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Old 07-23-2018, 10:15 PM   #9
autostaretx
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Default Re: DRL bulb replacement?

25 w/13.5v = 1.85 amps
13.5 v/1.85 amp = 7.3 ohms
12v / 7.3 ohms = 1.64 amps
1.64 amp * 12v =19.73 watts

Yeah, close enough to 21 watts...

--dick (bulbs are not "ideal devices", their resistance changes a bit depending upon temperature)
((yes, i could'a used W=V^2/R or W=R*I^2, but i felt like walking it through))
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