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Battery Voltage

  1. Oct 2, 2006 #1
    Hi, I just would like to make sure that my concepts are clear on voltage. Using a battery as an example, I have a couple of questions...The battery seperates the positive charges from the negative charges, which in result causes a seperation (voltage). Now, if the battery is connected to a load, the negative charge travels through the wire to the positive terminal, and opposite for the positive charge. Why and how is this voltage or emf moving the charges through the wire to the other termininal?
  2. jcsd
  3. Oct 2, 2006 #2


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    Electrical potential acts just like gravitational potential. You're familiar with the fact that a ball will roll down a hill, of course -- it's really the same concept for electric phenomena.

    A battery creates a difference in electrical potential -- in the same way that a ramp "creates" a difference in gravitational potential -- and electrons "roll down the hill" caused by this difference.

    In more specific terminology, the difference in potential at either end of a wire creates an electric field inside the wire, and this electric field causes electrons to move.

    Please note that in normal wires, the positive charges are fixed. No positive charges move through the wires. Positive charges (in the form of ions) do indeed move inside the battery, through the electrolyte, but they don't move through the wire.

    - Warren
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