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Scientists/Discoveries
TheEngineer:
--- Quote from: Marlin on Sep 30, 2005, 09:06 ---Happy Birthday E=MC2.
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DURING the summer of 1905, while fulfilling his duties in the patent office in Bern, Switzerland, Albert Einstein was fiddling with a tantalizing outcome of the special theory of relativity he'd published in June. His new insight, at once simple and startling, led him to wonder whether "the Lord might be laughing ... and leading me around by the nose." Joel Holland
An object's mass is its resistance to being accelerated (to having its speed increased). According to E = mc2, an object's mass depends on its energy. This means that the faster an object goes, the harder one must push to increase its speed. (If an object's "rest mass" - called m0 - is the resistance it has to being sped up from a resting position, then Einstein's result can be written more explicitly as E = m0c2/ (1-v2/c2)-½, so m = m0(1-v2/c2)-½, where v2 is the square of the object's speed. As the formula shows, when the object's speed approaches that of light, its mass grows infinitely large, which explains why, regardless of how hard it is pushed, it won't exceed light speed.)
But by September, confident in the result, Einstein wrote a three-page supplement to the June paper, publishing perhaps the most profound afterthought in the history of science. A hundred years ago this month, the final equation of his short article gave the world E = mc².
Full article from NYT's http://www.nytimes.com/2005/09/30/opinion/30greene.html?th&emc=th
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Can you name the (1-v^2/c^2)^-(1/2) term? It has a specific name, and it appears in Einstein's time, length, mass, and energy dilation equations.
Already Gone:
--- Quote from: RDTroja on Sep 01, 2005, 07:50 ---I no longer have the source to back me up, but I found a much higher number than that when doing research years ago (circa 1983). It was closer to 5 Rem/year/pack/day (now there is a division problem for you).
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Roger, I think the 5 Rem/year/pack/day (I know it isn't mathematically correct to express it this way) was the Organ dose to the lungs. I'm thinking that it could come out to a Whole Body Equivalent of 1300mR/year. I don't have the tissue weighting factors at hand, though. Would anyone else like to make the conversion?
sderyke2002:
--- Quote from: TheEngineer on Oct 01, 2005, 04:08 ---Can you name the (1-v^2/c^2)^-(1/2) term? It has a specific name, and it appears in Einstein's time, length, mass, and energy dilation equations.
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It is called the Lorentz Factor generally symbolized by the Greek letter gamma
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