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Generators and electrons

  1. Aug 2, 2008 #1
    The man who trained my to perform electrical construction had been doing that kind og work for over 30 years.

    We always wanted to know just where the electrons come from.

    You have a generator pumping a flow down the wire, but those electrons have to come from somewhere.

    so..... where does a generator get all those electrons from?
  2. jcsd
  3. Aug 2, 2008 #2


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    The electrons are in the atoms of the conducting material. Your description applies only to DC. When you have AC, the electrons oscillate rather than move in ome direction.
  4. Aug 2, 2008 #3
    let me guess

    60 times per second haha.

    I'll tell him and see if he understands is.
  5. Aug 2, 2008 #4


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    Staff: Mentor

    And in DC, the electrons come from the other wire...
  6. Aug 2, 2008 #5


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    The electrons were always present in the metal wiring. It's just a matter of generating a force to move them. AC or DC doesn't matter.
  7. Aug 3, 2008 #6

    Andy Resnick

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    Presumably you have a closed circuit- the electrons simply travel around the circuit. It is not required to 'create' electrons.
  8. Aug 4, 2008 #7
    Another way to try and understand it is to consider a hydraulic cycle as a metaphor.

    The hydraulic system is pumping a fluid around in a loop. Where does the hydraulic fluid come from? It's beside the point when you consider that the actual work is done by the PRESSURE, and not the fluid. Same goes for electrons.. the generator doesn't generate electrons, it generates electron flow.

    Consider this contrast view of both systems;

    You generate the power by pushing the fluid with a specific force...
    You generate power by pushing the electrons with a specific force...

    The pump pushes the fluid around the hydraulic lines...
    The magnetic rotor pushes the electrons around the coils...

    The hydraulic pump pushes fluid through the lines, and the power comes from the pressure of the fluid...
    The generator pushes electrons through the wires, and the power comes from the pressure of the electrons...
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