Gary Kneisley wrote:
>
> A neat way to remember the formula is PIE.
>
> P=IE
>
> Power = I (amps) times Electromotive force (volts)
>
> thus
>
> 260 watts = 21.66 amps times 12 volts
>
> or
>
> 260watts/12volts=21.66amps
>
> Look what happens if your voltage is low....
>
> 260watts/10volts = 26 amps
>
> Gary
> Grafton, OH
> 1991 +8
>
Hi Gary et al,
When the voltage drops the headlamps no longer consume 260 watts. The
resistance of the bulbs stays the same (relatively, there is a change in
resistance with temperature of the filament), so when the voltage drops
the current decreases. A depleted battery (read low voltage) produces
dim headlights. A fully charged battery drives the current through the
headlamps that gives bright illumination. The highest current occurs
when the voltage impressed on the circuit is the highest (Ohm's Law).
Regards, Tony
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