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Comment Re:Space - application with today's Superconductor (Score 1) 71

Common sense: FAIL

The two sides (in and out) of your can are only at a few hundred Kelvin, and the rate of IR leaving one side for the other is very low (and being only a few Kelvin apart, the net rate is going to be even lower). The sun, however, is at a few million Kelvin, and thus sends out IR at a much higher rate.

Perhaps you're thinking of the inner core where fusion takes place. The surface, which is what radiates heat, light and other things to Earth, is not nearly as hot. One online figure is 5777k:
http://en.wikipedia.org/wiki/Sun

The rest of your point is still valid, radiation isn't nearly as effective at moving heat as are conduction and convection, and that's why a Thermos bottle works.

Comment That's a HUGE instantaneous charge. (Score 1) 348

Okay, so it's ten seconds, not instantaneous, but the power is huge. Another aspect of such high charge rates is the "gas station" needs to be an electrical substation. The standard US house service is 240V, 200A (48KW), which will take about an hour to put a 50KWH charge into the battery, and that's if there's nothing else taking power in the house.

I'll leave the calculation of the power required to put 50KWH into a battery in ten seconds as an exercise for the reader, but it's big. I wouldn't want to be closer than maybe a kilometer if something "goes wrong."

Comment Usenet thread and hobby robot clubs (Score 1) 136

Here's a recent thread on the Usenet newsgroup comp.robotics.misc - the poster asks about how to do a high school club, but (especially with other posts here about how smart kids are) many responses should apply to your situation:

http://groups.google.com/group/comp.robotics.misc/browse_thread/thread/775ceae020f351a6#

I hadn't heard of the TI calculator interface before, and I've been to the monthly Atlanta meeting for years. Lately we've been wowed by one member's 3PI line follower (video on the site below).

And while the following isn't what you asked, it will make a good complement, and you're bound to find others there from your area with school-related activities similar to yours who can help. There may already be a general hobby robot club in your city that welcomes "children of all ages." Google for these:

robot clob
hobby robot

with the name of the nearest major city.

There's certainly a club in Atlanta:
http://botlanta.org/

Be sure to check out the Links page, at the bottom are links to other robot clubs in the USA (there may be other clubs not listed).

Comment Re:Herbal medicine has limited value (Score 1) 713

I saw "treatment" in this article title and was immediately interested for many reasons, but I expected alcohol/drug abuse problems to come up. My main "hobby horse" is that MAINSTREAM alcohol and drug treatment consists of, and is run by, members of 12-step groups (Alcholics Anonymous, Narcotics Anonymous, etc.), which are interently religious (despite the "spiritual, not religious" claim) and have no scientific basis. The influence of "steppism" is so pervasive that it strongly influences addiction research in the USA to the point of looking for genetic causes of addictive behaviors and for other evidence that such behaviors are "diseases" (ideas promoted by the step groups, whose members' PR efforts through front groups such as NCADD and CASA have been so effective that much of the general public believes these things). Any research that involves attempting to REDUCE drinking or drug use, rather than demanding abstinence from its subjects, is verboten and regarded as dangerous!

AC, you're very lucky you didn't get sucked into Al-Anon or ACOA or some such (or maybe you did and you immediately rejected it and/or didn't tell that part of your story). Twelve step groups are the LEAST trustworthy environment I can think of. I was in AA and was a "true believer" for two years (see Box 1980/letters section, April 1990 AA Grapevine magazine for how "grateful" I was), but then I started seeing the cracks in the "perfect" program and started analyzing (going against the slogan "utilize, don't analyze) the step programs, and it took several more years to deprogram myself, verify that these things had NO basis in science or logic, and finally stop going to meetings. Meanwhile I saw too many people commit suicide due to the cognitive dissonance and conflicting messages, with their action always being blamed on "this disease," "he could not be honest with himself" or "he could not see our way of life."

There's much more info about the step group phenomenon and its dangers online at these links:
http://www.morerevealed.com/
http://www.orange-papers.org/
http://www.peele.net/

Just so people know, Alcoholics Anonymous isn't the answer either.

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