Is this circuit the same as this?

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The discussion focuses on a circuit with three identical light bulbs and a fully charged capacitor, analyzing which bulb is the brightest. The original poster suggests that the brightness of the bulbs can be determined by examining the voltage drop across each component. They emphasize the importance of understanding current flow and potential differences at junctions in the circuit. The conversation confirms that the capacitor can be disregarded when fully charged, allowing for a simplified analysis of the circuit. Ultimately, the conclusion is that bulbs A and B can be considered in series with bulb C.
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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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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.
 
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?
 
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:
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?
 
pwi_rk14 said:
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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