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An electric current question

  1. Nov 3, 2012 #1
    Hi, all.
    There's a thought flashing through my mind yesterday.
    Sorry for my lack of knowledge. The thought must be something wrong.
    Can anyone correct it? Thanks
    If there is a 3000000km long power cable, and the cable is pulled to 3000000km away from the earth.
    A power source connected on one side A of the cable on the Earth keeps outputting the electric current, and the switch of side B on the cable (away from earth 3000000km) is close. And there's a "current detector" on the cable away from side A by 1km. Does the detector detect the current?
    At a specific time, if the switch of side B starts to open, does the current start to go from A simultaneously?
    If so, people can open and close switch of side B to let people on side A know Morse code .
    If the cable is 1LY long, will transmitting message to 1LY away instantly comes true?
  2. jcsd
  3. Nov 3, 2012 #2


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