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With the water flow analogy

  1. Feb 29, 2008 #1
    What are the differences between the flow of water and current flow ?

    Besides the fact that the direction of current flow is opposite to the flow of e- where water molecules move in the same manner as flow of water...

    many Thanks.
  2. jcsd
  3. Feb 29, 2008 #2


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    The analogy works well with simple voltage sources and resistors, but cannot be used to model semiconductors, antennas, and many other electrical phenomena.

    For simple circuits, you are totally free to imagine that the current in a wire is a movement of positive charge high potentials to low potentials. In fact, the answers you'll get are exactly the same as those you'd get when considering negative charges moving the opposite way. When you get into semiconductors, the symmetry breaks down, however.

    - Warren
  4. Feb 29, 2008 #3


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    Foamy water analogy? Bubbles moving opposite way to water, no?
  5. Feb 29, 2008 #4

    Andy Resnick

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    Let's see: how about there's no analogy to magnetic field in fluid flow. There's two equivalent ways to describe an electrical circuit: the Thevenin and Norton eqvuivalent circuits; I'm not sure there's anything like that for fluids. Circuits can have rectifying elements, not so in fluids. Fluid flow involves concepts like stress and turbulence, those do not occur in electrical circuits, AFAIK.
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