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Is this circuit the same as this?

  1. Mar 27, 2014 #1
    The circuit includes three identical light bulbs and a capactior that is fully charged. The power supply provides a steady potential difference. Which light bulb(s) is brightest? I attached the diagrams.

    My answer is C. Either that or A and B.
    Are my rewritten drawings equivalent to the original?
     

    Attached Files:

  2. jcsd
  3. Mar 27, 2014 #2

    BiGyElLoWhAt

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    Consider: What's the voltage drop across Resistor A, B, C and the capacitor in the origional. Then compare that to the other 2. Remember wire has a 'negligible' resistance, so across bare wire the potential has to be the same. I'm not answering your homework for you, though.
     
  4. Mar 27, 2014 #3
    in the original diagram, after current flows through A and through B, it has to go through the horizontal bar in the middle. What happens there, do they cancel?
     
  5. Mar 27, 2014 #4

    BiGyElLoWhAt

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    Does current flow through the middle? Current flows from higher potential to lower potential, right? Kind of like a ball at the top of a "potential hill". Label the left junction point 1 and label the right junction point 2 and figure out what the potential is at the points. Then post the current between the to points.
    *Edit: The junctions after A and B respectively
     
    Last edited: Mar 27, 2014
  6. Mar 27, 2014 #5
    Can I pretend the capacitor isn't there since it's fully charged?
    And if I do, would A+B be in series with C?
     
  7. Mar 27, 2014 #6
    Yes, and yes.
     
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