WTHDIJS Video of the Day

Discussion in 'HardForum Tech News' started by HardOCP News, Aug 30, 2016.

  1. HardOCP News

    HardOCP News [H] News

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    If this video does not qualify as the "what the hell did I just see" video of the day, I don't know what will. Although it is kind of hard to see at times, the laser is actually moving the tinfoil in the vacuum chamber.
     
  2. travisty

    travisty Gawd

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    Not sure how this is a wthdijs video... it's well known photons have a force. See Plank back in 1900.

    An application of this is beam-powered propulsion with solar sails being the most well known.

    Solar sail - Wikipedia, the free encyclopedia
     
  3. Tiberian

    Tiberian DILLIGAFuck

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    What I noted was the tin foil moved as HE moved himself. It's obvious from the earlier parts in the video there's some vibration happening and he's causing it himself from either contact with whatever apparatus he's constructed to do all this like the stand or table it's all sitting on. I get the idea behind it, I get the proposed theory behind it (studied this kind of potential for propulsion decades ago at length), but in this specific example and video, I'm not buying it was the laser itself, even an 8W model 'cause from the theory behind this it would require a hell of a lot more power to move that tin foil even in visually noticeable degrees.
     
  4. heatlesssun

    heatlesssun [H]ard as it Gets

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    For the physicists around here, isn't the same principle behind a Crookes radiometer?
     
  5. umeng2002

    umeng2002 Gawd

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    This is well known physics here. When satellites are designed with large solar panels and whatnot, this effect is taken into account.
     
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  6. Lunas

    Lunas [H]ardForum Junkie

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    He has better videos... and he was having issues getting it to show up on camera his 2w laser just did not move it very much and when it hit the hair it caused the hair to start burning thus contracting... the foil barely moved a mm what was the most standout was when he let the air back in and he demonstrated the difference between near vacuum and with air drag on the movement...
     
  7. NExUS1g

    NExUS1g Gawd

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    Math or you're lying.
     
  8. Tiberian

    Tiberian DILLIGAFuck

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    Well I haven't done that kind of math since high school days so that's a wash there, but the information is available if you do the research like I did in early 1980s. Believe it, don't believe it, that's up to you.
     
  9. NExUS1g

    NExUS1g Gawd

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    Just half-joking. But I think two watts is enough to move it given the only appreciable opposing force is the tension in the hair.
     
  10. raz-0

    raz-0 [H]ardness Supreme

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    It's like a really shitty youtube version of a crookes radiometer

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