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New Scientist Answered

I'm sure people are aware but http://www.newscientist.com/
In this weeks issue:
Someone in China has spent some time analysing the US power grid, and figured out that it could be collapsed by taking-out a lightly-loaded sub-network. The US department of homeland security is apparently looking into this. However, Prof Ian Fells (a jolly chap with a beard) of Newcastle University UK says "they only need a bunch of guys with Semtex to blow up the gridlines near a power station"

The Mythbusters are interviewed, but even they don't know why thermite on ice explodes, do you?

And Richard Dawkins has a new book out, from the review:
"Implying that your audience is stupid does not qualify as a great new angle. Yet this is precisely what Dawkins does".
"It's really kind of comical. If "spot the condecensions" is a new drinking game, then bottoms up! There's one in just about every chapter"

L

There's much more, but I mainly wanted to post the Mythbusters link, and the Dawkins review.
(There is an article on Velociraptors)

Discussions

The God Delusion was a powerfully effective self-esteem booster for atheists in the closet.

I am really reticent about reading anything recent from Dawkins after his making quite a mess of The God Delusion, where he uses the very tactics he derides to try and prove his points. He should stick to science, where he has understanding, and leave religion alone.

That's along the lines of the review. L

I'd go with "Peter";

I remembered that back in school my teacher showed us an experiment (and as they say: don't try this at home), what he did was to put a piece of Potassium in a tray of water. At first it caught fire and after a while it exploded. While everyone seemed pleased with the result I couldn't stop thinking why it would blow up. On further investigation it turned out that the Potassium itself does not explode, it reacts violently with the water and greats hydrogen. The process is also exothermic enough that the hydrogen auto ignites and explosion occurs. Which brings me back to the question at hand, how can Thermite on a block of ice cause an explosion? Thermite can reach an extreme temperature of 2500 degrees Celsius (that is about 4500 degrees Fahrenheit), while water will at temperatures of 2300 degrees Celsius (4173 F) split into different new compounds (mostly H, O, OH, H2 and O2). Thus freeing potentially explosive gases in an area of 2500 degrees (hydrogen auto ignites at about 500 degrees C). So there is a possibility that the temperature alone is enough to split free hydrogen atoms which then explodes. This is just a hypothesis but it seems plausible.

Do we even need to invoke thermal decomposition of water? IIRC, aluminium + heat + water = aluminium hydroxide + hydrogen. Thermite consists of aluminium and iron oxide, which heats up during the reaction to aluminium oxide and iron, but presumably there is still some heated unreacted aluminium in the reaction when it hits the ice.

I thought this was the standard reason given for why you have to dump thermite into sand, not water- the hot metals generate hydrogen from the water which then explodes.

Yeah but that is just the reviewer's opinion, my opinion is that I would read anything Richard Dawkins writes because I find him really easy to understand on concepts that normally I find boring as all get out, when he writes about evolution I am able to follow along and don't get put to sleep.

It is an opinon, I thought it an interesting one. The general review was along the lines of "after writing such good stuff before, what is he doing with this?"

L

I haven't read the latest one, but after reading Delusion, and chatting with GH, I've decided that Dawkins is getting old and grumpy.

Instead of using science to explain the glories of evolution (and happening to explain why atheism is a sensible position on the side), he's started using evolution as a blunt instrument to beat theists around their collective noggin.