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Homework Help: Circuit problem

  1. Apr 3, 2005 #1
    In the attachment, the capcitors are identical. Across which terminals would you connect a battery in order for all the capacitors to charge up?
    There are selections of AB, AC, or BD and none.

    The answer is none, but can anyone please explain to me why

    Attached Files:

  2. jcsd
  3. Apr 3, 2005 #2
    There is no path in which you can reach current to all the capacitors. Once you reach a capacitor, the current will stop at that point (over time).
  4. Apr 3, 2005 #3
    Thanks for your explanation, but can you elaborate on that a little more, please? I still don't understand why you cannot charge all the capacitors(not to the max) to an extent?
  5. Apr 3, 2005 #4
    Ok here is an example if the battery is connected between A+ C then the bottom capacitor will not charge, but the others will. This is because nodes B and D will be at the same voltage.

    The circuit can be redrawn to show the same thing works for A+B, and A+D.
  6. Apr 4, 2005 #5


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    Nodes A and C are always at the same voltage, so the capacitor between them never gets charged.

    - Warren
  7. Apr 4, 2005 #6
    If the two terminals of a battery are connected to the nodes A and C how can they be at [the same] voltages?
    Last edited: Apr 4, 2005
  8. Apr 4, 2005 #7


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    :rofl: I'm sorry, I didn't read the question that thoroughly.

    - Warren
  9. Apr 4, 2005 #8
    All is right with the world then. :smile:
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