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Is this circuit the same as this?

  • Thread starter pwi_rk14
  • Start date
  • #1
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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?
 

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Answers and Replies

  • #2
BiGyElLoWhAt
Gold Member
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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.
 
  • #3
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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?
 
  • #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:
  • #5
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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?
 
  • #6
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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?
Yes, and yes.
 

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