Wikipedia:Reference desk/Archives/Science/2013 August 2

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August 2[edit]

protect US electrical grid[edit]

How important is it to protect the US electrical grid from electro-magnetic pulses and solar flares? There are people saying that it can be done for a few billion dollars and should be done. Bubba73 You talkin' to me? 01:15, 2 August 2013 (UTC)

See One Second After. I think chances are 50/50 this will get me, and higher I'll get a bureaucrat myself if it do. μηδείς (talk) 02:32, 2 August 2013 (UTC)
 ?? What dialect is your reply in, Medeis, and what does it mean? -- Jack of Oz [pleasantries] 03:55, 2 August 2013 (UTC)
How important to whom? Very important to the US, quite important in Europe, not at all important to certain other countries and regimes. See electromagnetic pulse and solar flare. The usual way to convince the taxpayers is to wait for something to go wrong, and then fix it.--Shantavira|feed me 10:15, 2 August 2013 (UTC)
Important for the US, of course. A friend of mine saw someone on one of the CSPAN channels saying that we need to spend a few billion dollars to protect it. I don't know if he has legitimate concerns of wants to profit from it. Bubba73 You talkin' to me? 17:48, 2 August 2013 (UTC)
The dangers of coronal mass ejection and nuclear EMP and the damage they may cause to the grid infrastructure have been hyped by politicians, by the EMP commission (whose "experts" came from sectors like the missile defense industry, and recommended missile defense systems...) and by EMPact America. The writer of "One Second After" is a friend of Newt Gingrich (and co-author of some of his books), protection against an EMP attack by rogue states like Iran and N. Korea featured in Gingrich's campaign for the Republican nomination; it's the latest threat, after the WMDs of Sadam. The EMP commission has produced a number of reports with claims based on "classified evidence", there's speculation that this has more to do with the quality than the sensitivity of the material. One claim about Iran's secret plans turned out to come from an Iranian magazine that was in fact quoting a story from the NY Times or Washington Post. There's the claim of a Soviet super-EMP technique that was supposedly given to the Iranian and North Koreans (we've heard super-weapon claims before, like red mercury ).
The main points of those claimed dangers are:
  • EMP would destroy all electronics that control the grid.
  • Big transformers would be destroyed by EMP or by strong solar events, and replacing them will take years.
  • Nuclear installations would go in meltdown because their controls aren't EMP-safe.
  • without power, the US would fall back to the stone age and up to 90% of the population could die the first year.
In fact, safety of nuclear installations has been reviewed several times in the last decades, addressing those specific points. The grid is protected by circuit breakers and fuses: it will go down when such an event occurs, not because of damage, but because that's the only way to protect it, solar mass ejections and EMP can induce large currents in long conductors (not only electric cables but also in pipelines), cutting the circuit is the only option. There has been one documented case of a power station that burned down after a nuclear test, in the Soviet Union.
Claims that three nuclear bombs were enough to cover the whole country didn't take into account that the ionization of the outer atmosphere created by the first explosion would make it impossible to create a second EMP for days or weeks. For that reason a classic atom bomb is better than a hydrogen bomb, the tiny delay between the first and second stage is sufficient to prevent the second one having any effect.
There's a lot of nonsense being told, I've seen a video from a "prepper" (who supposedly prepare for such events) saying that without electricity there was no way to get at the gasoline from the tanks at gas stations; seems he doesn't know that during inspections these tanks are sampled with a beaker on a stick. Ssscienccce (talk) 13:01, 4 August 2013 (UTC)
Thank you, that was very informative. Bubba73 You talkin' to me? 16:41, 4 August 2013 (UTC)
Ssscienccce, what happens if the 3 bombs are detonated simultaneously? --220 of Borg 10:43, 7 August 2013 (UTC)

As it wasn't mentioned here I'll just toss in that last years' (in the USA) Revolution (TV series) covers a related scenario, what happens if the electricity stops? Apparently the cause is not specified. (or is that where this query originates?) --220 of Borg 10:43, 7 August 2013 (UTC)


Why so so many people online fight about whether Edison was cleverer / more significant than Tesla? (talk) 11:49, 2 August 2013 (UTC)

People love to argue about all sorts of things - Android versus Apple, Mac versus PC, dogs versus cats, classic StarTrek versus STTNG (versus Voyager (versus Star Wars)), Ferrari versus name it and there is a vigorous online debate about it. Edison and Tesla were rivals during their lives - they both did a bunch of crazy stuff, so it's easy to take sides. Tesla is a particularly good topic to rant about because he claimed to have done so many amazing things. We're 100% sure he didn't actually do all of the things he claimed - and 100% sure that he did do some of them. So there are large grey areas in his achievements that are great fodder for online flame-wars. Edison is also a great target because he had a great propensity for taking things invented by his employees and claiming that he, personally, invented again - he's a great target for debate. SteveBaker (talk) 14:29, 2 August 2013 (UTC)
Of course the Star Trek/Star Wars arguments are kind of silly, given that Babylon 5 is so much better than either one. --Trovatore (talk) 02:41, 3 August 2013 (UTC)
Did you see Pawn Stars last night? Edison and Tesla started the argument. Bubba73 You talkin' to me? 21:34, 2 August 2013 (UTC)
Tesla was more of a "pure" scientist, and wasn't all that good at public relations (it can't be a coincidence that the typical "mad scientist" kinda looked like Tesla). Edison was more of a "practical" scientist, and was much better at P.R. AC won out over DC, but we don't call the power company "Commonwealth Tesla". Tesla teamed with George Westinghouse to get into the practical side, but Westinghouse is the name we remember. Tesla sued Marconi over the invention of radio, and eventually won the suit, but we associated radio with Marconi nonetheless. ←Baseball Bugs What's up, Doc? carrots→ 22:57, 2 August 2013 (UTC)
They both did great things in their youth, and then made completely untrue claims in their old age. By picking and choosing which part of their life you look at, or how much of their claims you believe you can make it look like either was "Better".
On top of that "Invention" rarely happens like it does in the movies. People incrementally improve existing ideas. To say that any single thing was wholly invented by any single person is misleading. So that gives you the perfect "ammunition" to discredit inventors you don't like by pointing out the earlier work that they built upon. (While ignoring the fact that your favorite inventor did the same thing!)
However, I think a lot of the current drama over the two inventors can be traced back to this very misleading infographic/comic from The Oatmeal.
APL (talk) 02:38, 3 August 2013 (UTC)
Mick West who runs the site metabunk even thought it necessary to "debunk" Tesla's importance, as just another topic next to governement conspiracies like chemtrails, water fluoridation, killer vaccines and 9/11 inside job claims: Ssscienccce (talk) 14:46, 3 August 2013 (UTC)


Why do dogs put their heads out the car window? (talk) 11:58, 2 August 2013 (UTC)

I don't think we know for sure - but it's clear that the wind in their faces is enjoyable. I kinda suspect that they also like that smells are zipping past with incredible rapidity so they get the same experience of speed that humans get from looking out of the window. SteveBaker (talk) 14:22, 2 August 2013 (UTC)
This source corroborates Steve's version. It's not a scientific publication, but some kind of dog behaviorist. According to it, apparently, dogs do not enjoy being blown on the face, and it's even detrimental to them. But since their sense of smell is complex and advanced, they are exposed to a plethora of sensations. OsmanRF34 (talk) 22:29, 2 August 2013 (UTC)
Dogs definitely do not like wind in their face. When I have washed my dogs, I have dried them off with a hairdryer. It takes a few goes before they are not distressed by it, but after a while they clearly enjoy the sensation of warm air on their bodies, but never cold air and never on their faces, hot or cold. However, it is part of a dog's nature that they feel obligated to track the location of every living thing in the vicinity, and (depending on breed), bark at it at least once. That's what causes dogs to stick their heads out of car windows - so that their barks have a chance of being heard by all those things going past. Note that dogs determine whether or not something is alive is a simple rule: if it a) moves about in its entirety, and b) makes a noise, then it may be alive and needs to be barked at. Thus for a dog, a car going past may need to be barked at, even if no humans are clearly visible in it. Many owners of two dogs of the more intelligent breeds will have noticed that when both of them are in the car, only one puts his head out and barks - generally not the lead (alpha) dog. That's because with one dog doing the chores (barking at things and keeping track of them, the other dog can take a rest - delegation. (talk) 13:08, 6 August 2013 (UTC)

Heat screen[edit]

Can you have a sort of heat cream that blocks heat in the same way that sun screen blocks UV? — Preceding unsigned comment added by (talk) 12:16, 2 August 2013 (UTC)

Heat arrives by several mechanisms - conduction from the air in the environment and IR radiation from other hot objects (such as the sun) being the most obvious. You could perhaps design some kind of cream that reflects IR light away from you - but you'd still get hot from conduction from the atmosphere. You could certainly make something that evaporates like natural sweat to cool the body for a while - but it would dry out fairly quickly - so you'd need to re-apply it. In a sense, we already have this substance...just wipe your skin with a cloth soaked in plain old water - and you'll feel obviously this is possible. SteveBaker (talk) 14:20, 2 August 2013 (UTC)
I remember seeing a stuntman that had invented a paste that you could put on your skin when doing fire stunts. He could set his hand on fire and let it burn for 30 seconds without feeling the heat. (talk) 09:11, 5 August 2013 (UTC)

Could more co2 be good for the planet?[edit]

Without questioning global warming or that it's man-made, could we discuss whether it's a good thing? Who said that present or past levels of co2 are better than future higher levels? Who said that present or past temperature is better than a future higher level? — Preceding unsigned comment added by (talk) 12:21, 2 August 2013 (UTC)

Well, it all depends on what you mean by "good" and "better". How do you measure "good" ? Good for who ? Our article on the economic impacts of climate change contains some possible answers. Broadly speaking, there is agreement that global warming will have economic costs, but there is disagreement over whether these costs could be catastrophic; whether they could be significant but manageable; or even whether they could be marginal compared to the long-term benefits of global industrialisation. Of course, if you are living on a small flat island a few metres above sea level, this debate must all seem very academic. Gandalf61 (talk) 12:49, 2 August 2013 (UTC)

Ok, good for nature, in the sense there's more of it. Or even agriculture, in the sense that we can produce more, maybe because there's more rain or a bigger area where we can plant. I suppose that many human communities will have to be re-located, which is not a big drama as such, since humans have always migrated. — Preceding unsigned comment added by (talk) 12:54, 2 August 2013 (UTC)

There is lots of detail about agriculttural impacts in our artcile on climate change and agriculture. Headlines are a low to moderate degree of global warming is likely to increase food production in some parts of Asia and North America, but decrease it in the rest of the world. Gandalf61 (talk) 13:08, 2 August 2013 (UTC)
For more specific research, you may be interested in reading about SoyFACE [1]. Their research has identified many problems with growing crops in the midwest USA under higher CO_2 levels. One I found interesting: soy plants do grow a little faster, but their CN ratio also changes, and they end up getting more beetle damage. So the net result is still a negative impact on crop yields. SemanticMantis (talk) 13:10, 2 August 2013 (UTC)
Definitely NOT good for nature. Increased temperatures force plants and animals to migrate towards the poles - but the timescales of this change are too short for plants to spread very far - and much too fast for animals to evolve. I was listening to a report just a few days ago that trees that are normally resistant to forest fires in the south-western part of the USA are becoming less resistant because of climate change - and the overall increase in temperatures makes forest fires much more likely. The consequence of that will be the eradication of large forests in those regions. The trees don't have time to re-seed themselves further and further north because it takes 30 years to grow a tree - and each one can only travel a dozen feet from it's parent. At that rate of movement, these plants can't possibly outrun the effects of climate change - and face extinction.
This isn't good for humans either. If nature suffers - so will we. It's possible that human activity such as farming can move further away from the equator - but because our society has strict national boundaries - this will be disasterous for some countries and a win for others. The stresses that causes will result in international tensions - wars and other very bad things.
The idea that crops will do better because of increased CO2 levels is true for some species - but it's also true for some invasive species, native weeds and many diseases of plants - so it might be that our farmlands become overwhelmed by disease and non-productive species.
Truly, the result of this will be a massive loss of bio-diversity - and that cannot be good for mankind or "nature".
SteveBaker (talk) 14:14, 2 August 2013 (UTC)
In the long run the Earth can survive a lot, and what is "good" is quite mysterious. But in the short term any change is bad change. For example, if you lived on the Grand Banks 8000 years ago, the rising sea level would be a big problem. Return of the ice age would be a big problem. As in that example, sometimes there is actually no way for climate not to change (either sea level must rise or the ice age must return) but it still sucks! In our case though, we're shooting extra holes in the bottom of the boat. Wnt (talk) 14:57, 2 August 2013 (UTC)
It doesn't make sense to ask what's "good for" the earth. It only makes sense to ask what's "good" for us, or for some category of life. If the asteroid hadn't hit the earth, maybe the dinosaurs would have continued to flourish a lot longer, and would have eaten up all of our biological ancestors. So that event was bad for the dinosaurs, good for us, and neither good nor bad for the earth, as the earth is just an object. ←Baseball Bugs What's up, Doc? carrots→ 16:26, 2 August 2013 (UTC)
Yes, if you do not count life forms as a part of the planet - that's true. Even life itself will probably continue flourish despite what mankind is doing here...but you might end up with oceans containing nothing but algae and jellyfish and land containing nothing but fire-ants and cacti. In time (just as after the other mass-extinction events) new species will evolve and the world will carry on - albeit in a different direction. Individual humans may not see a significant degradation in quality of life during their lifetimes - but each generation may have slightly harder lives than the previous. So any consideration of "better" and "worse" has to be made relative to what we, as humans and as a species, consider good and bad for the future survival of our genetic heritage. SteveBaker (talk) 17:27, 2 August 2013 (UTC)
In the very long term, isn't the occasional mass die-off a driving factor of evolution? With more complicated and "Advanced" species emerging after the die-off?
Not that I'd personally want to be one of the ones who die off, but if I were an immortal god, it might be interesting to roll the dice and see if something better than humanity crops up in the million years after an ecological disaster. APL (talk) 02:26, 3 August 2013 (UTC)
Evolution doesn't select traits that are "advanced" or "complicated", though. It's not a progression of "better" life forms so much as "life forms that survive/pass genes best in this environment". The other problem is that evolution doesn't plan: given two mutations: mutation A that makes the animal a little smarter and mutation B that makes it no smarter, but more agile. If A and B are mutually exclusive and B is better right now, B is going to win; even if a thousand years down the road, A would have been the better option.Phoenixia1177 (talk) 08:25, 3 August 2013 (UTC)
Whenever these discussions come up I'm reminded of this comic by Humon. (Note: much of the artists other work is NSFW.) It points at the difference between "good for the planet" and "good for us humans". Sjö (talk) 08:30, 3 August 2013 (UTC)
Phoenixia, I understand that, everyone knows that, but historically, haven't more complex (And therefore more "Advanced" so far as I'm concerned) life usually emerged from such global catastrophes?
(Specifically because, as in your example, after a mass die-off, there would be little competition for resources, so A and B are not immediately in direct competition, allowing a brief period of exaggerated biodiversity.)
I'm certain I've read that in a number of different sources, but I can't quite seem to find an article on WP that describes this idea, perhaps just because I don't know what it's called. APL (talk) 09:13, 3 August 2013 (UTC)
I don't think "everyone knows that", I think it get's pointed out a lot, and I think that's because it's a very common error that people make. You may not have meant that, but what you wrote can be read that way. As far as I've read, mass extinctions are important because, generally, what survives isn't strongly correlated with ability to survive prior to extinction event; so it hits across the spectrum of success. An effect of this is that with the dominant species removed, other species can diversify and, possibly, break current trends (not always the case). But I don't see any reason this would imply an increase in complexity/intelligence, just an increase in change as different groups take over dominant positions (and I'm not sure everyone even agrees that this is an extremely drastic effect.) Some things you may want to read: Extinction event under the evolution section, and [2], [3], [4], [5], [6], [7].Phoenixia1177 (talk) 10:03, 3 August 2013 (UTC)
  • The climate change problem arises not so much because more CO2 would be bad per se, as because of the extremely rapid rate of change. Ecosystems in many places just can't adapt fast enough to keep up with the rate of warming. If we had been living in a world of 500 ppm CO2 for millions of years, our geographic distribution would be adapted to it, and we would not see it as a problem. Looie496 (talk) 17:32, 2 August 2013 (UTC)
The sheer number of humans on the planet is currently causing a major extinction event anyhow. Pumping huge amounts of carbon dioxide into the air and making life even more difficult for anything else is just one amongst loads of other things we're doing. We've parks to conserve some species we've taken a fancy to, they will die because they can't move. Dmcq (talk) 19:41, 2 August 2013 (UTC)
Hominids have been extinguishing species and altering the environment from the time they learned to hunt, build fires, grow crops, etc. ←Baseball Bugs What's up, Doc? carrots→ 22:54, 2 August 2013 (UTC)
It sounds to me like you don't see the difference between some people wearing a path across a field with their feet and tarmacing the whole field over and using it as a car park. Dmcq (talk) 08:09, 3 August 2013 (UTC)
Have you tried parking downtown? Sheesh! What's a few little bugs? Someguy1221 (talk) 08:31, 3 August 2013 (UTC)
I'll concede that we did, in fact, pave paradise to put up a parking lot. ←Baseball Bugs What's up, Doc? carrots→ 09:01, 3 August 2013 (UTC)
I'm looking forward to going to the tree museum though - and $1.50 for entry sounds pretty cheap. SteveBaker (talk) 14:26, 3 August 2013 (UTC)
I've just looked that up and seemingly it was referring to Foster Botanical Garden in Honalulu and the entrance fee is now $5, still good value. Dmcq (talk) 17:39, 3 August 2013 (UTC)

Klaatu is on his way to fix the problem. Count Iblis (talk) 16:09, 3 August 2013 (UTC)

Medicine package US and Europe[edit]

Why? In the US they seem to prefer a plastic jar, and in Europe they seem to prefer all pills packed individually. — Preceding unsigned comment added by (talk) 13:11, 2 August 2013 (UTC)

Over here in the UK it seems to depend on the individual pharmacy. For example, I noticed at the old-fashioned chemist I went to last week the drugs were dispensed in a bottle, whereas when I go to Boots or a supermarket pharmacy I get the drugs in a blister pack. --TammyMoet (talk) 10:29, 3 August 2013 (UTC)
Our articles Packaging and labeling and Blister pack has some general information, and a little on packaging for pharmaceuticals, but nothing that explains the different preferences in the US and Europe. Sjö (talk) 20:39, 3 August 2013 (UTC)
There's a difference in how pharmacists work in the US and in Europe (chemists), which may play a role. In the US, they often open up bottles from the manufacturer and place them in new bottles, to change the quantity, label, etc. Blister packs don't lend themselves to this. In much of Europe this process is discouraged, since it introduces possibilities for errors, theft, adulteration, etc. So, blister packs work better there. StuRat (talk) 22:24, 3 August 2013 (UTC)


is it necessary to pressurize gas before burining.? give any referencve... — Preceding unsigned comment added by (talk) 14:20, 2 August 2013 (UTC)

No, as pranksters with their acetoxy balloons can attest. But I wonder what the lowest possible pressure for a "rapid burning" reaction in a room temperature gas would be (I fear creativity about the definition of burning might obscure the answer) Wnt (talk) 14:53, 2 August 2013 (UTC)
No, but its way more effective to handle and transport that way. --Kharon (talk) 15:37, 2 August 2013 (UTC)
Not at all. The hydrogen pop test relies on the flammability of freshly prepared hydrogen gas at room temperature and pressure. Fuel-air explosives burn gases like ethylene oxide at atmospheric pressure with devestating effect. (talk) 03:34, 3 August 2013 (UTC)
Combustible gas can also burn in a partial vacuum, so long as there is an oxidiser present, that being oxygen or not. Plasmic Physics (talk) 01:50, 5 August 2013 (UTC)

Vitamin overdose[edit]

Can you die from a vitamin overdose? How many multivitamins or vitamin E or vitamin b6 tablets would you need? Pubserv (talk) 18:07, 2 August 2013 (UTC)

Yes - see Hypervitaminosis A (and Vitamin poisoning, though that doesn't mention any fatalities). AndrewWTaylor (talk) 18:10, 2 August 2013 (UTC)
How many multivitamins or vitamin E or vitamin b6 tablets would you need? Pubserv (talk) 19:35, 2 August 2013 (UTC)
For vitamin A, Hypervitaminosis A#Pathophysiology says that 21,600 IU per day over an extended period can cause problems, while a portion of a polar bear liver can kill you in a single dose. Hypervitaminosis E gives a safe limit of 1500 IU per day. The B vitamins are water-soluble, so they don't build up over time the way the fat-soluble vitamins do; B vitamins gives an upper intake limit of 100mg of B6. --Carnildo (talk) 01:12, 3 August 2013 (UTC)
Xavier Mertz may have died of vitamin A poisoning - see the article on Douglas Mawson --TrogWoolley (talk) 18:18, 2 August 2013 (UTC)

Soluble medication pills.[edit]

When they dissolve in the mouth, do they begin to enter the body/bloodstream in the mouth, or does it happen afterwards/only in the stomach? Pubserv (talk) 19:32, 2 August 2013 (UTC)

This will vary with the type of medication. Some are absorbed quickly through the mouth (see Sublingual administration), whilst others are absorbed much more slowly through the stomach. Dbfirs 19:48, 2 August 2013 (UTC)
What if it's Zyprexa? Can general medicines (soluble medicines) be absorbed if it is ON the tongue? Pubserv (talk) 09:13, 3 August 2013 (UTC)
The active component of Zyprexa is almost insoluble in water. Maybe some people smash the pills and mix with water, but unless it was prescribed to be taken like that, no one should do. OsmanRF34 (talk) 22:37, 2 August 2013 (UTC)

Medicine without side effects.[edit]

Why can't we make medicine/drugs WITHOUT side effects? Pubserv (talk) 19:34, 2 August 2013 (UTC)

Because a side effect is just an effect we don't want, and we want our medication to be effective. If a medication doesn't have an effect, it's not a medication, it's inert. And if it has an effect (which it does by definition), there will be circumstances in which that effect is undesired, or a side effect. Most substances have multiple effects, of course, which, along with the problem of different substances affecting different people in different ways under different circumstances, provides a fuller answer to you question. - Nunh-huh 20:05, 2 August 2013 (UTC)
I find the legs on tables annoying. They get in the way. Why can't you design a table without any legs? Now there's a nice straightforward problem, it can't be anywhere near as hard as making drugs without side effects. Dmcq (talk) 20:14, 2 August 2013 (UTC)
"Medicines" without side effects already exist. Most homeopathic preparations fit that bill. Problem is they don't have any desirable effects, either. Dominus Vobisdu (talk) 20:21, 2 August 2013 (UTC)
They do have one effect: As a diuretic on your bank account. ←Baseball Bugs What's up, Doc? carrots→ 22:50, 2 August 2013 (UTC)
You can hang a table. Not sure if it technically stops being a "table", but you can still put chairs around it and eat. Might have to worry about your elbows banging chains instead of knees banging legs, but it solves the underlying problem. Drugs, yeah, much harder. No clue. InedibleHulk (talk) 06:18, August 3, 2013 (UTC)
Isn't that just like what happens with the medicines?, get off the ones that make you feel ill and you get ones that make you fat. Dmcq (talk) 08:19, 3 August 2013 (UTC)
Even oxygen has side-effect (that is, undesirable effects). It comes down to the fact that we are complex systems. But nature chose to re-use the same components in different body parts. You'll find the same protein, neurotransmitter, hormone in different parts, fulfilling a different function.
Aspirins, for example, prevents blood clots because they inhibit a certain group of enzymes in platelets. However, these same enzymes are also in the stomach lining and serve to protect it against acids. Aspirin cannot distinguish between them and so while it prevents clots, it also destructs the protection of the stomach lining leading to ulceration.
On a bright side, science strives to develop more target drugs.
For example II: histamine. It regulates sleep and wakefulness, but also your autoimmune system. An antihistamines would affect both processes, however, chemists were able to discover new antihistamines that bind to one specific histamine receptors, the one that regulate allergic responses. These antihistamines are present in allergy medicines that won't make you drowsy.OsmanRF34 (talk) 22:55, 2 August 2013 (UTC)
It was related but not the same. Pubserv (talk) 08:27, 4 August 2013 (UTC)