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Re: light bulb and tannins



> Date: Fri, 19 Jan 2001 13:58:32 -0800
> From: Richard R <email2me1 at home_com>
> 
> Scott, they mean brightness 75watt of Incandescent light bulb while it uses 
> only 20watts. It's only to compare. So you use the 20watt number.
> Bob, you don't have to discount anything. Number of Watts has nothing to do 
> with output of the light bulb.
> It is like this : P = U x I ( P= V x I in Canada ), Power = Voltage x Current

But if the lamp and ballast together are rated 20W, the lamp may be
17W and the ballast 3W.  Also, lower wattage fluorescent lamps are
generally less efficient than higher wattages (probably correlates to
the length of the arc tube).  If you have a 20W conventional
fluorescent lamp, the ballast wattage is not included in the 20W
rating.

Best regards,
Bob