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Voltage drop across resistors

  1. Mar 27, 2013 #1
    Hello,

    I am having conceptual difficulties trying to understand how voltage is dropped across a resistor. The whole idea of it is confusing to me, where does this voltage go?

    Could it be explained in terms of point charges and electric fields, which is how I am able to visualize potential difference.

    The way I see it, the positive charges move across a resistor and face some sort of resistance to their motion, but how does that relate to the charges losing potential?
     
  2. jcsd
  3. Mar 28, 2013 #2

    mfb

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    Voltage is not a material, it does not "go" somewhere.
    Where does the height of a ladder (not your height!) "go" if you climb it down?

    They need some energy to cross the resistor. Moving positive charges are quite rare.
     
  4. Mar 28, 2013 #3

    CWatters

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    Think of it in terms of power.

    Power = I ΔV.

    It escapes as heat.
     
  5. Mar 28, 2013 #4
    positive charges don't move as much as the electrons move to fill "electron holes"
     
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