the right place, partitions. So your data on any type of partition isn't completely safe. Mind you, most Windows virus writers are relatively ignorant, so they're only likely to try do anything to the XP NTFS partitions. By the way, are you sure you don't want to install linux-ntfs? It's a good tool. -- Daverocks (talk) 12:31, 27 February 2006 (UTC)
- I haven't tried either myself (I need to get around to backing up my system and reinstalling XP so that searching for files doesn't crash explorer first...) but Captive NTFS looks good as well (external links in the article). Thryduulf 14:11, 27 February 2006 (UTC)
- Ah, so it's a matter of at which level the virus (or whatever) operates. So I do get some protection, but only against the ones that only work at the level of the OS (provided I don't install something like linux-ntfs or Captive ntfs) and not against the ones that bypass that and work at the most basic level. How many are there of each type and which tend to be the most dangerous ones? By the way, the scheme would also protect backups against my own stupidity, as long as I don't work at too elementary a level (which is usually the case). DirkvdM 12:39, 28 February 2006 (UTC)
- You seem really worked up about viruses :) I don't know about others, but I've only ever had about 5 infected files ever walk into my computers, and they've all been zapped by my antivirus... enochlau (talk) 15:11, 28 February 2006 (UTC)
- A warning: we all think we're 1337 Windows geeks and that with two firewalls and an up-to-date virus scanner and a bit of common sense we're immune to virus infection. I learnt the hard way a few days ago when I assumed AVG would take care of this virus that appeared on my hard drive. One almost-wiped-out Windows installation later (which I could only fix by installing a second copy of Windows and using that to clean the first one) and I learnt never to take my geekiness for granted. Sum0 21:01, 28 February 2006 (UTC)
- You seem really worked up about viruses :) I don't know about others, but I've only ever had about 5 infected files ever walk into my computers, and they've all been zapped by my antivirus... enochlau (talk) 15:11, 28 February 2006 (UTC)
- And that was just an OS, which you can re-install. The loss of essential data would be a much bigger pain, to put it mildly. This is indeed one of those things that hardly ever go wrong so we're lulled into a sense of security. But when it goes wrong it can go wrong big time. Same with car accidents (30 million dead and counting). I'm sure my computer is infested woth all sorts of malware and is a time bomb that might never go off. But then ....
- But there's still my question how many (malicious) viruses and such there are that this scheme would not protect against. DirkvdM 09:03, 1 March 2006 (UTC)
- Obviously, it's impossible to give a number of viruses that you are not protected against. I can say that your data is not fully protected as viruses do exist which write physically to the hard drive. Despite this, it would be difficult to get one of these viruses if you have the right protection. Sum0's experience shows us that we are never fully protected even though we think we are, but you should be fine. -- Daverocks (talk) 11:52, 1 March 2006 (UTC)
Those crystallization hand warmer thingies
editOur article explains quite well how they work, but can anybody tell me when and where they were invented? I'm just curious... -- Ferkelparade π 14:41, 27 February 2006 (UTC)
- I had no hope on finding the inventor, but got this really interesting link [[12]] --Zeizmic 17:47, 27 February 2006 (UTC)
Low Density Solids
editIs water the only common molecule that becomes less dense as a solid than it is as a liquid? I'm not interested in freaky lab-produced molecules. --Kainaw (talk) 15:28, 27 February 2006 (UTC)
- No, it's not. See Water#Density of water and ice for a few other substances that are less dense in their solid form than in their liquid form. Acetic acid, the substance that gives vinegar its awful smell and sour taste, is one example. The (non-artificial) elements silicon, antimony, bismuth, and gallium, are also examples. --Bowlhover 23:43, 27 February 2006 (UTC)
- Water's maximum density is at about 4C. Lower than that, it becomes less dense as a liquid. This is important for us up in Canada, because lakes completely 'turn over' as it gets cold (and warm again). There is no common fluid that does this. --Zeizmic 16:30, 27 February 2006 (UTC)
Hair
editHi, I'd like to ask about sthg 1-Whats the function of the hair on our bodies? 2-y is it thicker in some places? 3-If it is useful, y do we remove it?
Thanks Yasmeen
- I just read the article on Hair. It has everything anybody needs to know. :) --Zeizmic 17:32, 27 February 2006 (UTC)
Kinetic energy in relativity
editIs it correct to say that: kinetic energy = (mv^2)/(2*sqrt(1-(v/c)^2))
Re-arranged: 1/2 ?m v^2
That is, using the formula for mass being: mass = ?m where m is the rest mass
and substituting it into the formula kinetic energy = 1/2 m v ^2
This gives: 1\2 ?m v^2
or: (mv^2)/(2*sqrt(1-(v/c)^2))
I have checked the articles on special relativity and kinetic energy and can't find what i'm looking for.
If this is not true, WHY NOT?
- It isn't true. Generally speaking, you can't just insert a factor of gamma in front of the mass in a Newtonian formula and get a relativistic formula. Sometimes you need a factor of gamma^3, or gamma^-1, and it can be hard to tell which. Sometimes you need something more complex altogether.
- As for your specific formula, 1/2 ?m v^2, try comparing it to a known formula for the kinetic energy, (? - 1)m c^2. With a little algebra, you'll find that the two are equal only if v = 0. Melchoir 08:40, 28 February 2006 (UTC)
- The formula isn't true because of the way Newton's formula for kinetic energy, KE=(1/2)mv^2, was derived. Kinetic energy is basically the work needed to accelerate a mass up to a certain speed. If a constant force is applied to an object, causing the object to accelerate at a, the object will reach a final speed of v=at after time t. The average speed of the object during acceleration is 1/2 v (where v is the final speed), which means the object traveled a distance of 1/2*v*t during acceleration. Work is equal to force multiplied by distance, so W=F*(1/2)*vt. Since F=ma, W=ma*(1/2)*vt. Acceleration (a) is measured in d/t^2, but d/t^2 times t is d/t. Substituding d/t for a and getting rid of t, we get W=m(d/t)*1/2*v, but d/t is the average speed and can be replaced by v. That is how we get the final equation: W=(1/2)*m*v*v = (1/2)*m*v^2
- As you can see, the equation (1/2)*m*v^2 assumes that, if a constant force is applied to an object, the object will accelerate at exactly the same rate for as long as the force is applied. This assumption cannot be fulfilled. According to the theory of relativity, it will become harder and harder to accelerate an object as its velocity approaches the speed of light. For example, more force is needed to accelerate an object from 299 792 400 m/s to 299 792 450 m/s in one second, than from 10 m/s to 60 m/s in one second. --Bowlhover 17:17, 28 February 2006 (UTC)
Water Droplet formation
editWhy does a water droplet when suspended in freespace form a perfect sphere before losing its shape on coming into contact with a surface? Bob Pollard18:53, 27 February 2006 (UTC)
- Surface tension makes it energetically beneficial to minimize the surface area. Less area means less energy, and a sphere has the smallest area-to-volume ratio. On coming into contact with a surface, what happens depends on the surface. If the surface is hydrophilic (water-attracting), then the attraction of the surface will cause the water to disperse, because it'll have even lower energy on the surface, even if it means higher area. If the surface is hydrophobic (water-repelling) then the drop won't disperse, and you'll be left with a bead of water resting on the surface. --BluePlatypus 19:25, 27 February 2006 (UTC)
- A bead of non-spherical water, to be sure. freshgavinG??? 11:36, 2 March 2006 (UTC)
Thank you for the explanation.
Losing neurons due to a weak hit
editThere's a belief (likely a myth) that if you hit somebody in the head he loses a number of neurons, no matter how strong the hit was, even if it almost didn't hurt the "victim". Is that true?
- This is not true. Your brain is protected by a thick skull and is suspended in Cerebrospinal fluid, both of which act as protection for your brain in the case of mild hits — even those hard enough to raise a bruise or a bump on your head. Harder hits, however, which might cause loss of consciousness or concussion, can indeed damage neurons. This damage may or may not be permanent. See also our article head injury for more information. — Asbestos | Talk (RFC) 21:17, 27 February 2006 (UTC)
- Thank you very much ;)
- For what its worth, adults lose some thousands (figures quoted on the web run as high as a hundred thousand, and I can't be bothered to find something more reliable and precise) of neurons each and every day. It's natural cell death; there's little you can do about it, and there's really little need to worry about it.
- Very mild traumas may push a few neurons 'over the edge', but they get lost in the noise. Still, it's generally better to avoid getting hit altogether. TenOfAllTrades(talk) 01:43, 28 February 2006 (UTC)
Wiki GUI in PHP?
editI'd like to make a wiki-like web page where users could add text and click on words to do things like add links. Would PHP be the best language to do this in? What would you recommend? Thanks!
- I just did this for our water polo club, but I can't figure out what to do with this new baby. Basically, your hosting site (ours is myhosting.com) gives you a Linux account. They tell you how to load up MediaWiki (which is what runs Wikipedia). It's all php, etc. --Zeizmic 22:15, 27 February 2006 (UTC)
- Thanks, but I don't want to use media wiki. I'd like to try to create a gui-based system, where users clicked on words to add media or links. Do you think PHP would be good for this?
- PHP isn't a client-side language. For what you're talking about, JavaScript is what you want on the client side; there is more freedom on the server side. PHP would work, but so would Ruby + Rails, or Python + a decent framework, or practically any language/framework combo. --Sam Pointon 00:40, 28 February 2006 (UTC)
Mediawiki is written in PHP, but it uses a MySQL database to store things. You could feasably write something similar to this in PHP. The downside of PHP is that it's a server side language so everything needs to essentially have a 'submit' button (or a link that does the same thing). — Ilyanep (Talk) 23:23, 4 March 2006 (UTC)
conscious sleep
editOur article notes that "sleep is the regular state of natural rest observed in all mammals, birds and fish. Sleep is not actually 'unconsciousness,' but rather, it is a natural state of rest characterized by a reduction in voluntary body movement and decreased awareness of the surroundings. Therefore, since consciousness is literally the awareness of the surroundings, being asleep is just an altered state of consciousness, as opposed to being unconscious."
Over the past few weeks I've experienced a few episodes of wakeful, conscious sleep. They seem to be 30-45 minutes in duration. I'm aware of my body sleeping and can observe my breathing, heartbeat, and other bodily sensations, including very minute twitches, as well as the myoclonic jerks I've experienced since the time of the first conscious sleep experience. I'm bipolar, and for the past few months have been experiencing the high side. The week during which the sleep experience and the myoclus began was very stimulating (a cruise) and my own perception of the highest point of my current mania is a few days before the sleep experience began.
The experience is definitely not associated with drowsiness. Nor is it at all like lying awake.
I'm receiving treatment from a psychiatrist (long-term) and a neurologist (since the jerks began). But I wonder: what is this conscious sleep? How is it related to the sleep cycle? Could it be a part of stage 1? Have you ever heard of a similar case? --Halcatalyst 23:20, 27 February 2006 (UTC)
- Look at our articles on lucid dreaming and sleep paralysis, if you haven't already. Is that what you're looking for? — Asbestos | Talk (RFC) 23:24, 27 February 2006 (UTC)
- That article on sleep paralysis is fascinating, and seems to fit the description. I'm semi-bipolar (unipolar with cycles), and I just get along with lucid dreams, and intense thought dreams when I was more uncontrolled. --Zeizmic 23:32, 27 February 2006 (UTC)
- Thanks for the references. I've known of lucid dreaming for some time; it's not that. There's nothing dreamlike about the state -- the sense I have is that I'm just there observing. The observation persists through waking, and then I behave as I would during normal wakeup, except that I'm aware of what's going on instead of coming out of unconsciousness. On one occasion, my wife said I appeared to be in deep sleep when she woke me up. Other times, I've awakened on my own. I don't think it's sleep paralysis; it's not at all like what's described there, although "I" do have the sense that my body has to do the waking up, not "me." That doesn't bother "me"; in fact, it makes me feel very happy and relaxed. I can perceive, or I can think about anything I like. Occasionally I've noticed my eyes flicking open, and if there's any light I can see something. But it's not something willed. Another observation: I remember many of my dreams. They're definitely dreams. Lately, they seem to consist of sequences of frustration and are not particularly related to my waking life. --Halcatalyst 00:18, 28 February 2006 (UTC)
- Write down details. And try to get a witness to verify stuff. Misremembering and self deception are big problems in dealing with conciousness. When I have lucid dreaming, thinking too much wakes me up, making me think that's not what you are experiencing. Do experiments to get data, and write it down. you might have some special gifts and be able to provide insight into human conciousness during sleep states. Be aware that conciousness is mostly about laying down memory tracks in the brain where they can be recovered later. WAS 4.250 01:52, 28 February 2006 (UTC)
Thanks to all who responded. --Halcatalyst 14:40, 1 March 2006 (UTC)
Teen Pregnancy
editA few weeks ago, Stephen Colbert (the Colbert Report) reported an interesting story that I haven't been able to find direct reference to anywhere. According to him, teen pregnancy rates are decreasing, and it's because teens are starting to go for oral sex instead of actual intercourse. Is any part of that true? Black Carrot 02:04, 28 February 2006 (UTC)
- "A major analysis by the Alan Guttermacher Institute attributes about a fourth in the decline to delayed intercourse but three-quarters to improved contraceptive use among sexually experienced teenagers." (Harmful to Minors, 112) Raul654 03:46, 28 February 2006 (UTC)
There has been a drastic increase in oral sexually transmitted diseases among teenage girls because of this.
- Only amonst the girls...? --Username132 20:05, 3 March 2006 (UTC)
- A few years back, I saw an article that said certain European countries were promoting oral sex over intercourse instead of the normal abstinence bit. It was on sxxxy.org, I believe. Skomae 04:16, 4 March 2006 (UTC)
February 28
editI want Wikipedia e-mail addres please , then I send my article to you .
editPlease see Wikipedia:Articles for creation. Superm401 - Talk 03:56, 28 February 2006 (UTC)
I expect Help:Starting a new page would be a more useful link. — Asbestos | Talk (RFC) 23:15, 28 February 2006 (UTC)
Ant Farm
editHi. Just wondering a few things concerning an ant farm I am constructing:
- Can ants stand to live in perpetual darkness? My farm will likely be in a locker.
- The only entrance to the farm is a hole I drilled in the top. I am thinking about cutting a long strip of sponge to plug the hole and reach down to the dirt floor. Will a suitable amount of fresh air come through the sponge? Will the ants be able to extract water from the wet sponge or will over-saturating it be necessary (where water drips onto the dirt)?
- I received a small packet of "ant food". It looks like little bits of green stuff, bird seed and misc. stuff. Will any and all types of human food suffice when I run out of "ant food"?
Thank you. Ross Uber - Talk - Contributions - 04:16, 28 February 2006 (UTC)
- You are planning to turn your school locker into an ant farm? Cool. But how will you watch them burrow and do ant stuff? And they are likely to generate some social opprobrium on your behalf if they go foraging, don't you think? alteripse 04:29, 28 February 2006 (UTC)
- Actually, I bought two wooden picture frames, took out the backs and glass, put in unbreakable clear plastic and wood-glued them together. Then I drilled a hole in the top. I got a picture frame mount and some nails. It worked out nicely. I have made it impossible for them to escape the farm. Ross Uber - Talk - Contributions - 04:51, 28 February 2006 (UTC)
- 1 probably. they live underground. 2. Not sure. 3. They seem to love sugar in my ant farm/kitchen. GangofOne 05:05, 28 February 2006 (UTC)
- Actually, I bought two wooden picture frames, took out the backs and glass, put in unbreakable clear plastic and wood-glued them together. Then I drilled a hole in the top. I got a picture frame mount and some nails. It worked out nicely. I have made it impossible for them to escape the farm. Ross Uber - Talk - Contributions - 04:51, 28 February 2006 (UTC)
I see a disaster in the works here. The ants will climb to the top of the sponge, chew through it, and escape. When people put their jackets on they will be full of ants and you will go home black and blue that day. I suggest you buy a proper ant farm from a pet store, they are cheap enough and will be built such that no ants can escape. I don't think total darkness is good for them, either. StuRat 10:57, 28 February 2006 (UTC)
- Just keep them out of my kitchen, that's all I care about. JackofOz 11:26, 28 February 2006 (UTC)
I see a genious at work here. But if you tell too many people at school you'll get shut down before the ants escape. Even one person maybe too many. If you're careful you can keep the ants contained by making sure they can't escape even if it some how tips over. Don't let your locker get stinky. Rubber bands are great in so many ways. A small strip of screening will ensure they have enough air IF your drill hole is large enough. But make sure the screen is very securely attached. God bless duct tape. Have a good look at the commercial ant farms at a store. They've been designed with these kind of questions in mind. My ants died because they didn't get enough water, even though I tried to keep the dirt wet. You might try jamming a medicine dropper with water through another drill hole; but that might present a high escape risk. They love fruit, and it has lots of water, but I don't know if they will need more water than that. They will also eat most other human foods. Remember, ants don't live very long anyway; you'll just need to get more. I don't know if they can live permanently in the dark. I hope you will tell us the end of the story and what you find out. --Leah
This should be in an Archie comic! --Zeizmic 12:46, 28 February 2006 (UTC)
Need to verify an answer on a TMSCA test
edit- Yes, you should always verify your answer before handing in your test. - Mgm|(talk) 09:08, 28 February 2006 (UTC)
Map of Ice Thickness at Last Glacial Maximum
editHello, I need a topo map of the ice depth above what is now the UK (or European or even global map if available) during the Last Glacial Maximum 20,000 years ago. Thanks, - Halidecyphon 10:25, 28 February 2006 (UTC)
Try 20th Millenium BC topographical ice depth charts
Global Warming
editDear all,
Are there any actual evidences of human causing or enhancing Global Warming?
If not, what are the natural causes? Can it be prevented?
Thanks!
- The article on global warming does a pretty good job at answering some of your questions. Have you had a look at it? Dismas|(talk) 11:42, 28 February 2006 (UTC)
Chemical Reactions and the Atom
editDear all,
As you see, in Chemistry lessons, what they teach you are just equations. Can anyone tell me, microscopically speaking, what is actually happening to a reaction? For example, a neutralization reaction, what is actually happening to the HCl and the NaOH? Are the bonds broken and "re-bonded" together? Where do they get this energy?
Secondly, why does electrons revolve around the nucleus? I mean, if you put a negatively-charged metal beside a positively-charged (with the distance of 0 - 5 cm), I mean, the negatively-charged metal won't just go revolving around the positively-charged metal, so why is that?
Thanks for all the time! - Just love science
- The Na and OH in NaOH aren't really bonded to each other, just electrostatically attracted to each other. In water the two separate, since both are attracted to the polar water molecules almost as strongly as to each other.
- The H and Cl in HCl are covalently bonded, but the bond breaks when the HCl dissolves in water. This happens more or less for the same reason: both halves of the HCl molecule are so strongly attracted to the nearby water molecules that they get easily pulled apart.
- In any case, in aqueous solution both NaOH and HCl do not exist as whole molecules, but as ions (Na+ and OH-, or H+ and Cl-, respectively). When you mix the two solutions, the OH- and H+ ions combine to form H2O, leaving you with water containing Na+ and Cl- ions.
- If you evaporate the water, the Na+ and Cl- ions will stay behind. Being oppositely charged, they will be attracted to each other (just like the Na+ and OH- in NaOH) and will stick together to form NaCl. —Ilmari Karonen (talk) 13:23, 28 February 2006 (UTC)
- For the second question, hm...how to best answer this? See quantum mechanics. I have to run, but hopefully some more Wikipedians will come and elaborate. --HappyCamper 14:35, 28 February 2006 (UTC)
- I think the revolution of electrons around the nucleus of an atom is similar to that of a satelite (e.g. the moon) around a planet (e.g. the earth). At a certain speed of revolution, the satelite (moon/electron) is able to constantly fall towards a specific point, which is what causes it to go around and around.
- Your charged metal idea would work if you took it far into space where there is "no gravity" and moved one of the objects at just the right speed. See Orbit - this is about planetary orbit, which is what I learned in Physics but I think it's applicable in this situation too. It's just the graviational forces in the case of planets are electrostatic forces in the case of electrons. The article might be a bit heavy for you though (it's a bit heavy for me anyways).
- Ask your physics teacher if they can explain electron oribtals to you --Username132 16:22, 28 February 2006 (UTC)
Chemistry lessons don't teach what is actually happening in a chemical reaction because that is physics, the behavior of electrons ("psychology of electrons"). Electrons do not revolve around the nucleus. An "electron orbital" is a word meaning a 3-d shape describing the electrons probability of interacting due to its wave nature (its position is not in one point spot, like a wave washing up on the beach is not in one point spot). WAS 4.250 18:51, 28 February 2006 (UTC)
- Chemistry does teach that, once you get past the level of high-school chemistry education. --BluePlatypus 08:23, 1 March 2006 (UTC)
isotopes
editI want to know about some important applications of isotopes cobalt-60, iodine-131, sodium-24 and uranium-235. Thank you.
- Well, I searched for the term "cobalt-60" and found a page for it at, cobalt-60. You might want to try searching for the others as well. Hint: It will narrow down how many you need to look for more info on. Dismas|(talk) 13:25, 28 February 2006 (UTC)
Uranium is used for generation of electricity.
Can cows read clocks?
editIn the question about Chinese time zones lomn put forth the proposition that cows can not read clocks. I dare challenge this. Of course, it there is no clock in the stable (which will usually be the case) they can't, but what if there were? Say, one with just one big clear hour hand? Surely they'd figure out that the hand moves over time (they've got little else to do). And then they'd figure out that it's near the bottom around daybreak. And then they might figure out that the milking starts at a certain position of the hand. In the case of daylight savings, the hand could be slowed down or speeded up over a period of, say, a week, giving them the feeling nothing much has changed. Pavlov's dogs reacted to a bell. Why couldn't cows react to a clock? DirkvdM 13:41, 28 February 2006 (UTC)
- First of all, of all the things in the barn that move on a day to day basis, why would a cow even know to look at a clock. Secondly, animals just seem to know what time it is. I'm not saying that a cow is smarter than any of my dogs although my dogs are able to tell me within 5 minutes +/- when their dinner time is. So why would a cow need a clock? Dismas|(talk) 13:51, 28 February 2006 (UTC)
- Ah, but that's their biological clock. Suppose you erased all other indications of time (particularly sunlight) would the cows then start to use the clock and could you make them believe that over their biological clock and thus manipulate them? Of course artificial light would do that too, but that would be too obvious. I'm just curious if one could teach cows to read the clock. Most people would agree that they can't but I'm sure they can, so that would be an interresting experiment. Of course that would be easier with, say, rabbits, but cows start lactating at a certain time of day. Or do other (small) animals do that too? I suppose they do. DirkvdM 20:17, 28 February 2006 (UTC)
- You may not consider this relevant to the original question but your comment of "cows start lactating at a certain time of day" set off bells and whistles in my head. Cows don't care what time it is. The idea that cows can only get milked at dawn or some other set time is wrong. A great number of dairy farms, in the U.S. at least, milk their cows twice a day. It is because of the production of milk by the cow throughout the day and the size of their udder that it's essentially required that the cow get milked at least every 12 hours. Otherwise the cow starts to become uncomfortable with the heavy weight of all the milk in its udder. Afterall, in the wild a calf would be drinking from this supply throughout the day and not letting it get too full.
- There are also a number of farmers that milk their cows three times a day. There are advantages to this but most farmers simply don't have the man-power to be in the barn three times a day milking while other things on the farm need to be done as well.
- And as far as the times at which the cows are milked, while it's true that many farmers will milk their herd near daybreak, it's not a biological necessity. I know of a few farmers who milk their cows starting between 1 and 3 a.m. They do this because that schedule happens to just work for them.
- Then there are the robotic farms. Some farms have robots that open a gate to let cows in one at a time, milk them, then release them back into the herd. The cows go in when they feel like it and the RFID tag around their neck lets the robot know which cow is in the machine. A laser guided milker attaches to the teats and milks the cow. While this is taking place the cow is fed a little grain to keep it busy. So at these farms, the cows and not the farmer establish their own schedules of when they get milked. And again, it's not always at dawn. (On a sidenote, I don't see an article right off the bat about robotic milkers... I may just write one)
- So, anyway, that's probably more than you wanted to know or maybe you already knew some of that and I just took the comment you made the wrong way. But it at least adds a bit of info to the experiment of teaching a cow to read a clock. Dismas|(talk) 01:43, 1 March 2006 (UTC)
- Ding Ding! This wins the silliest thing of the week award! Collect your Suitly Emphazi medal at the door. --Zeizmic 22:37, 28 February 2006 (UTC)
- I have covered this in multiple research papers on AI. It is a minor topic in my studies, but I think it is a very important one. When asked if computers will ever have true intelligence, I reply that we must teach them to understand time first. So, going back to the question here... I continually pester animal experts about an animal's concept of time. What actions do they perform that show they recognize a past, present, and future? Can those actions be explained without a requirement to understand past, present, and future? For the most part, animals show no comprehension of anything but the present. They know cause and effect, but they don't understand something like "I'll give you some food tomorrow if you work extra hard today." It has to be rather immediate cause and effect.
- There are some things that show some understanding of a future. Squirrels bury nuts in the fall to prepare for the winter. So, they must understand that the winter is coming, right? I easily found many studies on squirrels and their nuts. It is a biological thing. One study went so far as to determine the chemical released in their body that made the brain have a sudden OCD thing about hoarding nuts. Then, I spent a long time begging for info on apes. They are similar to us, so they must understand time. Even the ones who learn sign language show no understanding of anything but the present. You can't tell them you will give them something tomorrow because they don't understand it.
- So, cows are rather low on the IQ scale. If some attention getting event happened at a certain time every day, they would learn that the event happens at that time every day. However, a moving hour hand is not very attention getting. So, it is very doubtful that they would ever relate a position of the hand to an event.
- An anecdote on animal behavior and time. A study used a bird in a box. Every 5 minutes, the bird would get food. So, the bird should learn to wait 5 minutes and the food will come out. After a few days, the lid was taken off the box and the bird was watched. It would turn three times to the left. Bounce twice. Turn four times to the right. Bounce three times. Back up. Step forward. And then chirp. After doing this pattern slowly over a 5 minute period, food came out. Then, the bird did it all again exactly as before. The bird didn't learn time. It learned that it had to do this funky series of movements to force the food to appear. --Kainaw (talk) 01:30, 1 March 2006 (UTC)
- I didn't say cows would understand the concept of time the way we do (!), just that it could use a device we use and thus understand that. Make it a small animal (mice are popular for that reason) and make the clock really simple and big and the only thing they get to see. Wouldn't it be cool to be able to say you taught an animal to read the clock?
- Btw, in your comment I taste something that I often encounter, namely that the intelligence of an animal should be measured by human means. Like we're the summum of anything to do with intelligence and other animals can only hope to achieve our level. A favourite experiment of mine was when a pigeon was given food when it pressed the right button. First it was presented with two paintings with different types of painting styles and it had to pick the expressionist painting (or whatever). At the same time a class of university students were presented with the same problem. Both the pigeon and the students got this one. Then came a series of paired graphs, one going up and one down. The students got this, the pigeon didn't. Ah yes, of course, pigeons don't get such an abstract thing. Then came another series of graphs. Which the pigeon got. But the students didn't. The difference was simply the surface below the graph. Also an abstract thing, but still the pigeon beat the humans. (Actually, the pigeons reacted to how much red (or whatever) was visible in the images, but still pigeons beat humans in a human test. How would we do in a pigeon test? And who would then have to devise that? Can we ever know?)
- Tricky follow-up question. Are there humans who can't read clocks? (IQ 50 perhaps?) DirkvdM 09:29, 1 March 2006 (UTC)
- Unfortunately, behaviour like nut burrying does not proove a concept of the future. I bite my nails, but I don't do it out of an understanding that if I don't, in the future they will get so long that I will poke my eye out - nut burrying is an instinctive (or perhaps learned) behavior that tells us nothing about the animal's ideas about time. We could, of course, train a cow to respond to a clock being at a certain time, as long as it could distinguish the two stimuli (clock a and clockb).
- I've heard that, with the advent of digital clocks, fewer young people know how to read an analog clock face. Not that I blame them, it certainly took us a lot of work to learn that. Black Carrot 23:57, 6 March 2006 (UTC)
- Forgive me for my ignorance, but what does suitly emphazi mean? --JianLi 05:08, 7 March 2006 (UTC)
- It's a joke on a questioneer who used those words, probably intended to mean 'suitably emphasize'. The term since stuck as an in-joke at the ref desks. DirkvdM 11:21, 7 March 2006 (UTC)
google mail
editI would like to know how gmail manages to increase the memory space every day. How is that posible. Any information provided will be appreciated.
- While not "every day" our article on Gmail states the following:
On 1 April 2005, exactly one year after the initial release, Gmail increased the mailbox size to 2 GB (advertising it as 2GB plus) and introduced some other new features, including formatted editing (giving users the option of sending messages in HTML or plain text). As of February 2006, the mailbox size is 2.63 GB, and is increasing continuously at a rate of approximately 10 MB per month.
- My guess as to how it's possible would be money. They see a need to stay ahead of Yahoo and others so they keep throwing money into newer and bigger servers. Dismas|(talk) 14:35, 28 February 2006 (UTC)
- A more direct analogy would be network providers selling service like 5/1 mbit when there's no way the total pool of subscribers has access to that if they all tried at the same time. It's called oversubscribing or overselling and its a very common practice as part of 'Economy of Scale'. On this network comparison, it dates back to the days of dialup where there were typically 10 users to every 1 modem (or maybe 8:1 or lower if you had a real good service). Sure, there would be a huge problem if every single user wanted on, but they rarely did. It probably existed in some form for the better part of written history, as your banking example shows, it is a tenet of our capital economy. I couldn't find any relevant articles on this, which I am suprised at since it's a very common and (imho) interesting subject.
Back on to the subject, what would happen if everyone tried to fill their inboxes. I think that one of two things would happen, google would rescind their offer of 2+GB and say 'oops sorry you only get 75MB' which they are entitled to do, its a FREE service after all. The other option is that the clever lads they are, they figure out what everyone is up to and come up with a way to aggregate the data (for ex. if you tried to fill it by sending huge attachment mails around, they would simply soft link the email so that 100000 copies in different inboxes only cost 1 worth of disk space). As far as your lawsuit goes, good luck with it, hopefully you get all your subscription fees back!
- A more direct analogy would be network providers selling service like 5/1 mbit when there's no way the total pool of subscribers has access to that if they all tried at the same time. It's called oversubscribing or overselling and its a very common practice as part of 'Economy of Scale'. On this network comparison, it dates back to the days of dialup where there were typically 10 users to every 1 modem (or maybe 8:1 or lower if you had a real good service). Sure, there would be a huge problem if every single user wanted on, but they rarely did. It probably existed in some form for the better part of written history, as your banking example shows, it is a tenet of our capital economy. I couldn't find any relevant articles on this, which I am suprised at since it's a very common and (imho) interesting subject.
- I have a feeling that the actual amount of available memory would be less - not all mailboxes use up their allotted memory - they just need to provide a service which gives the illusion that the particular amount of space posted is available. As long as they can do this, it is not necessary to actually have that amount of memory available. Think of it this way as an analogy: banks do not have enough money available for every one of their customers to spontaneously take out their money. However, as long as they can provide the money every time it's requested, there's no problem with that. --HappyCamper 14:42, 28 February 2006 (UTC)
- Thats a really interesting thought. What would happen if everyone tried to use all their memory. Could we sue google for it? I would like a gmail account, but its still in beta. Does anyone know when it starts properly, and will anyone invite me?--Bjwebb (talk) 15:48, 28 February 2006 (UTC)
- Sure, I have 100 invites. Ask on my talk page. And I think you're right, we could sue Google if that was the case. Even more interesting is if everyone decided to get their money in cash at the same time. The system would collapse! ? ?i?ff?? 18:16, 28 February 2006 (UTC)
- And so it did. What resulted was the great depression. DirkvdM 20:20, 28 February 2006 (UTC)
- Good idea. Do you want me to send you the Wikimedia database dumps? ;) --Optichan 17:16, 1 March 2006 (UTC)
- Well, just me wouldn't be enough. Why not send them to every single G-mail user :)--Bjwebb (talk) 17:23, 1 March 2006 (UTC)
- No, you could not (successfully) sue Google. The TOS states that "Google may, in its sole discretion, modify or revise these terms and conditions and policies at any time, and you agree to be bound by such modifications or revisions." Superm401 - Talk 04:02, 6 March 2006 (UTC)
A good way to insulate aluminium
editHi, I have gotten my A-level coursework today for physics, and I need to find the specific heat capacity of aluminium. The problem is that I need a suitable material to insulate it from the air, otherwise I will end up supplying more energy to the metal than the true value. What is a suitable way of insulating an aluminium cylnder from the air? It needs to be something available in a secondary school science lab. Thanks. --Krackpipe 18:19, 28 February 2006 (UTC)
- Yeah, you made it up to A levels! (Whatever that means.). Having got this far, it is good to learn how to research. There's some stuff in this encyclopedia, but for real A-level pros, there's Google. I put in 'determine specific heat' and this is the very first hit [[13]] It's for copper, but a little bit of paint could change it to an aluminum colour. --Zeizmic 18:38, 28 February 2006 (UTC)
- Like you said, for people without A levels there is Wikipedia, which can tell you just what an A level is. Apparently there may also be something like a B level. But a C level only seems to exist with a hyphen. No D levels, sorry. DirkvdM 20:27, 28 February 2006 (UTC)
- Nope, but there are O levels, which are related to A-levels. --BluePlatypus 06:40, 1 March 2006 (UTC)
- Like you said, for people without A levels there is Wikipedia, which can tell you just what an A level is. Apparently there may also be something like a B level. But a C level only seems to exist with a hyphen. No D levels, sorry. DirkvdM 20:27, 28 February 2006 (UTC)
- There WERE O levels. They were replaced a long time ago with something called GCSEs...
- Thanks, this page is useful, and I will do some more digging around on google--Krackpipe 19:19, 28 February 2006 (UTC)
- If going to a home supply superstore (Home Depot, Lowe's) and buying pipe insulation is not an option, and assuming you don't want to pilfer the insulation around the hot water pipes in your lab, you might be able to cobble together a few styrofoam hot drink cups for this purpose...--Mark Bornfeld DDS 18:40, 28 February 2006 (UTC)
- Thank you, I was considering using the stuff that goes around the pipes in my loft, I guess that is what I will end up using for the investigation. --Krackpipe 19:19, 28 February 2006 (UTC)
- If you steal the pipe insulation in your loft, the best thing to do is to take it from the cold-water pipe right above your bed. --Zeizmic 22:30, 28 February 2006 (UTC)
- Personally, I wouldn't worry too much about insulating it from the air. I don't think you're expected to set any records for precision. Just note it as a source of error, and you could perhaps do an estimate of the effect of not insulating from the air. Even in a vacuum you'll be losing energy by radiative heat. --BluePlatypus 06:43, 1 March 2006 (UTC)
The idea of everyone using up their gmail space might seem plausible, i saw something but just a glance on the web about using ur gmail for storing files and stuff. I think if 60-70% of the subscribers find that tool very handy in a couple of mmonths we might be able to see what google really were doin.