Alternating Current. (When can we see it?)

AI Thread Summary
The discussion centers on the visibility of flicker in alternating current (AC) light bulbs. Incandescent bulbs flicker twice per AC cycle due to the filament's resistive heating, but the filament does not cool instantaneously, affecting visibility. The minimum frequency at which flicker can be perceived is estimated to be around 10 Hz, although fluorescent bulbs can show flicker at 60 Hz. The temperature of the filament in incandescent bulbs contributes to their reduced flicker visibility. Understanding these factors is essential for recognizing how AC affects lighting.
ScienceNerd36
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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.
 
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You might want to investigate http://en.wikipedia.org/wiki/Persistence_of_vision" . 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.
 
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Thanks
 
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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