Top 10 Amazing Physics Videos (Wired.com)

Discussion in 'Science' started by slipkord, Sep 9, 2008.

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  1. slipkord

    slipkord Member

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    Last edited: Sep 9, 2008
  2. MR CHILLED

    MR CHILLED D'oh!

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    Rofl! That's brilliant.....I could watch the tesla music coil for hours.....and the mythbuster voice thing was brilliant - I'd never seen that before, I thought you could only make your voice pitch higher.
     
  3. OP
    OP
    slipkord

    slipkord Member

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    yeah I hadn't seen that Mythbusters one (then again I've missed plenty), but you're right - it never occurred to me to think about a gas that produces the opposite effect to helium :lol:
     
  4. glimmerman

    glimmerman Member

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    Hahaahh how farkin awesome is the musical fire :p

    And the super conducting magnets were pretty fascinating!
     
  5. Whisper

    Whisper Member

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    Thanks for the link skiplord.

    I didn't quite get the tesla music coil thing.

    Intellectually I understand what supposedly happening, but buggered if I can anything all that exciting.

    Were where the sparks landed meant to correspond to a particular note, or what? Not that I could see where they landed or what they were hitting, at least not on my screen. YMMV.
     
  6. Narcoticx2

    Narcoticx2 Member

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    From the ones i have watched I thought the music came from the frequency of sparks and not where they're hitting...
     
  7. Assasinator_2

    Assasinator_2 (Banned or Deleted)

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    To quote wikipedia:

    Which, as an electrical retard, I think means it is how many times per second it sparks, rather than anything to do with AC frequency or anything.
     
  8. dakiller

    dakiller (Oscillating & Impeding)

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    I'm no Tesla coil expert so there is probably some valid reason why they do it this way, but if it is done it via PWM then that means that the arc is being pulsed on and off at a set rate, like 41khz but you change the amount of time each individual pulse lasts (duty cycle) so you can modulate lower frequencies into the carrier frequency

    This wiki picture
    shows what it would look like
     
  9. Bastard Child

    Bastard Child RIP

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    Pure rubbish, if that's the only explanation they give.

    I don't know how many of these old links still work: http://forums.speedlabs.org/index.php?topic=1444.0
     
  10. phrosty-boi

    phrosty-boi Member

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    Don't care how they do it, but the tesla coil video is awesome, theres a few on youtube from a user called voltmiester which are kinda cool
     
  11. FuzzyKaos

    FuzzyKaos Member

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  12. Jaws_au

    Jaws_au Member

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    Indeed - it's a pressure/temperature drop which causes the condensation.

    Certainly don't have to be going supersonic - you can see the effect (though not quite as spectacularly) at airshows when aircraft do high-G manoeuvres.

    A *more* spectacular example are the cloud-spheres you can see in footage of Pacific nuclear testing.
     
  13. the scotsman

    the scotsman Member

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    Thanks for the link, that page is great!

    I've never seen that Mythbusters one...I've seen him suck on the helium often enough, but the other stuff...I lol'd! :lol:
     
  14. Eggbert69

    Eggbert69 Member

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    That superfluid thing was really interesting... How exactly does it flow out of the cup though because it has 0 viscosity? Does it latch onto the glass and continue to spread up or something? Little bit lost here ... :confused:
     
  15. neutralizer

    neutralizer Member

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    I think your correct on that count with the super fluidity, the only other option is that it somehow seeps through the bottom of the beaker but I would have thought that the amorphous nature of glass would make that very unlikely.

    Very curious to know the answer as well :thumbup:
     
  16. MaskedSamurai

    MaskedSamurai Member

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  17. cysp

    cysp Member

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    I dont understand why a superliquid will have the 'urge' to climb out of a beaker even if its viscosity is 0?
     
  18. Bastard Child

    Bastard Child RIP

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    It's not climbing, it's wanting to lay itself out to an atom's thickness (no viscosity, no surface tension, no friction between the superfluid and vessel wall) :thumbup:

    As for dripping out - think of heat as vibrating atoms. At 2 degrees above absolute zero most of the vibration is gone, and with zero viscosity it's easily able to slip through porous containers (video quote - "unglazed ceramic bottom").
     
  19. dohzer

    dohzer Member

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    The zero gravity water sphere ones remind me of a NASA video where they have a guy popping a water bomb in a diving aircraft (zero gravity).
     

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