4 ms·
Draws too much current. Older strands used to be parallel and were a frequent cause of fires. LEDs use less power but don't work well in parallel.
by whoopdedo 12y ago
Draws too much current. Older strands used to be parallel and were a frequent cause of fires.
LEDs use less power but don't work well in parallel.
- raldi 12y agoInteresting. And your theory seems to hold water: V=IR, so with constant voltage, current is inversely proportional to resistance, and the resistance of 100 bulbs in series is far far greater than 100 bulbs in parallel.
- mindslight 12y agoYour 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!.
- raldi 12y ago170?
- mindslight 12y agoThe 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.
- monochromatic 12y agoCouldn't higher-resistance bulbs be used?