Wikipedia:Reference desk/Archives/Science/2012 January 31
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January 31
editRunning and Coughing up Greyish Matter
editSorry, but Wikipedia cannot give medical advice as a matter of policy. |
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The following discussion has been closed. Please do not modify it. |
I have been an intermittent smoker for the last 5 years. Not cigarettes, however--one common "herb" for the entire time, and hookah for the middle 3 of those years. For the two years before I started smoking, I ran regularly, and after running I would often cough up clear phlegm and sometimes get a phlegm feeling in my throat. The coughing up of phlegm was most common when I'd be in a steamy shower afterword. I recently started running again after the 5 years of hookah/herbal smoking. I get the same symptom: in the few hours after running, I'll cough up some phlegm a few times, especially in a steamy shower. However, what is different is that now there are some grayish particles in the phlegm. I assume this is tar/ash/etc. from smoking. Is that correct? If so, is this normal? Is it good to cough up the possibly carcinogenic grayish stuff? If it is good, can I do anything (besides steamy showers) to encourage it to all come out? Thanks, 00:15, 31 January 2012 (UTC) — Preceding unsigned comment added by 138.16.42.247 (talk)
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Bad invention idea ?
editThe Sift and Toss litter box system seems like a bad idea, to me. It's a mesh you place under the kitty litter, then lift to separate the "clumps" from the rest. This will no doubt create a cloud of cat feces dust, which will then be inhaled. So, can this cause toxoplasmosis, or any other disease ? StuRat (talk) 00:58, 31 January 2012 (UTC)
- Seeing as toxoplasmosis is rarely a serious disease, and that if you have a cat at home and regularly clean its litter box then you are likely immune, it would seem that other factors are more important than the probability of toxoplasmosis infection. Whoop whoop pull up Bitching Betty | Averted crashes 01:10, 31 January 2012 (UTC)
- I don't think that assessment jibes at all with our article on the subject. I don't know why you'd assume people were immune. I don't think StuRat's talking about the acute version of it, but the latent version and its potential connection to psychiatric disorders. --Mr.98 (talk) 01:12, 31 January 2012 (UTC)
- Oh, come now. It only seems serious to those unenlightened souls who haven't received their Symbiote yet... ;) Wnt (talk) 02:11, 31 January 2012 (UTC)
- What makes you think this is any worse than using those little scoopers to do the trick? Or the activity created by emptying litter in general? My experience with cat feces, some years old now, is that it does not turn to "dust". You get lots of dust from the litter itself but it seems like the feces itself stays pretty solid. --Mr.98 (talk) 01:10, 31 January 2012 (UTC)
- Depending on how slowly you lift the mesh, airborne dust can probably be minimized. Slow lifting I would think would create less dust due to lesser air currents and a lesser height from which particulate matter "falls" back into the box. Bus stop (talk) 01:16, 31 January 2012 (UTC)
- With any organic pet, as opposed to a plush toy, this is going to be a factor. Not the cheapest thing around, but one very effective approach is a litter box with an automatic rake, which somehow detects when the cat has just been there, and drags a metal "comb" through the litter and dumps the clumps into a collection pan with a lid that opens just long enough to admit the clumps. Obviously, it still has to be cleaned regularly. But much neater than the old slotted-scooper method, and very little dust. ←Baseball Bugs What's up, Doc? carrots→ 02:12, 31 January 2012 (UTC)
- To allay any infection fears you might consider an [link redacted, see below] equipment upgrade. Richard Avery (talk) 08:36, 31 January 2012 (UTC)
- Web of Trust flagged that link, something about malware, viruses, fake goods, and other such goodies. Therefore I have removed it, and recommend against accessing that website. If you feel that this was in error, feel free to undo, but I would still leave some kind of warning message. Falconusp t c 10:10, 31 January 2012 (UTC)
- To allay any infection fears you might consider an [link redacted, see below] equipment upgrade. Richard Avery (talk) 08:36, 31 January 2012 (UTC)
- With any organic pet, as opposed to a plush toy, this is going to be a factor. Not the cheapest thing around, but one very effective approach is a litter box with an automatic rake, which somehow detects when the cat has just been there, and drags a metal "comb" through the litter and dumps the clumps into a collection pan with a lid that opens just long enough to admit the clumps. Obviously, it still has to be cleaned regularly. But much neater than the old slotted-scooper method, and very little dust. ←Baseball Bugs What's up, Doc? carrots→ 02:12, 31 January 2012 (UTC)
- Depending on how slowly you lift the mesh, airborne dust can probably be minimized. Slow lifting I would think would create less dust due to lesser air currents and a lesser height from which particulate matter "falls" back into the box. Bus stop (talk) 01:16, 31 January 2012 (UTC)
Fuschias
editAre fuchsia flowers and berries edible? Thekillerpenguin (talk) 03:52, 31 January 2012 (UTC)
- The Wikipedia article Fuchsia indicates that there are a large number of plants which are classified as fuchsia so it may be quite difficult to make a blanket statement regarding such characteristics. You may have more luck looking for information on specific species. --Jayron32 03:56, 31 January 2012 (UTC)
- Our article says "the fruit is a small (5–25 mm) dark reddish green, deep red, or deep purple, edible berry, containing numerous very small seeds. Many people describe the fruit as having a subtle grape flavor spiced with black pepper." Looie496 (talk) 04:42, 31 January 2012 (UTC)
- But maybe people that discovered that not all fuschias were necessarily edible might possibly not have had the opportunity to describe the taste afterwards... AndyTheGrump (talk) 04:47, 31 January 2012 (UTC)
- Here's a clip that talks about the edibility of fuchsia berries. He says he's eaten them and he still seems alive. I have eaten them on several occasions and my advice from a culinary point of view is 'don't bother'. Googling "eating fuchsia flowers" gives several sites which endorse this practice. Richard Avery (talk) 08:29, 31 January 2012 (UTC)
- But maybe people that discovered that not all fuschias were necessarily edible might possibly not have had the opportunity to describe the taste afterwards... AndyTheGrump (talk) 04:47, 31 January 2012 (UTC)
- Our article says "the fruit is a small (5–25 mm) dark reddish green, deep red, or deep purple, edible berry, containing numerous very small seeds. Many people describe the fruit as having a subtle grape flavor spiced with black pepper." Looie496 (talk) 04:42, 31 January 2012 (UTC)
Why use a mechanical shutter to determine exposure time?
editMechanical shutters fail and have a lifetime-- why not just configure the image-gathering device to collect an image between two set points of time? That's how video DSLRs work, yes? Video DSLRs rely on a "digital shutter" so to speak-- so why not use this for still images? I also worked in a very expensive government lab using very expensive super-high-resolution subdiffraction-limit optical cameras for very expensive microscopes (there were ways of "cheating") ...and I don't remember mechanical shutters being used at all. 199.111.169.54 (talk) 08:55, 31 January 2012 (UTC)
- Maybe (I'm no camera expert) the mechanical shutters were invented before computers capable of doing that were invented? Heck froze over (talk) 09:01, 31 January 2012 (UTC)
- Mechanical shutters are used on most consumer-grade DSLRs (produced today) from 400 dollar ones to 4000 dollar ones. 199.111.169.54 (talk) 09:03, 31 January 2012 (UTC)
- There's various reasons. According to Steve's Digicams an electronic shutter (where the sensor starts and stops capture) requires more complex electronics on the sensor, increasing noise and reducing image quality; a mechanical shutter is cheaper than the additional electronics. On a DSLR or other camera which has removable lenses the mechanical shutter may protect the sensor from dust, etc. Electronic shutters are bad for rolling shutter due to the fact that it takes time to read data from the sensor particularly with cheaper sensors (though you can get this with a mechanical shutter too). Additionally, in a DSLR removing the shutter won't give silent operation because you still have to move the mirror. Mechanical shutter mechanisms have been made for decades and are now reliable and well-understood by manufacturers. Shutter (photography) is the WP article. (Of course there are disadvantages as well, particularly in non-SLR designs.) --Colapeninsula (talk) 10:39, 31 January 2012 (UTC)
- If the image sensor chip is on and exposed to light for a prolonged period, it suffers a temperature increase and becomes more noisy. Using a mechanical shutter may therefore increase image quality. EverGreg (talk) 10:42, 31 January 2012 (UTC)
- This is a known problem with DSLR sensors in video or long exposure mode, and with the recent ability of DSLRs to do video, videographers are routinely warned that DSLR sensors can develop hot pixels which may or may not go away when the camera is cooled down: this is part of the reason why a Canon EOS 5D (meant mostly for still images with a mechanical shutter) costs $2500, but a Canon C300 (a DSLR designed for video use) will set you back $16,000: better cooling and a sensor that is better optimized for video use (i.e., an electronic shutter). Consumer-grade mechanical shutters have a lifetime of about 50,000 exposures, while professional-grade shutters go for 100,000 or 200,000 exposures, by which time you want the camera to be overhauled (or it's obsolescent) anyway. Shutter noises are insignificant compared to mirror noise. Acroterion (talk) 19:56, 31 January 2012 (UTC)
- Also note that, as with electric cars, silent operation isn't necessarily desirable. Having an audio indication that a picture has been snapped can be useful. There's the privacy issue, of people not wanting their pictures taken without their knowledge (like the dreaded "upskirt photos"), but, also, when taking a picture of a model, say, without a flash, it is useful to the model to know when a frame was snapped, so she can then move on to the next pose. StuRat (talk) 20:18, 31 January 2012 (UTC)
- this is true, but almost inaudible shutters were a big selling point long ago, before compact cameras started to add the sound artificially [1] During family gatherings, I've had my wife tell me to stop photographing, because of the incessant noise from the shutter of my modern mirror reflex camera. The noise problem is of course exarcebated by how digital cameras let amateurs like me take as many photographs as we like. :-) EverGreg (talk) 10:07, 1 February 2012 (UTC)
- A lot of photographers who want to be discreet have started using compact cameras like the Leica M9 (a viewfinder camera with a mechanical shutter), or for those without trust funds, Micro Four Thirds system or similar compact cameras with electronic displays and no viewfinder), which do in fact have an electronic shutter, and which make little or no noise (or the shutter beep can be turned off). Acroterion (talk) 15:43, 1 February 2012 (UTC)
- this is true, but almost inaudible shutters were a big selling point long ago, before compact cameras started to add the sound artificially [1] During family gatherings, I've had my wife tell me to stop photographing, because of the incessant noise from the shutter of my modern mirror reflex camera. The noise problem is of course exarcebated by how digital cameras let amateurs like me take as many photographs as we like. :-) EverGreg (talk) 10:07, 1 February 2012 (UTC)
Cycling over hills vs cycling arouund them
editSuppose a cyclist has two routes from A to B, which are at the same elevation. Route 1 goes over a large hill and down the other side, whereas route 2 is flat and goes around the hill. If both routes were the same length, it seems (intuitively) that it's easier to go round, but is this true? I guess that all the energy the cyclist uses in ascending is not restored to the cyclist on descending, so how much further does the route around have to be in order to make it better to go over the hill? I guess that this in turn depends upon the size of the hill... Any thoughts, anybody? Chris (talk) 09:51, 31 January 2012 (UTC)
- Probably not easily resolved on the Science desk as a lot of the decision process is psychology.
- For me the crux of the issue will be the motivation for why one is cycling. In any given circumstance two different cyclists may make different decisions, or even a single cyclist making a different decision when on different bikes.
- My Brompton Bicycle is a very different ride to my road bike, different again to my mountain bike.
- ALR (talk)
- Indeed, it depends a lot on the bike and your level of fitness, as well as the size of the hill and the state (and length) of the roads. No doubt one could come up with a formula taking all those variables into consideration. If you check out a cycling forum I bet someone will have done the math(s). My 1947 roadster (weighing in at around 50lb) doesn't do hills, so it's an easy decision for me. As a general rule I'd say as long as it's a good road surface it usually costs less energy to go around any sizeable hill.--Shantavira|feed me 13:01, 31 January 2012 (UTC)
- When going uphill you expend energy. When going downhill this energy is returned to the cycle/rider system. However you may not be able to take advantage of the returned energy and be forced to burn it off in the brakes. Also the losses in the cycle/rider system are likely to vary with speed.
- As for how much longer the route round would have to be to make it better to go over there are just too many paramerters to give a general answer. Plugwash (talk) 13:17, 31 January 2012 (UTC)
- You're into "effective" use of the energy, and I have a feeling that a flat route would be more effective as power delivery is smoother, not subject to those expending/ recovering transitions.
- Having re-read the question it does seem that it's restricted to energy usage, and in theory there is no difference, although the effects of power consumption are different in each case. Even from a training perspective a hilly route gives a different training effect to a flat route.
- ALR (talk) 13:21, 31 January 2012 (UTC)
- There are a number of ways to approach this problem. If we start with the spherical cow approximation and for simplicity assume no rolling resistance or aerodynamic drag, then it actually takes no energy input to travel the flat path; you could coast indefinitely at constant speed once started. On the other hand, climbing the hill requires an input of energy (more energy and much more instantaneous power if one wants to maintain the same forward speed all the way up, a little bit less if you're content to come nearly to rest as you crest the hill); you must burn calories to buy that gravitational potential energy, even though you'll get that energy back as velocity on the other side. In this simplest scenario, the rider doesn't lose any energy either way – the hill climber's gravitational potential is converted back into speed (kinetic energy) on the way back downhill – but the rider following the flat path wasn't forced to burn any calories in the first place.
- We can start adding bells and whistles to that model, and see where it takes us. Rolling resistance (to a very simple first approximation) can be modelled as a flat energy expenditure per mile of road covered. If route 1 over the mountain is significantly shorter than route 2 around the mountain, then our rider may burn fewer calories on the mountain route just because he isn't leaving quite so much energy on the road (warming up the asphalt and his tires, mostly). If the two routes are the same length over the same type of surface, this consideration is moot.
- Aerodynamic drag puts another wrinkle into it. The power needed to overcome drag goes up as roughly the cube of velocity, so the energy cost per mile goes up with the square of velocity. That velocity-squared relationship means that your high-speed downhill leg puts a big dent in your energy budget, even if you were just crawling on the uphill portion. Once again, a much-longer flat route can offset the drag costs of a high-speed downhill run.
- And finally there are the safety questions. In actual practice, would you want to convert all your hilltop gravitational potential energy into velocity, even if you could? How straight is the road, how good is the surface, and how far is it to the next traffic light? Most of the energy that doesn't get lost to rolling resistance and aerodynamic drag is going to end up warming your brake pads. TenOfAllTrades(talk) 16:32, 31 January 2012 (UTC)
Whichever path requires the least amount of braking. Goodbye Galaxy (talk) 18:12, 31 January 2012 (UTC)
- Some other factors to consider:
- 1) Gearing. If you don't have adequate gearing on your bicycle, you will end up expending far more energy on the hill, as pretty much any bicycle will be geared appropriately for level ground. This is particularly true if you end up walking up the hill, pushing the bicycle as you go.
- 2) Basal metabolic rate. You burn quite a few calories when not doing anything, especially if it's cold and you burn some to keep warm. So, if the level path takes longer, then more calories will be burned this way. However, one could also argue that you should compare the total energy of a 20 minute bike ride on level ground with the 10 minute bike ride over the hill plus 10 minutes resting. StuRat (talk) 20:10, 31 January 2012 (UTC)
- An old cycling rule-of-thumb (supposedly backed by science, though I don't have evidence to hand) is that at anything above 20km/h the greatest resistance to riding comes about through air resistance; obviously this would vary a bit with other factors, such as riding posture, tyre width and inflation, etc. But if we assume your riding speed on the flat is about 20km/h, it's a still day, you're on the same bike, with the same posture, with no use of the brakes, and it's the same distance over or around the hill (to keep things simple) then you're better off going around. The energy is never 'returned' to you on the descent as the faster you go down that hill the greater the wind resistance using up the energy you 'added' riding up the hill; in order to keep your descent speed slow enough not to 'waste' the energy you'd need to use your brakes, which would also be 'wasting' the energy (assuming it's more than just a gentle incline/decline which would allow you to stay around that same 20km/h). We can't say much more in response to the second part of the question without more details regarding how steep the hill is, etc, but the short answer is "significantly". --jjron (talk) 10:44, 1 February 2012 (UTC)
For me, the rule of thumb is that on a good road bike, a thousand feet of climbing equates to somewhat more than 10 miles of flat riding. There are various factors that come into play such as wind and the slope of the climb, but I think that's a decent rule of thumb. Looie496 (talk) 18:26, 1 February 2012 (UTC)
Ice islands
editThis has to do with Fletcher's Ice Island. I'm curious how you find an ice island and how does it move when it would have been in multi-year ice? In May 1952 that close to the pole and in February 1953 near Ellesmere Island there would have been ice cover. Also as a bonus if you look at User talk:Anna Frodesiak#Alfred Ernest Ice Shelf does anyone know if the ARLIS-II and Fletcher's Ice Island are the same thing? CambridgeBayWeather (talk) 10:08, 31 January 2012 (UTC)
- According to our article, Fletcher's Ice Island "drifted throughout the central Arctic Ocean in a clockwise direction". This would be due to ocean currents, with perhaps some impact from the Coriolis effect. The ice would tend to melt a bit in summer and rebuild in winter, possibly becoming landlocked or part of a larger ice sheet at that time. The Arctic may be the only place this is possible, as ice shelves which break off Antarctica quickly drift into warmer waters and melt. The difference is that the Arctic is surrounded mostly by land, which makes "escape" more difficult. StuRat (talk) 19:55, 31 January 2012 (UTC)
- Ah I forgot to link the map. If you look at the first position, May 15, 1952, just west of the pole it is obvious that the island would have been in permanent pack ice. So how can you tell it's separate and how is it going to move? CambridgeBayWeather (talk) 12:25, 1 February 2012 (UTC)
- West of the pole ? :-) I assume you meant left of the pole, in that picture. I don't see why it's obvious that it's part of permanent pack ice, is that just because of how close it is to the pole ? Note that the "permanent" pack ice isn't anchored to land in the summer, so it's free to drift, too, along with anything locked into it. Due to global warming, more of this ice tends to melt off each summer now. We can eventually expect all ice to melt at the North Pole each summer. StuRat (talk) 19:07, 1 February 2012 (UTC)
- Yeah, leftish. That was in 1952 and the permanent ice pack was larger than now. Also even in 2011 we had sea ice in May so it's unlikely that the pole region would have been ice free. CambridgeBayWeather (talk) 02:40, 2 February 2012 (UTC)
frequency limit
editIs there a limit for the frequency(or wavelength) of mechanical (I'm mostly interested in sound) waves in each medium?Also, does anything special happen if the wavelength of a sound wave is equal to the mean free path of the gas molecules(or less) in a gas or when the wavelength is equal(or less) to the distance between the atoms in a solid, or the amplitude of the solid atoms vibrations in thermal motions?--Irrational number (talk) 13:14, 31 January 2012 (UTC)
- Our article on Nonlinear acoustics states that higher frequencies are more attenuated. So yes, there is a limit. This is apparantly an important consideration for ultrasound through biological tissue. Also, because the high-pressure phase of the oscillation travels faster than the throughs, the sinusoidal pattern is distorted. EverGreg (talk) 16:01, 31 January 2012 (UTC)
Big legs through running or jumping
editOkay so many of my mates have quite muscley legs and most of them are in the basketbal team. I have quite skinny legs so because I thought that they gain their muscle mass through all the running they do, I started to work out on a running mill. However now one of my friends said it would probably not be useful for building muscle mass. He said he reckons the most muscle mass he has is due to all the jumping he does. So now I've started jumping on a trampoline. Is that more likely to help build muscle mass or should i be doing a mix of both. — Preceding unsigned comment added by 91.49.33.124 (talk) 14:01, 31 January 2012 (UTC)
- Speaking personally, my thighs were large and muscular when I used to climb 4 flights of stairs 4 times a day at a college! My hubby also tells me that cycling is good for developing muscles. I think it's the resistance that's the important factor. Maybe try incorporating some resistance training into your routine will help. --TammyMoet (talk) 18:29, 31 January 2012 (UTC)
- Any use of your legs will build muscles, although which specific muscles may vary a bit. For overall health, you want low impact aerobic exercise, such as jogging. I'm guessing you are male, but if female be sure to get a sports bra before taking up jogging. An alternative, but without the aerobic component, is walking. This does have the advantage of being more socially acceptable, say, at work. I would walk around the building periodically just to get exercise. While a half hour of walking isn't going to develop muscles as quickly as a half hour of strenuous exercise, you can walk a lot more each day. Park your car far from the entrance instead of close to it, for example, as I do. StuRat (talk) 19:41, 31 January 2012 (UTC)
- Run up lots of hills. HiLo48 (talk) 19:42, 31 January 2012 (UTC)
- My intuition would be that, if you specifically want big legs and want the shortest path to that goal, you need to do weight lifting with your legs. These other suggestions may work too, and may have other benefits, but what really causes muscle hypertrophy tends to be heavy resistance. At least that's my prejudice; I'm no expert and could certainly be wrong. See strength training. --Trovatore (talk) 20:00, 31 January 2012 (UTC)
- Yep, jumping on a trampoline won't give much excercise...99.43.78.36 (talk) 05:48, 1 February 2012 (UTC)
- Oh, a trampoline is great exercise. But it's more cardio than strength. It's strength too, but if strength-as-fast-as-possible is your goal, then there are faster ways than the tramp. --Trovatore (talk) 10:14, 1 February 2012 (UTC)
- Of course I'm talking about a real trampoline. You know, the kind that's at least five feet wide and ten feet long, sprung very tight, so you can do back drops, front drops, flips, etc. Those little mini-tramps, I don't know, I suppose you can get a workout on them if you want to, but it seems boring to me as there's no room to do any real tricks. --Trovatore (talk) 10:21, 1 February 2012 (UTC)
- Oh, a trampoline is great exercise. But it's more cardio than strength. It's strength too, but if strength-as-fast-as-possible is your goal, then there are faster ways than the tramp. --Trovatore (talk) 10:14, 1 February 2012 (UTC)
- Yep, jumping on a trampoline won't give much excercise...99.43.78.36 (talk) 05:48, 1 February 2012 (UTC)
- Don't overlook your genetic potential here. You basketballing friends may well be good at basketball and be on the team significantly due to their genetic predisposition, and specifically due to a high proportion of fast twitch or Type II muscle fibres. These are the fibres that mainly lead to muscle hypertrophy through training, giving your friends their 'muscular' legs. You may have a higher proportion of slow twitch fibres, making your legs skinnier and causing you to struggle to gain much muscle size. The relative percentage of each muscle fibre type is genetically determined and can't be changed through exercise (although the relative sizes can be altered via specific types of training). People with high proportions of fast twitch fibres tend to be stronger and find it relatively easy to gain muscular size; they are predisposed to 'power' sports such as sprinting, jumping, 'weight' based sports, and things that require throwing, kicking, or hitting something hard. And yes, you need to be doing some type of resistance training to have much impact on muscle hypertrophy; jumping may help with this (although the trampoline I expect will be counterproductive), but there are better exercises to do. Sprints will also help a bit, but distance running, such as you would be doing on a treadmill, would have little to no effect. --jjron (talk) 10:20, 1 February 2012 (UTC)
Saltiness of salt
editIs there any way that salt can lose its saltiness, but still be a solid? Would it still be sodium chloride, or what? Edison (talk) 15:52, 31 January 2012 (UTC)
- The saltiness of Sodium chloride(NaCl) is not a property of the molecule. It's more like a property of your tongue. Also see Saltiness. The salt can't be tasted unless the molecule dissolves into free ions, which it does in a polar liquid. If you sprinkle salt in cooking oil, the salt won't dissolve. So as a gimmick, you could say that salt can't be salty without water. EverGreg (talk) 16:11, 31 January 2012 (UTC)
- It could if it weren't pure salt. Before there were effective means of purifying salt, ancients would often mine "salt" which may have had a considerable amount of impurities, including things like insoluble silicates and stuff like that. A supply of salt could, if it got wet, have all of the sodium chloride leach out of it, leaving behind the less soluble (and not salty) components. The resulting pile of leftover stuff would be worthless as an aside, Edison is clearly reading WT:RD and testing the limits of if people will answer the scientific question without bringing up the obvious bible passage. Nice try. --Jayron32 16:38, 31 January 2012 (UTC)
- If that salt loses its salinity in the soil, is it then possible to grow mustard plants? ←Baseball Bugs What's up, Doc? carrots→ —Preceding undated comment added 16:45, 31 January 2012 (UTC).
- Depends whether the mustard seeds were scattered on stony ground or good earth. Tangentially, I've seen it argued that Yesua's recorded parables, if authentic and representative, corroborate that he was raised in a fishing rather than a farming community because his marine and piscatorial allusions generally make sense while his agricultural ones often don't. {The poster formerly known as 87.81.230.195} 90.193.78.57 (talk) 19:36, 31 January 2012 (UTC)
- It is hard to envision people deliberately seasoning meat or other food with "salt" which contained a preponderance of sand, rocks, or dirt. If the salt content of such a product were so slight that its saltiness could be washed or leached out while leaving even half or the original mass behind, I can't envision it being added as a flavoring to food which one planned to eat. Salt with mineral inclusions might have been useful for preserving meat, since salted cured meat (country ham, for instance) is generally boiled or simmered to wash out the salt before eating. Sodium chloride is easily extracted from rock salt or sea water by evaporation and crystallization, and the the salt is typically transported. It does not make sense that someone would transport "salt " consisting mostly of mud, sand, or other minerals when the relatively pure product is so easily extracted. Edison (talk) 17:36, 31 January 2012 (UTC)
- If that salt loses its salinity in the soil, is it then possible to grow mustard plants? ←Baseball Bugs What's up, Doc? carrots→ —Preceding undated comment added 16:45, 31 January 2012 (UTC).
- It could if it weren't pure salt. Before there were effective means of purifying salt, ancients would often mine "salt" which may have had a considerable amount of impurities, including things like insoluble silicates and stuff like that. A supply of salt could, if it got wet, have all of the sodium chloride leach out of it, leaving behind the less soluble (and not salty) components. The resulting pile of leftover stuff would be worthless as an aside, Edison is clearly reading WT:RD and testing the limits of if people will answer the scientific question without bringing up the obvious bible passage. Nice try. --Jayron32 16:38, 31 January 2012 (UTC)
- In Matthew 5:13, Jesus is saying that just as salt prevents meat from going bad so too can Christian people help humanity from going bad, and that if Christians fail to fulfill that mission, that their purpose on Earth was so-to-speak being squandered. That seems to be the significance of the Bible passage reading: "You are the salt of the earth. But if the salt loses its saltiness, how can it be made salty again? It is no longer good for anything, except to be thrown out and trampled underfoot." Bus stop (talk) 17:53, 31 January 2012 (UTC)
- Bus stop is exactly correct here. The whole point, and the entire point of that passage is to note that if a substance with one purpose (salt's purpose is to be salty) loses that purpose, then it has no use anymore. Thus, when Christians lose the property that makes them Christian, they have no use anymore. If Edison has problem understanding this, then the correct article to read is metaphor. Jesus isn't trying to teach his disciples how to preserve meat. He's trying to teach them how to be better people by using the metaphor of meat preservation. --Jayron32 18:08, 31 January 2012 (UTC)
- To answer the OP's question also in bible form but with an historical explanation: No, it would not be sodium chloride. Salt was (is) obtained by evaporating sea water. The 'cheapest' was the whole evaporate. That contained other stuff.
- Did you mean to say sodium chlorite or was that a typo? --Trovatore (talk) 19:43, 31 January 2012 (UTC)
- Don't some people (perhaps from reading the Bible passage brought up above) believe that salt can somehow remain physically whitish crystals, but due to moisture, exposure to sunlight, or simple aging, lose its saltiness, so that it is "unsalty salt? The "saltiness" would be a transient and removable property of the material, like saltines lose their crispness and freshness, or like flowers wither and lose their aroma. This seems to be a popular belief. I've still not seen a good explanation of what substance or compound "unsalty salt" would be. It seems unlikely that someone would transport or purchase a mixture of sodium chloride and some mineral or adulterant. I have seen salt absorb moisture from the air and become moist, but if exposed to heat the brine recrystallizes into salt just as salty as it started. Nor have I found prolonged exposure to sunlight to have any effect on the saltiness of salt. I have done crystal growing experiments with salt, and the 'saltiness" of the crystals formed out of the brine solution did not seem to vary from the first crystals formed to the last. Edison (talk) 22:43, 31 January 2012 (UTC)
- People believe any number of things, believing doesn't make them right. --Jayron32 01:09, 1 February 2012 (UTC)
- Sodium Chloride is sodium chloride. It doesn't change. So this is not about buying adulterated salt. Put yourself into the minds of those living 2000 years ago, that new nothing of modern chemistry. Everything that they shoved out of their salt pans was salt – as far as they where concerned. Lets take the Dead Sea. The salt from there would have a lot of other stuff in it other than sodium chloride -but they still considered it all as just salt. From experience however, they knew it would taste less bitter if they processed it by skimming off the surface crystals. Being a supersaturated brine containing other stuff, it tasted better still if they used this first skim to create a second brine and the next skim tasted better still. The stuff left in the first pan tasted worse that it started off. It still has some salt in it but it tastes as best as I can describe it -a little bit like plaster of Paris. Hardly the stuff you want to add to food. To them back then it was still salt. However, it had lost if savour. The 'goodness' or 'essence' had been removed. So yes, salt in the vernacular sense can loose its saltines in the culinary sense. So if you take out what is good, what is left is of no value and might as well be trampled into the ground – and no weeds will grow there either. Think of it this way. Some people think milk comes from milk cartons but others know it comes from cows. Cow milk, straight from the pail, tastes creamer. That is not because it is 'adulterated' with cream, it is just that the cream has not yet risen to be 'creamed off.' Hence the origin of the term. --Aspro (talk) 19:36, 1 February 2012 (UTC)
- THAT was a bible-teasing question too? I've been had! :-O EverGreg (talk) 10:11, 1 February 2012 (UTC)
Studies on factual beliefs being proven wrong
editI have read in the past and even have a book from the library on the subject right now, but is some good further reading in wikipedia and elsewhere about how the mind works around maintaining a factual belief (flat world, hollow earth, and other disproved ideas) even in the face of overwhelming proof to the opposite. I'm thinking studies or pop science books on how the mind or brain works or the thought processes involved in working out that contradiction. Thanks. I want to be clear on this, though: I'm not interested in religious beliefs, just secular science. Mingmingla (talk) 18:19, 31 January 2012 (UTC)
- Here is another book:How Mumbo-jumbo Conquered the World: A Short History of Modern Delusions --Aspro (talk) 18:35, 31 January 2012 (UTC)
- Oh, and I nearly forgot the classic: Charles Mackay's Extraordinary Popular Delusions and the Madness of Crowds:--Aspro (talk) 18:39, 31 January 2012 (UTC)
- Charles Mackay and Extraordinary Popular Delusions and the Madness of Crowds. The book can be downloaded free. If I recall correctly the chapter "Popular Follies of Great Cities." explains how the theatre is corrupting the youth of the day. CambridgeBayWeather (talk) 12:14, 1 February 2012 (UTC)
- Oh, and I nearly forgot the classic: Charles Mackay's Extraordinary Popular Delusions and the Madness of Crowds:--Aspro (talk) 18:39, 31 January 2012 (UTC)
- If you want a website, Badscience.net is pretty good, they also have a series of books. This is still happening: my son's teachers recently taught (to my kindergartener) the Taste map. I thought we'd long ago learned how much bullshit that was. --Jayron32 18:46, 31 January 2012 (UTC)
- You'll never convince me of that, Aspro! {The poster formerly known as 87.81.230.195} 90.193.78.57 (talk) 19:39, 31 January 2012 (UTC)
- Convince you of what??!--Aspro (talk) 20:01, 31 January 2012 (UTC)
- You'll never convince me of that, Aspro! {The poster formerly known as 87.81.230.195} 90.193.78.57 (talk) 19:39, 31 January 2012 (UTC)
- Cognitive dissonance often leads people to resort to Confirmation bias. I don't even bother trying to reason with Wikipedia editors who are stuck in this mode -as their faith is unshakable. Especially those who post their comments above mine.--Aspro (talk) 18:44, 31 January 2012 (UTC)
- School teachers have actually taught that women have one more rib than men. Anatomists say that men and women both have 12 pairs of ribs (absent surgery or genetic abnormalities). Edison (talk) 22:53, 31 January 2012 (UTC)
- Sure, but that's due to religion, which the OP (for some reason) wants to exclude. If we include incorrect factual beliefs due to religion, the number of such beliefs multiplies dramatically. Start with young-Earth creationism, and proceed from there. --140.180.15.97 (talk) 23:16, 31 January 2012 (UTC)
- You may want to see Pseudoscience and List of topics characterized as pseudoscience. -- Obsidi♠n Soul 03:48, 1 February 2012 (UTC)
- Carl Sagan's The Demon-Haunted World may also be of interest to you. 148.177.1.210 (talk) 16:29, 1 February 2012 (UTC)
- Thanks for the suggestions so far. If you've got more, I'd be happy to hear them, but this is good so far. Mingmingla (talk) 20:16, 1 February 2012 (UTC)
I'm loath to write off superstitions without careful examination. The number of floating ribs can vary from person to person, and I think women's are generally smaller and thinner. I didn't get any solid result on whether women are any more likely to be missing a floating rib than a man. Until I see some hard data I don't regard the notion as disproved, once one acknowledges that the underlying variation prevents it from being consistent in any case. Wnt (talk) 22:16, 1 February 2012 (UTC)
- No. The opposite. Eve was supposed to come from Adam's rib. Hence men are the ones who are said to have a single missing rib. But regardless of the variation in the number of floating ribs, they still occur in pairs.
- Rib is a mistranslation of tzela As you know their where other men around at the time (was not Cain in fear of being killed by other men) The First Adam represents homo-sapien (a mixture of Nominative case/genitive case in the original narrative – the individual(s) is(are) prepubescent). Then there is the discovery of the other sides (side =tzela =male/female). Ie. Adam meets Eve and Eve meets Adam and they recognize their different natures – in other words... A new dawning of mankind which repeats itself every generation. It an analogy not anatomical statement of fact. The worse and most fundamental criticism I have of the modern Christian church is that it not treats its flock as only stupid sheep (and those that had personal contact with sheep will know just what stupid creatures they are) but as mushrooms as well. --Aspro (talk) 16:05, 2 February 2012 (UTC)
- This is why I didn't want religious references. I don't care to hear this as it frequently derails the questions. Mingmingla (talk) 20:21, 2 February 2012 (UTC)
- Rib is a mistranslation of tzela As you know their where other men around at the time (was not Cain in fear of being killed by other men) The First Adam represents homo-sapien (a mixture of Nominative case/genitive case in the original narrative – the individual(s) is(are) prepubescent). Then there is the discovery of the other sides (side =tzela =male/female). Ie. Adam meets Eve and Eve meets Adam and they recognize their different natures – in other words... A new dawning of mankind which repeats itself every generation. It an analogy not anatomical statement of fact. The worse and most fundamental criticism I have of the modern Christian church is that it not treats its flock as only stupid sheep (and those that had personal contact with sheep will know just what stupid creatures they are) but as mushrooms as well. --Aspro (talk) 16:05, 2 February 2012 (UTC)
- Anyway I second 148.177.1.210's suggestion of the The Demon-Haunted World. Though a large part of the book itself is devoted to examining religious superstition.-- Obsidi♠n Soul 08:07, 2 February 2012 (UTC)
I found an entry is the kind of stuff is was thinking of, in addition to the suggestions above. Mingmingla (talk) 03:11, 3 February 2012 (UTC)
- I like this genre you're interested in, so in addition to what's already been named, two I can spot on my shelf right away are Inevitable Illusions: How Mistakes of Reason Rule Our Minds http://www.amazon.com/Inevitable-Illusions-Mistakes-Reason-Minds/dp/047115962X and Why People Believe Weird Things http://www.amazon.com/People-Believe-Weird-Things-Pseudoscience/dp/0805070893/ -- I hope you've already gotten enough to run with, but if not, I'm sure I can find other examples around here somewhere. :-) (Oh, I should probably also mention the writing of skeptics like James Randi and Martin Gardner on various pseudoscientific ideas -- I've read a ton of Gardner, in particular, and think he's at least close to what you want.) Jwrosenzweig (talk) 07:12, 4 February 2012 (UTC)
Unwanted CDs
editTo what use, if any, can they be put?--92.29.198.136 (talk) 20:17, 31 January 2012 (UTC)
- Here is a list of 101 things you can do, some may be more useful than others. --LarryMac | Talk 20:25, 31 January 2012 (UTC)
- Hang one above your bed. If you don't like what you see reflected in it when you wake up – go back to sleep – repeat as often as necessary.--Aspro (talk) 20:32, 31 January 2012 (UTC)
- Ironically, with the right apparatus, it is possible to record sound waves through a recording horn, converge them onto a diaphragm, and use the mechanical energy to cause a stylus to record the sounds by incising excursions into the plastic medium of the disc. With a different stylus, these recordings can be played back through a horn. Edison (talk) 05:57, 1 February 2012 (UTC).
- I love the idea, Edison. Have you patented it? It might actually sell as a retro joke! It would certainly deserve a place in a gallery of modern art! Dbfirs 09:00, 1 February 2012 (UTC)
- Here is one tinkerer's version of how to record music mechanically on unwanted CDs: [2]. Here and here area Youtube videos of it in operation, though this tinkerer uses an electrical cutting head rather than acoustic recording. It sounds pretty good! Here is another tinkerer's version. In the last years of the Soviet Union, rock music fans recorded copies of music on old Xray films in a similar manner, and when they played one could see the "bones" going around. Edison (talk) 17:50, 1 February 2012 (UTC)
- OK, so you can record sound waves then recreate them. But what practical application does it have? Do you think I want to sit at home and listen to someone repeating Mary had a little lamb all night long. Give over.--Aspro (talk) 17:37, 1 February 2012 (UTC)
- If you stick some clear tape over the hole in the middle, they make nice coasters to place a glass on. They can be made into decorative bowls, as well. Edison (talk) 18:05, 1 February 2012 (UTC)
- I love the idea, Edison. Have you patented it? It might actually sell as a retro joke! It would certainly deserve a place in a gallery of modern art! Dbfirs 09:00, 1 February 2012 (UTC)
- Disc-throwing robot. I made one when I was in school. Von Restorff (talk) 06:58, 2 February 2012 (UTC)
Voluntary Eye Divergence
editI have a question that has been bugging me for quite some time. I know that eyes have two distinct motions for focusing - convergence, and divergence. After some training I can point one eye at my nose while the other looks straight ahead, but despite all my efforts I cannot get one eye to look AWAY from the nose while the other looks straight ahead. I have noticed that the eyes never diverge beyond parallel, but after doing research on the muscles of the eye I find no connection from one eye to the other that would "hold" them together to make this impossible. Both eyes can obviously move completely away from the nose with no problem, but they can't both do it at once. The reason I think this is possible is because I've seen people do it (although that was a long time ago, my memory is hazy).
So my questions are simple. What the heck is keeping the eyes from diverging beyond parallel? Is it mental or physical? And is it possible to voluntarily extend this divergence beyond normal? Chris16447 (talk) 20:52, 31 January 2012 (UTC)
- Marty Feldman had some control over his strabismus. Acroterion (talk) 21:24, 31 January 2012 (UTC)
- When I was in high school, I experimented with stereoscopic vision and stereoscopic photography, and through practice acquired the ability to diverge the lines of sight of the two eyes, to be able to combine two different photo images into a 3D view. It became easy to diverge the views of the two eyes and combine two stereo images side by side, or to diverge the two eyes and suppress attention to either eye, voluntarily, when not viewing stereo images. There is not much need for voluntary strabismus outside experiments in visual optics, or other than being a comic actor like the aforementioned Feldman, or his predecessor, Ben Turpin shown here in a Youtube silent movie clip. Not medical advice, but be careful wishing for strabismus, or working to achieve it. I believe that the practice has interfered with the natural and automatic convergence of the eyes, Edison (talk) 22:23, 31 January 2012 (UTC)
- You might find this book chapter interesting. Seems to me like there just hasn't been any evolutionary pressure for humans to instinctively be able to control such things. Nevard (talk) 08:50, 1 February 2012 (UTC)