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Alternating Current. (When can we see it?)

  1. May 24, 2009 #1
    Hello there my fellow chemical structures!

    I was just wondering the other day, while staring vacantly at a lighting fixture: How slow would the AC going back and forth through the light bulb have to be before you could see it flickering?

    Any information would be much obliged.

    Thanks in advance.
     
  2. jcsd
  3. May 24, 2009 #2

    Mapes

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    You might want to investigate http://en.wikipedia.org/wiki/Persistence_of_vision" [Broken]. A couple fine points with incandescent lighting: first, the filament will flicker twice for each AC cycle, since resistive heating is independent of current direction. Second, the filament won't go dark instantaneously but will cool down over a time period that depends on the thickness, material, and geometry of the filament. Empirically, I'd expect the minimum frequency to be on the order of 10 Hz, but I don't have a frequency generator handy; perhaps someone else does.
     
    Last edited by a moderator: May 4, 2017
  4. May 25, 2009 #3
    Thanks
     
  5. May 25, 2009 #4
    Incandescent bublbs don't easily show flicker because of the temperature of the filament. A flourescent bulb can be seen at 60 Hz.
     
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