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[Nikov]

I understand that this event is causing people to be angry, frustrated, and wishing they had some means to help. But please, bashing random ignorant people on Facebook is neither a productive or healthy emotional outlet. Kindly return to the subject at hand.

[Ochita]

I have gotten over the initial event, but just... Argg. Humanity..

[Tellemurius]

Please keep the idiocy of those people out of here, we are here to discuss the current situation of the japanese not the dumb hicks that never seen anything else but Fox News.

[Shinziril]

Summary of nuclear reactor shenanigans, to the best of my knowledge:

All of the automatic shutdown systems worked perfectly, stopping the chain reactions in their tracks.  This reduces the heat production to about 10% of what it was (this is from heat produced by various nastily unstable fission products spontaneously decaying).  Remember that these reactors were producing something like 4 GW of electricity, and were probably somewhere around 40% efficient at turning heat into electricity, so 10% of their normal heat production is maybe 800 MW of heat (total for all the plants?).  That's a lot of heat, so you still need to cool the rods, for a while at least (the heat produced by the decay products drops pretty fast as they finish decaying).  The second tricky bit is that you can't cool the rods too fast, or the thermal stresses this produces will shatter the core into thousands of tiny pieces.  They'll still be inside the containment building, but it becomes much more likely that parts of the core will become inaccessible to the coolant and build up enough heat to melt. 

They had (note past tense) backup diesel generators to run the coolant pumps in the case of an emergency.  The tsunami got them.  Saltwater's really not good for engines or electrical equipment.  They DID have secondary backups, specifically batteries, but those only had enough power for a few hours. 

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You can get several situations if a true "meltdown" occurs.  Basically, a meltdown is enough heat building up that the metal rods holding the ceramic fuel pellets actually melt, and possibly the pellets themselves melt.  The first is possible, the second pretty difficult- ceramics are notoriously resistant to heat.

Best-case scenario if this actually happens is the entire reactor core melts and fuses into clump of radioactive magma, which then just sits in the containment building and cools off slowly until we feel like dealing with it.  This would basically destroy the reactor as something capable of producing electricity and be an enormously expensive pain in the ass to clean up, but it shouldn't hurt anyone. 

A worse scenario is the heat generated being enough to melt through the floor, letting radioactive nasties into the water table.  This is obviously bad.  Absolute worst-case scenario is the reactor somehow manages to breach the inner containment building, letting radioactive steam and dust everywhere.  This is the Chernobyl-style situation, but it's pretty damn unlikely from what I've seen. 

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What happened with the one reactor that blew off its outer containment shell was that the cladding on some of the fuel rods melted/exploded off due to thermal stresses in the reactor core, directly exposing the fuel pellets to the coolant.  The problem here is that the pellets contain zirconium, which reacts with water when hot to produce hydrogen and zirconium oxide.  This STILL wouldn't be a problem if it remained inside the reactor, but one of the procedures for emergency cooling is to simply vent off a lot of the steam, which carries away a lot of heat and reduces the pressure inside the reactor core.  Unfortunately, hot hydrogen + outside air = boom.

[Chaoswizkid]

I believe the full comment referred to how the "damn krauts nuked pearl harbor"

*headdesk*

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*twitch*
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*twitch*

I understand that this event is causing people to be angry, frustrated, and wishing they had some means to help. But please, bashing random ignorant people on Facebook is neither a productive or healthy emotional outlet. Kindly return to the subject at hand.

BUT LOOK AT WHAT THEY SAID! It's like they're asking for us to invent some sort of intelligence-based natural selection...

[Il Palazzo]

I believe the full comment referred to how the "damn krauts nuked pearl harbor"

*headdesk*

I'm pretty sure this one is a scathingly sarcastic comment, which somehow managed to pass the sarcasm filter of whomever it was that composed that list.

[Bouchart]

I believe the full comment referred to how the "damn krauts nuked pearl harbor"

*headdesk*

I'm pretty sure this one is a scathingly sarcastic comment, which somehow managed to pass the sarcasm filter of whomever it was that composed that list.

I can't help but think of that line from Animal House:

"Over?  Was it over when the Germans bombed Pearl Harbor?"

[ToonyMan]

When I was a little kid I always thought Pearl Harbor was off the coast of California. 

[Starver]

Note: mid and highschool teachers lie. They don't even bother to tell you "yeah it works, but you won't learn about it until in a few years".

It's "Lies To Children", to take the phrase from Cohen and Stewart.  Explanations that work for that level of understanding.  Once you've understood something, you're then open to finding out what really happens.  And when you've understood that, you can find out what really really happens.  Continue until you know so much about what really really really really really happens that you're one of the few people in the world who are able to make authoritative predictions about what really really really really really really happens, work out a way to experimentally justify that and then try to persuade others nearly at your level to agree that this is a bit better explanation that irons out some of the issues that aren't quite right with their own level of understanding of the subject.

Example:
Electricity.  Flick a switch and motor turns, that's because you let electricity through from the battery.

But you need to have a circuit.  It's like water flowing around the wire, positive to negative (also "current" and "flow" of electricity).  You have to have a circuit, with something like the a fluid going from positive to negative.

Actually, it's not a fluid, and it certainly can't leak from an empty light-socket, it's electrons.  They travel within metals (later, you get to know about non-metals like graphite and semi-conductors).  And they travel from the negative terminal of the battery to the positive.

Look at it closely, however, and the electrons are just jumping around a little, and it's 'holes' travelling around in the other direction that is the 'constituent' of electricity.

...etc. (Covering aspects such as AC, lightning strikes, cooper pairs, superconductivity, quantum tunnelling, the practical details of electron-scanning microscopies, all kinds of other details that I wouldn't deign myself qualified to speak about.  And lot of these would depend upon their relevance as to whether you're specialising in massive amounts of electricity at a time or very small ones, the practical uses of electricity or experimental processes for which electricity is the answer)


All in all, a fairly tame set of lies.  As opposed to the "Lies To Adults", under Ian'n'Jack's equivalent definition of that.

[Starver]

When I was a little kid I always thought Pearl Harbor was off the coast of California. 

It is.   About 2400 miles off the coast.

(Slightly closer than New York is over land, if I did my quick check correctly.)

[ToonyMan]

I'm talking can see from the shore off the coast.

[Greiger]

Don't electrons flow from negative to positive?  Negative charge is an excess of electrons while positive charge is a shortage.  Electrons are of like charge and thus repel eachother while the positive protons on the other end are needing electrons to become "Happy" and attract them? And since electrons are lighter than ions the electrons move instead of the protons?  Of course I learned that from a teacher too..

(Does that mean I'm paying $200 in lab fees alone per course to be lied to?) I'm gunna have to have a talk with Dr. Pivic once spring break is over...

Anyway what's this about a volcano?  I'm not getting anything about it on the local news, and I would think they would be all over that.

P.S. heh I used to think I would be able to see Bermuda and (lol) Cuba from Daytona Beach Florida.

[Duke 2.0]

Anyway what's this about a volcano?  I'm not getting anything about it on the local news, and I would think they would be all over that.

Who cares about volcanoes when we have scary nuclear issues popping up!

[Starver]

Don't electrons flow from negative to positive?  Negative charge is an excess of electrons while positive charge is a shortage.  Electrons are of like charge and thus repel eachother while the positive protons on the other end are needing electrons to become "Happy" and attract them? And since electrons are lighter than ions the electrons move instead of the protons?  Of course I learned that from a teacher too..

If that isn't what I said (I've read it back, to make sure, and it seems to be) then yes, that's one of the stages of learning about electricity.

Until you learn that electrons don't just flow around because they feel like it, or have some magical dwarf-pathing ability to realise that they have a "job" to neutralise the positive charge at the other end, as the next stage is something along the lines of (horribly bastardising it) there actually being an electron 'hole' created by the positive end sucking in the nearest electron, which leave s behind a hole that likely as not sucks in another electron further away from the positive, etc, and that it's the "filling of the holes" which does the work, rather than just the flow of electrons.  Except that this isn't the proper picture, either, but is at considered to be one level up.

(Apart from anything else, it also leads on to explaining semi-conductors better.  I remember my Dad saying to me how in an electronics class he took in his free time he just couldn't work out how a transistor could take a small current and turn it into a larger one.  Until he realised that if he conceptually coloured the electrons flowing into the transistor (or out of, depending on the type) "blue", and the ones trying to flow across the transistor between the power rails as "red", then he could see that pumping a few blues in meant reds would flow.  (Or less.)  And that depriving it of a few blues meant that no reds would flow (or they would now do so).  And, again, it's a little bit more complicated than that, but it's a better picture, and also explains NOT-Gates ("huh? something goes in and nothing comes out, but if nothing goes in, something goes out?"  "Yeah, it's a different set of electrons/lack of electrons as supplied by the appropriate power-rail...").  To the same level of "correctness" as already noted.)


As to volcanoes, not seen anything about them.  Don't know if someone's getting mixed up with the forest fires on the upper hillsides, that I've heard about.  Just checked the latest news, not sure what you're hearing about.  If in this thread, I've definitely missed it.

[freeformschooler]

Anyway what's this about a volcano?  I'm not getting anything about it on the local news, and I would think they would be all over that.

Who cares about volcanoes when we have scary nuclear issues popping up!

To be fair to Duke, a volcano did erupt two days after the quake, but it was not really notable and the worst that happened was that fiery ash got spewed everywhere and some people freaked out and ran away, if I can remember from the article. It was a coincidence probably, as the volcano had previously erupted with much greater force in January. Not as big a deal as the nuclear issue.