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What is the electric potential of Earth?

  1. Aug 3, 2014 #1
    What is the potential of Earth with respect to (wrt) infinity (C=710uF)? I am assuming that infinity is the correct reference here.

    Suppose a capacitor that's normally used in an electric/electronic circuit is
    a) discharged by connecting its two (2) terminals.
    b) then they are disconnected and the capacitor is held in dry air.
    c) then terminal 1 is connected to Earth, and is disconnected from Earth.

    Does this terminal 1 then have the same potential wrt infinity as Earth? Is charge then residing on the plate of terminal 1? What is then the potential of the other plate (terminal 2) wrt infinity and wrt terminal 1?

    Then if this capacitor's terminals are shorted together, is there a brief current flow? If the terminals are disconnected after the discharge current stops flowing, do both terminals have a potential wrt infinity? If the terminals are identical in size, is their potential now 1/2 that of the earth?

    I hope these questions make sense. Please explain why if they don't.

    Thanks for reading. Please let me know the answers if you know what they are.

    Please excuse me if I have posted this before. I sometimes forget.
  2. jcsd
  3. Aug 3, 2014 #2


    Staff: Mentor

    Regardless of the capacitance of the earth, since it has essentially 0 net charge its potential is 0 wrt infinity. The only time that you would get a significant potential wrt infinity is if you gave it a net charge.
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