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Recent content by philguy

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    Grand Central Time Freeze

    alright, that is pretty cool! Man, respect to those guys! "I can't move my car, there's people frozen everywhere!" - "ah, never mind"
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    GB LaserGlow...  CLOSED!

    Re: Possible GB Green, Blue, Red and Yellow lasers 12 % off which prices? LG? also, would you also sell greenies?
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    My flashlight is cutting electrical tape w/o lens

    Re: My flashlight is cutting electrical tape w/o l No, I didn't tell you that...
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    mw to temperature

    even assuming 100% absorption, there is heat flow and mass to be considered. But if you just say "I have a totally black iron cube, 1cm³, and I shoot at it with 500mW for 10sec", then temperature rises 1.4K (or °C). So if you could give us some more specific information, we might be able to...
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    My flashlight is cutting electrical tape w/o lens

    Re: My flashlight is cutting electrical tape w/o l Fun stuff: Find an overhead projector that can fold away the arm with the lens. If you then turn it on, you get a 250W-spot focused to about a square cm. darkish paper will start to burn in there. If you take regular paper with black letters on...
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    Acela Express Train Horn

    Are you freakin kidding me?!? That is insanely cool! Through the youtube clips, I found my way to shiphorns.com. Go down to "media", and check out those abhorrently cool videos! Btw. their sound is way better than the youtube video sound. Now, my headphones are not jacked into my pc directly...
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    2mW yellow visability vs 5mW blue at night

    Erm, really? I always thought shorter wavelengths (blue) are reflected stronger, as the daytime sky is blue (lot of scattering) whereas the red part hits the ground barely scattered, and at sunset, all the blue light has to pass through a great deal more of atmosphere, getting scattered along...
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    1 watt handheld IR laser

    afaik coke is transparent to IR. You can check for yourself: get a cheap camera w/o IR filter and an IR diode (remote works, stronger is better) and check all the objects for transparency. If you can still se the IR dot on the screen if the object is between them, it's transparent.
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    nice little circuit simulator

    You betcha it is useful! I used this over the course of the last year whenever an idea sprung to my mind. It's imple and easy, and when I just want to see what happens when I "hook that to that", I don't care which transistor it is! This is a perfect little applet, including loads of sample...
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    Faster than the speed of light?

    Although why it is exactly c, or why c is at that place, or why in the world it is e = mc squared and not cubed or linear, no one knows. I would say, that goes off into metaphysics. Well, light does have an impulse, and does apply a force when it hits something. You can calculate that the...
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    Faster than the speed of light?

    Yes, there is no rest mass. But yu can say that energy has mass, too (so a full battery would actually be heavier than an empty one), so you can say a photon has mass. Better speak of a photon's imulse, though (although that is NOT a photon's mass). Just saw this. So the 100tons figure is just...
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    Faster than the speed of light?

    The way I understood the slower speeds of light was that within substances, a photon flies with the original c, but hits an atom, gets absorbed, and some time later (fs? ns?) reemitted. That little time delay is what causes photons to "appear" slower, although the lower speeds in matter are just...
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    Question about the sun and magnifying glasses

    Hello, I am a link! <- think you're looking for that. Also, don't count for more than 700W/m² - that will make your calculations a bit more realistic. You'd get a 1000W light source - but not a 1000W laser. The light you get will be continuous spectrum, incoherent and far from having been...
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    Gamma Ray laser breakthrough?

    So far, I'd say don't worry. Let them first become successful at mounting a "visible" laser capable of destruction onto an airplane, before you start talking about mounting a hypothetical laser consuming huge amounts of powers on a possibly unmanned plane. Also, I don't think the advantages of...
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    Faster than the speed of light?

    Well, try going as fast as c before you plan on going beyond that. Because even approaching c is a pain in the rear. Deal is, the faster you get, the higher your mass. Or in other words, around c your body weight is no longer 150 pounds, but all of a sudden 100 tons! And try to accelerate...




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