You can have a bad wire or with pinhole in the insulation and have a couple of good strands of wire left and pass an ohm test but it wont allow enough current to power the light.
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This is WHY as I said you check these UNDER LOAD. A "2 strands left" wire UNDER LOAD will NOT flow the current it is supposed to flow and STILL MAINTAIN "no" voltage drop.
Ya know I really effing get TIRED of trying to teach ohms law basics to some of you guys. Go learn some of it. There are other laws that go with Ohm's Law, and "Kirchoff's Law" is just one. Google it. They are real, actual scientific "laws" of "how **** works" They were invented by really old guys one hell of a long time ago, and guess what? It all still holds true today. The DIFFERENCE today, is, we now have easy, inexpensive access to VERY accurate digital voltmeters, which were not available when I was a "kid," and certainly not when these laws were written
A light bulb will NOT show up a few tenths of a volt drop. There is ONLY one way, short of expensive laboratory equipment to test fractions of an ohm resistance, and that is using a good voltmeter with the circuit UNDER LOAD
