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Comment Re:Thank Goodness! (Score 1) 158

A third of the game? I believe it was ten quests and a crappy set of armor. And it isn't DRM, since it isn't required to play. Honestly, anyone who played this game long enough to enjoy the bonus material has earned it. Pick up a used copy, play it to completion, and then tell me that you really needed ten more quests.

Comment Re:5 weeks = long term? (Score 5, Informative) 142

once radioactive material gets inside them it will be there for the rest of their lives.

Wrong. Many radioactive isotopes aren't absorbed by the body and are flushed out rapidly, and some of the most damaging particles (alpha emitters in particular) are at their worst when airborne, only staying 'in' your body for the length of a breath. There are some isotopes that are absorbed easily (namely Iodine), but they are the minority. There is not a single "Radiation", there are a staggering number of different radioactive elements, and for each one, the chemistry matters far more than the half-life.

Comment Re:An optical question... (Score 1) 529

The mixed-color approach works with displays because the light is transmitted directly to the eye (or in the case of projectors, reflected once off a white screen). For ambient lighting, you need a continuum of light because the reflectivity of objects varies wildly by color. If you emit only in three sharp peaks, the reflection from any non-white surface will destroy your white balance. The CRI (Color Rendering Index) of a light source is a measurement of how well it illuminates differently-colored surfaces. A 'white' light with three narrow peaks might look great in an all-white room, but it would fail miserably at rendering anything of color.

Comment Re:It only took a century (Score 1) 348

Yep. The problem with incandescents is that they spread their power along a smooth, predictable curve governed by basic physics. When we put electrical power into a lamp, we want visible light out. But, that visible light occupies a tiny band (about 350-750 nanometers in wavelength) in the possible spectrum. With an incandescent, no matter what you do, you're still dumping ~95% of the radiated power into the infrared ( 350 nm). The best you can do with an incandescent is have it peak in the middle of the spectrum like the sun. But that would require materials that can withstand temperatures above 5000K, and you would only gain a few percent at best. Edison's bulb is a classic example of manufacturability trumping efficiency, and will eventually be regarded as being roughly as useful as a candle.

Comment Hmmm, 1600 km of superconductors... (Score 5, Interesting) 356

" there is a superconducting cable on the ground carrying 200 million amperes, and a superconducting cable in the launch tube carrying 20 million amperes, at an altitude of 20 km there will be a levitating force of about 4 tons per meter of cable length"

That works out to an energy density of (mgh)=1.5e9 J/m. Multiply that by 1600 km, and you get 2.5e15 J, or half a megaton, equivalent to the yield of a small hydrogen bomb. Anyone ever see a superconducting magnet quench?

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