Wikipedia:Reference desk/Archives/Science/2009 December 26

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December 26

Is galactic red shift not really the Big Bang singularity’s time-dilating effect?

Long ago (in high school) I wanted to be an astrophysicist before circumstances forced me into engineering, but I try to track some of the issues from a layman’s viewpoint. If light heading into a gravity well is blue-shifted (just read this on Wikipedia), and that which is coming out is red-shifted, what else can one make of the red-shift of light from distant galaxies apart from conjecturing an expanding Universe alone? ‘Long ago’ and ‘far away’ mean the same thing, yes? This means that for all practical purposes the Universe from all standpoints is surrounded by its Beginning, which is the Singularity that preceded the Big Bang. Could it not be that the red-shift we see in light from so-called receding galaxies is rather due to the fact that the light is climbing out of a gravity well at whose bottom lies the Singularity? I don’t know what the relation between red-shift and gravitational intensity is, whether it follows the R-squared rule of gravity or not, but I suspect that the Hubble Constant is an outcome of the interplay of this relation and the effects of ‘Singularity Gravity’ (to coin a phrase) on space-time. It is not really so much that the distant galaxies are receding faster and faster as that WE are much farther from the Centre than they are. After all, they are younger than we are as they are closer to the centre. The red-shift we see is ours more than it is theirs. Our spectrometers have departed farther from what they should have been nearer the time of the Big Bang. Of course we are at this distance because the Universe is expanding, but need it be in an accelerated fashion? Coming to think of it, the speed of light must have been changing all the time since the Big Bang – in all neighbourhoods. Either that, or what we now call a metre (meter) has been stretching out as we moved away from the Centre of the Universe….. I have no means of presenting my thoughts in the form of a question as such. I would appreciate a critique of my reasoning so I can see where I can reorient myself. Capping it all is the vexing problem for me of measuring distances to objects that are really in the past. Where are they now? Can we say that because they are still within the light cone then they do exist as we see them until they go over the cosmic event horizon back into the Big Bang black hole? Havanyani (talk) 01:37, 26 December 2009 (UTC)

I cannot answer all of your questions, but why do you think the initial "centre" of the big bang was a black hole? Standard physics expects the speed of light to be constant, but there is a varying speed of light theory that has not acquired much acceptance from the scientific community. Redshift can also be seen in a galaxy within the side that is rotating towards us, but this effect is only noticeable in nearby galaxies. If the universe is infinite, one idea is that the "surface" of the "outside" would have no curve, meaning the universe is flat. However, there's another idea that it could have a negative curve and be "saddle-shaped". This would allow for the "centre" of the big bang to line the "outside" of the curve, but otherwise there is no centre of the universe, and the big bang as an object cannot be located. So there is no "edge" of space, as the visible "horizon" of the visible universe is not the limit of the actual universe itself, although we cannot see beyond that barrier. I'll let someone else answer this before I get too confusing. ~AH1^(TCU) 02:29, 26 December 2009 (UTC)

Not sure I can follow the OP's train of thought, but one thing the OP seems to be grasping at is the fact that gravitational redshift is indistinguisible from motional redshift; that is we cannot tell the difference between gravitational acceleration and other forms of acceleration. Einstein himself called this the Equivalence principle, and it was part of general relativity, which actually deals with MOST of what the OP is talking about. --Jayron32 04:48, 26 December 2009 (UTC)

The act of Sex

Is there a religion in which it is believed and practiced that the act of sex between a male and a female is sacred? 71.100.6.153 (talk) 01:44, 26 December 2009 (UTC)

Quite a few of them, in fact. The LDS Church teaches that sex should only occur between a legally married husband and wife, and that the powers of procreation are sacred and a gift of God. I know many other Christian churches also teach something similar. ···日本穣^? · 投稿 · Talk to Nihonjoe 02:40, 26 December 2009 (UTC)

To take it to an extreme, there have always been cults in the Western world that have had sacred sex. Consider the very cultish Children of God, which openly used prostitution to proselytize new members. See also Sacred prostitution which covers MANY such movements dating back thousands of years through many cultures. --Jayron32 04:39, 26 December 2009 (UTC)

I guess you mean Flirty Fishing, while some of their other (former?) practices involving children are disgusting, I personally find Children of God (cult)#Loving Jesus funny particularly the proscription for males Nil Einne (talk) 08:09, 26 December 2009 (UTC)

"TFI continues to stress the imminent Second Coming of Christ"... Nimur (talk) 12:56, 26 December 2009 (UTC)

If you are are willing to add the word "married" to your question, then Judaism believes so. In fact it is considered one of the holiest acts, because it is the only one that can cause the spiritual (a soul) to be embedded in the physical (the body). Nothing else can do that. (And just like it can be the most holy, it can also be the most un-holy.) Ariel. (talk) 00:26, 27 December 2009 (UTC)

Interesting... perhaps then that is how I should have framed the question, i.e., what criteria makes the act of sex either holy or unholy in various religions? 71.100.6.153 (talk) 01:59, 27 December 2009 (UTC)

Cult leaders often tell their female followers that. 67.243.1.21 (talk) 03:28, 27 December 2009 (UTC)

The sexual act or "Great Rite" is the central sacrament in Wicca and allied neo-Pagan Paths. Usually it is performed only symbolically (by placing the black-handled knife or 'athame' into the cup or chalice), but on special occasions it may also be performed in actuality by the High Priest and High Priestess of the Circle (aka "coven") who are presumed to invoke the God and Goddess respectively within themselves while doing so (and who are usually a married/handfasted couple). Some Circles' initiation of new members (usually after at least a year of probationary study) includes having them perform the Great Rite with the High Priest or High Priestess as appropriate, but this may be done in private with only the two participants knowing if the performance was symbolic or actual. Note that Wiccan ceremonies do not involve all of the Circle's members (all of whom are themselves Priests/Priestesses, hence the 'High' used for the Ceremony's or Circle's leaders) having sex, and the tradition of some Circles of working 'skyclad' or nude has no sexual connotations.

Note also that all of this brief description is a generalization, since every Circle follows and develops its own Path, so some details may not be applicable to a given Circle. 87.81.230.195 (talk) 03:06, 29 December 2009 (UTC)

Mystery red plant between Incheon International and Seoul, Korea

I've been wondering for years about what this plant might be, but I've never found anything about it. I found a picture of it here, but it's not a closeup picture. It grows all over in the sandy marshes between Incheon International Airport and Seoul. Any help in identifying it is appreciated. ···日本穣^? · 投稿 · Talk to Nihonjoe 02:37, 26 December 2009 (UTC)

That's a beautiful picture! Can you discribe the plant a little, height, flower type, etc.? Gandydancer (talk) 04:17, 26 December 2009 (UTC)

I wish I could as that would make it easier to identify. As it is, I've only seen it as close as you can see in the picture, and I've wondered about it for almost nine years now. ···日本穣^? · 投稿 · Talk to Nihonjoe 04:55, 26 December 2009 (UTC)

It sounds like this is something very dear to your heart and I hope you can find the name. Are you from Korea? I'm pretty familiar with most of the plants in the US and the only one here that I know to grow in such profusion in sand at ocean's edge is "ice plant", but it is a succulent and you mentioned marshland. It is here: http://en.wikipedia.org/wiki/Aizoaceae Gandydancer (talk) 05:39, 26 December 2009 (UTC)

Not really dear to my heart, just piqued curiosity. When I can't figure something out, it just bugs me. No, I'm not from Korea, though I am interested in many things about Korea. As for it being marshland, I was just guessing that's what it was since it's right by the coast. Does that plant turn red at any time of the year? ···日本穣^? · 投稿 · Talk to Nihonjoe 05:55, 26 December 2009 (UTC)

I've never been to Korea and from the picture it is hard to tell if that is sand dunes or marsh land. If it is sand dunes, a succulent would be a good guess. Yes, in bloom it would look like the picture. Gandydancer (talk) 06:07, 26 December 2009 (UTC)

It could be salicornia. Here's a photo of the salt marshes near where I live that shows the reddish color of salicornia in the winter [1].--Eriastrum (talk) 23:31, 26 December 2009 (UTC)

I think you nailed it! Just curious, where do you live? Gandydancer (talk) 04:30, 27 December 2009 (UTC)

At a guess in or near Morro Bay, California? Nil Einne (talk) 10:10, 27 December 2009 (UTC)

The only problem being that these plants are red in summer (late July, early August). ···日本穣^? · 投稿 · Talk to Nihonjoe 19:24, 27 December 2009 (UTC)

I do indeed live near Morro Bay on the central coast of California. The salicornia does start to turn reddish in the late summer and fall; it is reddish throughout the cooler months.--Eriastrum (talk) 20:48, 27 December 2009 (UTC)

What causes our windup toy to spark, and what are sparks?

My grandson got a windup toy for Christmas today. You wind it up and that makes a bar rotate over a flat, round circular surface. Two small spokes hang down from the bar and rapidly circle the flat plate producing sparks. We are guessing that the two spokes are flints and that the circle, which looks like sandpaper, is a steel sandpaper. Then we got into a discussion about what was needed to produce...sparks? (we weren't sure exactly what we were trying to "prove"...). At any rate, we came up with oxygen, heat (from friction), and a 3rd thing, and I'll be darned if I can remember what it was. Any thoughts on this process would be most welcome. We did wonder if there is a little heat in the sparks, and we guess that there is, since I know that they can be used to start tinder.

The discussion went on to "exactly what is a spark?", and is this process similar to the (I think) electron transfer that causes the little shocks that one occasionally experiences in a dry atmosphere when rubbing two things together. Is there "heat" in those shocks?

Sorry for the very poor explanation - my physics knowledge is very limited. Gandydancer (talk) 05:06, 26 December 2009 (UTC)

Oxygen, heat (source of ignition) and.....FUEL (something to 'burn', though oxidation may be technically more accurate), See also Fire. Your flint and 'sandpaper' hypothesis sounds very likely.
A spark (from a fire or flint) would be a tiny piece of fuel that is in fact burning (educated guess only!). In you second para ("little shocks"), you are referring to static electricity, not the same as the toy sparks. Though static is same as the 'sparks' from a 'trigger' type gaslighter. see Piezoelectricity. (both electricity, though produced by different processes)
Heat?, yes there would have to be though it occurs so quickly you can't feel it. Lightning is also static electricity can be extemely hot, though only for perhaps microseconds (thousandths of a second) --220.101.28.25 (talk) 05:37, 26 December 2009 (UTC)

More accurate definition of Spark "A spark is a small airborne ember or particle of red-hot matter." ie. doesn't have to be actually burning--220.101.28.25 (talk) 05:48, 26 December 2009 (UTC)

... consequently, oxygen is not needed for sparks to form. However, sparks in an oxygen environment can result in flame. Nimur (talk) 13:01, 26 December 2009 (UTC)

Yes, so it appears, though usually oxygen would be present. Most sparks seen would be coming from a fire, though in this case (original question) they are produced from friction, similar to a grinder. Be interesting to see a grinder used in a nil oxygen(vacuum?) environment See also Ember, which may put a slightly different slant on it. --220.101.28.25 (talk) 14:00, 26 December 2009 (UTC)

Some delicate machining work takes place in a nitrogen- or argon-flooded work area, to minimize chance of flame. The metal flakes kicked out during machining do still glow (from blackbody radiation, which does not require flame). Systems which will eventually store pure (~100%) oxygen or other strong oxidizers are specially checked for metal burrs, flakes, or any other tiny metal particles, because the ability to spark just by shaking around these tiny flakes (e.g. steel-on-steel collisions or friction resulting in sparks) may result in fire, if the atmosphere is very highly oxidizing. The fuel source can be the steel particle itself, which can burn in the presence of oxygen. This cleaning procedure, along with other cleaning to remove any flammable fluids or hydrocarbon lubricants, is part of what rates a system as "oxygen clean" - i.e., reduces the risk of spark ignition and flame, when oxygen is added. The OP's discussion of "a 3rd thing" is in reference to the Fire triangle. Sparks are the ignition, not the result, of fire. Only in unusual cases (such as those I mentioned) can the sparking material itself also be the fuel for the fire. Again, keep in mind that the only things necessary for fire are fuel, oxidizer, and ignition - normally, we take the oxidizer for granted, because we are in Earth's atmosphere. But flame can still exist, for example, in underwater welding or in the vacuum of space, if we bring the oxidizer with us. Hypergolic fuels provide chemical self-ignition, and combust without any spark to ignite them. Nimur (talk) 14:37, 26 December 2009 (UTC)

Sparks can certainly be the result of fire. I once burned an aluminium lamp socket, by accidentally shorting it. It made a fountain of very very bright white sparks about 6 feet high. A spark is burning metal, so it's fuel and ignition at the same time. (A spark can also be electrical.) Ariel. (talk) 00:40, 27 December 2009 (UTC)

I am reading everything and thank you! I have looked at the links provided and looked at spark plugs and flintlocks as well. I have begun to rule some things out, however I am still far from an explanation. Certainly one problem is my problem with a poor understanding of physics. As time permits I will try to come to an understanding of where I am at. Again, thanks. Gandydancer (talk) 18:15, 26 December 2009 (UTC)

There are two kinds of sparks. One is electrical, like a static shock, or a spark plug. The other is burning metal. Electrical sparks are blue (in normal air anyway), and metal burning is various colors, including blue, but usually red or white.

Contrary to assumptions, when you rub metal in a grinder, it is not the heat of friction that causes the sparks, but rather tiny pieces of metal that break off, and burn in air. Most metals are flammable. Aluminium is extremely flammable, and iron too - they are just pretty hard to ignite. You can see iron burn, by using fine steel wool - you can light it with a match. And aluminium is burned in the space shuttle. Both simply need a lot of air to burn, and by making tiny pieces you have a large amount of air relative to the surface area of the metal, and it burns.

The reason iron does not normally ignite, is that when the surface rusts (aka burns) it releases some heat, but the heat is absorbed in the mass of the metal, and it never gets hot enough to get going. Aluminium protects itself with a surface layer of alumina, that is very hard, and seals the metal from any additional air. Ariel. (talk) 00:36, 27 December 2009 (UTC)

I have nothing to add to Ariel's excellent answer but my name compels me to contribute to this thread, so I will confine myself to complaining that we seem to be lacking an article here. Spark is a disambiguation page and has no article listed that really covers this meaning, ember really refers to wood or coal fires. There is, however, spark testing which has a section that explains about metal burning (see spark testing#Compressed air method). SpinningSpark 01:37, 27 December 2009 (UTC)

Arie, you say "Contrary to assumptions, when you rub metal in a grinder, it is not the heat of friction that causes the sparks, but rather tiny pieces of metal that break off, and burn in air." So in our toy, the flints move over the metalic surface flicking off tiny chips of metal (the fuel), and in the presence of ozygen they will burn (oxidize). And the friction is needed to heat the metal to its burning point? Say, thanks for that spark test page! I'll check out the toy tomorrow and see if we can ID the metal. I think the kids will enjoy that, and of course I will as well. Gandydancer (talk) 04:00, 27 December 2009 (UTC)

Coughing while asleep?

Last time that I was ill, I had a cough that could be heard through the (admittedly, rather thin) wall and door for my bedroom. Others in the house reported that I sometimes coughed in the middle of the night, even on nights during which I had no memory of waking up. Is it possible to cough while asleep, or is it more likely that I was awake for such a short time that I didn't remember it in the morning? Nyttend (talk) 05:50, 26 December 2009 (UTC)

I don't see why not. Sleep covers a wide range of neurological states, some much deeper than others. People certainly move while asleep (tossing and turning, for example), so I don't see why in some of the lighter stages of sleep you would not also cough if your airway was irritated. --Jayron32 06:29, 26 December 2009 (UTC)

Both sound equally likely to me. You can do a lot that you don't remember during brief waking periods at night. Vimescarrot (talk) 11:49, 26 December 2009 (UTC)

Also, this could explain you being more tired in the morning due to lack of REM sleep if you're only sleeping lightly all night due to the coughing. ···日本穣^? · 投稿 · Talk to Nihonjoe 16:49, 26 December 2009 (UTC)

what is the evolutionary advantage of appreciating natural beauty?

It is almost instinctive to like a vista, grand views, rushing rivers, the smell of flowers, green leaves... well maybe it's advantageous to prefer forests over deserts, but even humans find deserts beautiful sometimes. Ignoring the issue of appreciating the beauty of the opposite sex, why would an appreciation for beauty evolve at all? John Riemann Soong (talk) 06:06, 26 December 2009 (UTC)

Our article Aesthetics is related and will be of interest, though it is a philosophy article and not an evolutionary biology article. Comet Tuttle (talk) 06:43, 26 December 2009 (UTC)

I have a hypothesis that it's due to the brain getting new patterns, because obviously beauty can go stale. --Ayacop (talk) 07:49, 26 December 2009 (UTC)

I am a person that does a fair bit of natural beauty hunting and I'm not sure that appreciation for natural beauty is an evolved trait at all. One could easily argue that it is the result of environment rather than hereditary. If it is evolved then it might not have been caused by direct evolutionary pressure but as a by product of something else. Noodle snacks (talk) 08:35, 26 December 2009 (UTC)

But what would the trait piggyback on? John Riemann Soong (talk) 09:14, 26 December 2009 (UTC)

I don't think that hard science can explain it. It seems to me that one must go into the realm of Noetic Science http://en.wikipedia.org/wiki/Noetic_sciences for an explanation, but most people are not willing to go there. Gandydancer (talk) 18:08, 26 December 2009 (UTC)

The visual beauty you refer to utilizes the sense of sight in a special way. The satisfaction one experiences may be not so much linked to the external stimuli but to the sensation of the functioning of one's visual apparatus. Sight is highly developed in humans in various ways. Expansive vistas of nature illuminated by sunlight allow for a full exploitation of our visual capabilities. This situation might be compared to having a car that can go 400 mph and finally finding a place to utilize that ability. I don't know why there would be pleasure associated with viewing these vistas. But it may be a pleasure just relative to settings that use a far narrower range of our abilities. I doubt if people who live amidst a breathtaking setting are constantly appreciating their view, at least not in a way that they are keenly aware of. Bus stop (talk) 00:04, 27 December 2009 (UTC)

The question carries an implicit assumption that perception of beauty is a function that gives a survival advantage, like having an opposable thumb. IMHO perception of beauty is a survival confirmation only.Cuddlyable3 (talk) 00:13, 27 December 2009 (UTC)

Some things we find beautiful are beneficial things - fertile rolling green hillsides, for example, are likely to contain lots of good food and shelter. I'm not sure how relevant that actually is, though, since it doesn't universally apply. Barren wildernesses are often considered beautiful, and I would think they were best avoided. --Tango (talk) 00:24, 27 December 2009 (UTC)

I believe I have heard someone, I think in National Geographic Magazine, of about a year ago, describe deserts as the most beautiful of places. Bus stop (talk) 00:28, 27 December 2009 (UTC)

Why does wanking feel good? I'm pretty sure our consciousness combined with some formerly advantageous traits can have spurious results. —Preceding unsigned comment added by 92.17.229.48 (talk) 00:52, 27 December 2009 (UTC)

Even fish can have fetishes (sticklebacks I think). 67.243.1.21 (talk) 03:26, 27 December 2009 (UTC)

Also, on the same topic, if one is indoors for a day or two or three, and then one emerges into a not at all spectacular environment — it may look beautiful. If it were merely an urban or suburban setting of no noteworthy natural vistas, but merely say, a sunny morning, after a rain — the glistening objects, however banal, could be of breathtaking beauty. This once again shows that the appreciation of natural beauty is a relative thing. Compared to being in a dimly lit indoor space for three days, any kind of outdoor space in sunshine would be aesthetically pleasing. This also illustrates that we get used to the breathtaking aesthetics of nature, and fail to see it. But I think it has to do with the full utilization of our senses. In a dimly lit room the eyes have limited opportunity to do all that they are capable of doing. This is just conjecture, or original research. Bus stop (talk) 19:01, 27 December 2009 (UTC)

Bear in mind that perceptions of visual beauty are not necessarily even cultural, let alone human, universals, nor are they fixed in time within cultures. For example, most modern Europeans find the vistas of the Alps majestic and uplifting, but before the 18th century Romantic movement they were considered frightening and depressing. 87.81.230.195 (talk) 02:30, 29 December 2009 (UTC)

does MSG change taste with pH?

Other than the change in taste caused by vinegar, etc. Does glutamate that is +1 or at the pI taste differently than glutamate at -1? Would -2 glutamate (e.g. I add baking soda to MSG) smell like fish? John Riemann Soong (talk) 09:18, 26 December 2009 (UTC)

Help someone? I really can't find it in the literature, and otherwise I think I'll end up experimenting to find out. (Though I don't think I can add enough baking soda to get to deprotonate the amino group....) John Riemann Soong (talk) 07:08, 27 December 2009 (UTC)

Problem with Japanese appliances in European plugs

Hi, I'm trying to charge my Japanese Nintendo DSi (for the plane ride home of course!) in Ireland, and I'm having trouble. I have the proper prong converter and a voltage converter that works for Canadian appliances, and every other Japanese piece of electronics that I've brought with me (though admittedly I don't have anything as heavy duty as the DS), but the DS is non-responsive. At most I get a single flicker of the charging light when I plug it in, but it won't be charged at all after an hour plugged in. The DS works (for a couple of seconds before the battery goes flat) so I'm convinced nothing's been burned out, and I charged it fine just 3 days ago (in Japan), so I'm lost as to why I wouldn't be able to charge it here. Does anybody know of any reason why I might be having this problem? Thanks! 83.71.33.178 (talk) 09:31, 26 December 2009 (UTC)

It's not really possible to diagnose your problem without having the equipment in front of me to test but here are some possibilities. First off, without checking with a meter, you cannot be sure that your converter is providing the right voltage. Many charger circuits nowadays are "universal"; that is, they will accept a wide range of input voltages. They will consequently still charge even if you have not provided the voltage you think you have. If your DS is not "universal" the difference is explained. A more likely explanation is that there is a fault with the connection cable between voltage converter and DS (do you use the same cable for any other piece of equipment?). The brief flicker of the charging light would seem to indicate a fault, either with the cable, or worse from your point of view, with the circuitry in the DS. That kind of brief flicker is often indicative of something that has gone open circuit, you still get a brief burst of current through capacitive coupling when first connected. SpinningSpark 10:48, 26 December 2009 (UTC)

Yeah, the brief flicker was suspicious to me too, so I checked with the exact same combination of voltage converter/prongs on some other electronics and it worked fine, so I figure it must be something on the DS, or the AC adapter for the DS that was aborting the connection or just failing for some reason. The DS is still definitely in working order though. The DS and the AC adapter are not universal (no built in converter), the AC adapter says it's for 100V/110V, which should work fine with the Canadian voltage converter, usually built for ranges around 120V, though it might be designed to be more sensitive so as to protect the electronics, I don't know. 83.71.33.178 (talk) 11:25, 26 December 2009 (UTC)

Usually, small/cheap converters only convert the voltage and not the frequency - and some devices care about that which is a common cause for problems. Ireland is 220v/50Hz - but Japan is a mess with some places being 110v/50Hz and others 110v/60Hz - which usually means that Japanese-made equipment is tolerant of frequency differences. But it's really hard to know how to solve your problem without more information.

My best advice is to buy an in-car charger for the DS (they are pretty cheap) and charge it up from the 12v outlet on a car. Of course this assumes you have access to a car. The good thing about this approach is that (a) it's definitely going to work - all cars everywhere work at 12volts and (b) you'll be able to use the car charger when you get back to Japan, so the money you spend isn't wasted on a gadget you'll never use again. If you don't have access to a car - you might look to see if there is a USB charger for the DS that would let you charge it from a computer...I guess you have access to a computer because you are reading this reply on one! SteveBaker (talk) 14:17, 26 December 2009 (UTC)

Statements that begin "All cars everywhere..." are usually exaggerations. Austin 10 1932-1933, Wolseley Eight 1946-1948, Volvo PV444/544 1947-1961, Renault Dauphine 1956-1968, DAF 33 1969-1971, and Citroen 2CV 1948-1990 1966 are all cars that are running somewhere on 6-volt batteries. Cuddlyable3 (talk) 21:04, 26 December 2009 (UTC)

This is true - and remember there are still quite a few positive-earth cars on the road, albeit of a similar vintage to those mentioned. A somewhat greater risk these days is finding that the car you want to use as a power source doesn't have a cigar lighter... Tevildo (talk) 21:28, 26 December 2009 (UTC)

Oh good grief. Firstly, it you're going to be pedantic - at least get it right: the 2CV switched over to 12volt batteries in 1966 (I have restored a '68 2CV and I know this for a fact). So perhaps I should have said "all cars less than ~38 years old"...except that the virtual impossibility of buying things like headlamp bulbs and car radios for 6v systems means that a very large proportion of positive ground and 6volt cars that are still on the road after 40 years have been retro-fitted with negative-earth and 12volt batteries. Only the most fanatical car restorer would try to keep such antiques on the road with their original electrical systems. Now ask yourself whether ANY of those 40 year old 6v cars have cigarette lighters with modern connectors - and whether the negative-earth ones are wired such that just about anything you'd plug into it would blow up? (The couple of car nuts who I know who have their Mini's still wired up with negative earth evidently wired up their after-market accessory sockets the 'conventional' way because I know they use them to charge their walkie-talkie's). The answer I gave is very nearly 100% perfect. This kind of pedantry on the RD is getting really tiresome guys. Sheesh! SteveBaker (talk) 04:02, 28 December 2009 (UTC)

Thank you SteveBaker for giving the date when the Citroen 2CV changed from 6 to 12 volt. I have struck and corrected my 1990 date which was for the end of production of the 12volt car. I believe the 6volt runs of the other cars are correct. Parts are available to maintain all these cars and it only takes one diligent maintainer of such a car to invalidate your exaggeration. That's a good question about the availability of cigarette lighters on these 6V cars. Volvo Owners Club write about cigar lighters on Volvo taxis 1950 - 1958. The article Cigar lighter receptacle describes a 6volt version. Philips made a 6volt radio that fits the DAF 33. My understanding is that after the early 70s all mass produced British cars have been delivered with negative earth. In cases where the cigar lighter socket has an insulated surround there seems to be no compelling rule about which polarity its wiring should be. I would expect the center to be +ve and much in-vehicle electronic equipment to survive a reverse 12volt connection, at least if the supply has a 5 amp fuse. The standard for Wikipedia is not being near 100% perfect, it is verifiability.Cuddlyable3 (talk) 02:49, 29 December 2009 (UTC)

Or you could go buy a USB charger and do it that way, as you've obviously got access to a computer! 61.189.63.130 (talk) 00:40, 27 December 2009 (UTC)

(I already said that). SteveBaker (talk) 04:02, 28 December 2009 (UTC)

Steve, there was no need for that comment, it is superfluous for those that noticed you already said it and saying it again is useful for those that did not. You have done the very thing you are complaining about to me in the past, so please don't get touchy about it when it happens to you. SpinningSpark 17:11, 29 December 2009 (UTC)

The behavioral guideline WP:NOOB is helpful here. User 61.189.63.130 may not have posted much before and SteveBaker may take comfort in the adage by Charles Caleb Colton that "Imitation is the sincerest (form) of flattery". I hereby confess Mea culpa that it was my sin that drove SteveBaker to exclaim in piteous cries "Oh good grief...Sheesh!" at 02:49, 29 December 2009. SpinningSpark, he has suffered enough already so please be gentle. Cuddlyable3 (talk) 23:30, 29 December 2009 (UTC)