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Your intuition is correct, but a minor nit: bulbs aren't linear devices and don't have a fixed resistance. At low power, a bulb will look pretty close to a short circuit (it's just a piece of tungsten wire, after all). As power increases, the filament temperature rises and so does its resistance. This is why bulbs generally burn out when turning on - 170V across a mostly short circuit, with most of the resistance being in whatever section of the filament is most worn through, so most energy is dissipated at a single spot. poof!.


170?


The nominal voltage on an AC power line refers to the "RMS" average of the waveform. The peak voltage of a sine wave is sqrt(2)*RMS. Presumably bulbs tend to blow when they're turned on while the voltage is near a peak.




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