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GriffinRU
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Join Date: Oct 2005
11.19.2006, 01:00 AM

Quote:
Originally Posted by BrianG
I just read the that HSW article and I didn't particularly like their lightbulb example. The way it was stated led the reader to believe a 100W lightbulb will always produce 100W no matter the applied voltage.

The incandescent lightbulb is also a bad example because the filament does not have a linear resistance either. Its resistance is close to 0 when no current is flowing (off) and the resistance increases as it heats up from the current flow. Incidentally, this is why a bulb amost always blows when you first turn it on - from the initial inrush of current while the filament resistance is lowest.
100W of equivalent optical power, which will be based on temp of filament, which has its max at say 5000K then it melts...

Artur

P.S. howstuffworks -> internet is fantastic :)

Last edited by GriffinRU; 11.19.2006 at 01:04 AM.
   
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