Typically, only gear-heads, wannabe gear-heads, mechanics, electricians, automotive engineers and those of similar ilk wonder about how many watts will a headlight on a car consume. But, others may also be curious, and should know that where this question is concerned, some variables should first be considered:
- Make and model of automobile
- General electrical principle
- All the same, but different. In principle, the working of headlights in most modern automobiles is quite similar. However, they do vary from make-to-make. In other words, the answer to “How many watts will a headlight on a car consume?” can be generalized but not made specific where any given car is concerned. For example, in principle, headlights on a GM vehicle are wired in a basically similar fashion to those on a BMW, though but minor variances might exist.
- Stop messing with the wiring. Though ill-advised, many engineers and, more often, backyard mechanics toy with the electrical systems of cars. And, this of course can alter the answer to the question, “How many watts will a headlight on a car consume?” This should be considered before arriving at a definitive answer.
- I = E/R. General electric principles dictate certain finite possibilities. But, given the elaborate engineering of today’s cars, it should be known that there are numerous variables where the wattage consumed by headlights is concerned. So if in doubt of specifics, a manufacturer of any particular automobile should be consulted.
In short, however, the average watt consumption of an automobile headlight, in case you're ever asked in "Jeopardy," is 55 watts (all things considered).