wow sorry to be askign so many noob questions, but now its about LED's. ok here is what i come up with as far as choosing a resist to use for a red LED. 9v batt, 1.7 voltage drop and 20 milliamps = 365 ohm resist. now a friend of mine said he uses 4 LED's, 1 9V batt, and 4 1 ohm resistors(blue,blk, brwn, blk, gold) in parallel and has never burnt up a LED and the batt lasts for about 72 hrs. the LED colors are red, white, and 2 L-95's. i told him according to what i come up with he should be using less resistance. but does it really matter when dealing with such low voltage?
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