Berkeley CSUA MOTD:Entry 16555
Berkeley CSUA MOTD
2017/10/18 [General] UID:1000 Activity:popular

1999/9/20-21 [Science/Electric] UID:16555 Activity:high
9/18    Does a burned out lightbulb consume energy?
        \_ Boosting car stereos again danh?
        \_ burned out bulb == broken tungsten == air as conductor ==
           extremely high resistance == next to no current flow == no.
           \_ you mean 'practically no'
           \_ Or can I say since there is still a very little capacitence on
              still flow if it's hooked up to an *AC* supply, so it still
              the two sides of the broken tungsten, two very small currents
              consumes very little energy?
              \_ good point, i didn't think of that but i believe that
              \_ negligible, given that there is a lot more tightly coupled
                 copper wiring in the electrical cords, house wiring, etc.,
                 to add to the capacitance, in addition to higher dielectric
                 constant of the insulators.
                 the dielectric coefficient of air is very low.
                 air.  I meant a current flowing from the AC outlet to the
                 tip of one of the two broken tungsten wire that's connected
              \_ No, I didn't mean a current flowing across the insulating
                 to the "live" outlet.
                    are separated then current will flow through the
                    tungsten if you consider air as a high resistance
                 \_ it's the same answer.  if the two pieces of tungsten
                    conductor or a dielectric.  But these are just trace
                    quantities.  take an ee class.
2017/10/18 [General] UID:1000 Activity:popular

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