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Everything posted by Gilded
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I'd be amazed if they showed that in a video that's supposed to promote superconductor technology and illustrate its wonderous uses.
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What intrigues me is the possibility that the simulation would be far less complex than the actual reality. If you think about it, what sort of ridiculous amounts of processing power would it take for us to sort of duplicate our perceived reality even locally? It's very unfeasible if not impossible. I think it's extremely likely that if there is a simulation it is far simpler than reality.
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1. The electrons follow the path where there is least resistance. As more and more electrons take one path in a resisting environment the resistance increases and it is easier for some electrons to arc from the main path wherever there might be less resistance (some ionized molecules in the air etc.) 5. The heat is very localized and of course lasts for a very brief while. It's not like everything around you is that hot if you get hit by a lightning. Also, the heat is more extreme in cases where resistivities are much larger than in the human body. Lightning can melt sand into glass but such extreme heat rarely occurs in the immediate vicinity of a human. In many cases some charring is evident, and clothes and hair can catch fire, but I haven't heard of anyone being vaporized by lightning. Also, it is rare to be directly hit by lightning. A direct hit is likely to cause heavy damage but most lightning victims are subjected to just a fraction of the energies involved. (At this point Gilded had a kebab. It was quite tasty.) Btw one thing one should realize is that only some lightning strikes hit the ground. There are potential differences in the atmosphere and some of them are evened out without anything having to reach the ground. 2. Not really. Lightning strikes happen because the potential difference between charges gets large enough to overcome the atmosphere's resistance. This can happen between any sufficiently large opposite charges anywhere, and after the arc the charges are mostly evened out. I wouldn't call it depletion as it's essentially an exchange of charges (although the only particles exchanged are electrons). 3. The paths of ionized air that form before the actual lightning strike aren't too linear. It's just a matter of where the atmosphere is most prone to breaking down, and as most atmospheric processes it can be considered quite random, so it's not just one apparent stepped leader that acts as a "feeler" for the potential difference. 4. The branches rarely hit the ground to the extent that the main bolt(s) does. I'd imagine the returning arc is a simple if extreme case of electric feedback.
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Many songs do. Depending on the artist in question it occasionally approaches dark ambient though. But for example Earth who essentially came up with drone doom have many quite melodic songs with almost blues-like riffs. Drone doom is all about sustained notes, but some have decided that the notes should pass through dozens of distortion and reverb effects. Anyway, seeing how the tempo is quite slow and it can be quite ambient-like I'd guess animals aren't too discomforted by it. Then again it can be quite heavy on the bass so that might be a problem for some animals.
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I remember listening to when my sister's dog was right outside my room. She (the dog) didn't really mind, but looked rather confused.
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Alpha source =/= proton source... A proton source (as in just the production of free protons) doesn't necessarily have anything to with radioactivity as you can just strip the electrons of gaseous hydrogen with relative ease. While alpha particles can increase the proton count of a nuclei I would refrain from calling alpha emitters proton sources. Also, I started wondering whether gold is actually less expensive than Hg-196... While mercury itself is cheap as hell I'd imagine isotope enrichment from the 0.15% natural concentration is quite expensive.
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Well perhaps not the same exact spot but it certainly tends to go back into the ground.
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There's just so much energy in a nova that it will take a very long time to cool down even though it's spreading to every direction. Also, if a gas cloud happens to be near a very massive object (black holes, neutron stars etc.) it will heat up as it falls towards the object. Overall there's a lot of plasma to go around in the universe as gases are heated up by various processes. Even parts of the intergalactic medium are permeated by strands of plasma that can have temperatures of millions of kelvins.
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It saved me a good five seconds when I didn't really have to copypaste the exact same answer to the exact same topic by the exact same person twice. I suppose I could've added that it's counterproductive to make two threads on one topic.
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Iridium being extremely expensive is BS as far as jewelry metals go. Although it's one of the rarest metals it isn't that expensive. $28/g is a price I encountered on eBay. 132$/5g on http://www.elementsales.com. While those are random examples of small individual amounts let's look at current metal market prices. Iridium is at about $14/g. Platinum is at $38/g. Rhodium is at $137/g. I'll agree on the difficulty of machining iridium. Most jewellers can't do it and that is exactly where companies like http://www.americanelements.com step in. The only problem I see here is the possible resizing the ring later if desired. It's going to be essentially impossible. Possible solutions: -Maintain a fairly constant finger circumference -Iridium ring worn on a necklace if it doesn't fit anymore -Get a gold engagement ring AND an iridium ring to go with it. I think the brilliant silvery luster of iridium would compliment gold nicely
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Back when I played WoW with a few friends of mine I recall mentioning how silly it would be to actually make armor and weapons out of real thorium (with the possible exception of a mace or something) and the response was something like "lol nerd". Anyway, I could sure go for some thorium but the website doesn't seem to exist anymore. :| Also, damn Norway and their thorium stockpile that they are unwilling to sell to random people! PS. I wonder if you can craft uranium gear and ammo in WotLK...
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Where did you read that? The only possibly toxic compound I could find is iridium chloride or some other halide, but that's also the case with rhodium yet it's a common jewelry plating material.
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On the topic of mercury the liquid metal isn't really that toxic at all. It absorbs so poorly that for example an accidental breaking of a mercury thermometer in your mouth isn't likely to result in mercury poisoning. Mercury vapor is more toxic but it won't kill fast. Organic mercury compounds are very toxic but they aren't exactly high school lab material (and probably won't kill very fast either). Iodine comes to mind, a few grams is enough to kill and it's commonly found in powder form in chemistry labs.
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I was talking about iridium, not osmium.
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Using the search function is recommended. I think we've had at least two threads on this already. Anyway, here are some suppliers (demonstration kits and industrial grade materials): http://superconductors.org/Play.htm
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Well, fusors aren't too expensive or impractical as far as neutron sources go.
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Definitely. I've heard it wasn't too successful. They must've messed up the schedules pretty bad as customers often complained they had stayed in all day and no one had come. Also, the plumbers complained to Sayo that the mandatory tantric sex service wasn't working out too well as they normally stayed in all day but no one would come.
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Looking at a 5g piece of iridium at the moment I'd say 20g sounds about right. I wouldn't plate it with rhodium though, it has an amazing luster by itself (and I don't think it's any less corrosion resistant than rhodium).
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The guy's expression is pretty intense when he's following the superconductor going back and forth on the magnetic rail. Anyway, I wouldn't say no to some YBCO (I presume that's the superconductor being used). Nifty stuff.
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Gallium is another good example.
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Heh, pretty much what I expected. To illustrate the "density issue" here, a similar volume of sodium would have about thrice the amount of atoms to react with the water.
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No problem. While palladium is a suitable metal it isn't really that "different" if that's a major factor here. It is used in white gold which is a very common jewelry material. As for Ir/Os being too heavy... probably not. They're not that much denser than gold after all. If you want a pure, custom iridium ring you should probably contact American Elements. They haven't been manufacturing them for too long so you'd be among the first.
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This was discussed some time ago in General Discussion as well, perhaps there are some useful ideas here: http://www.scienceforums.net/forum/showthread.php?t=34999 I personally think that iridium is a great choice, but as SkepticLance mentioned you should probably add some sort of personal touch based on common interests or something.
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Is this a trick question? Some definitions: http://www.answers.com/topic/quantum-mechanics http://en.wikipedia.org/wiki/Quantum_mechanics I don't really know if it can get simpler than that. Some key concepts are quantization (discrete units), wavefunctions and uncertainty at sufficiently small scales. I suppose you could call it a branch of physics that describes the mechanics of microscopic systems that can't be accurately described with classical mechanics.