Voltage drop in Capacitors and Lightbulbs

AI Thread Summary
The circuit features a total voltage of 6 volts from the batteries, with two identical bulbs in each branch. When the circuit is first connected, the voltage across the bulbs varies as the capacitors charge. According to Kirchhoff’s loop rule, the potential changes must sum to zero, indicating that when fully charged, there is no voltage difference across the bulbs, causing them not to light. The discussion highlights confusion about the voltage readings during the charging process and the implications for the bulbs' brightness. Clarification on these points is needed for accurate understanding and completion of the assignment.
kkroo
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The batteries in this cicuit create a total voltage difference of 6 volts across the circuit.
Assume A is 6 vols in each circuit,
Record the voltage of the lettered locations at the time when the circuit is first connected, and later when it is fully charged


Note: bulbs below are identical
PHP:
       |------A (Bulb)--B---(Bulb)----C--| |--D--|
       |                                         |
      ---                                        |
       -                                         |
       |                                         |
       ------------------------------------------

PHP:
       |------A--| |--B---(Bulb)--C---(Bulb)---D--| |--E--|
       |                                                  |
      ---                                                 |
       -                                                  |
       |                                                  |
       ----------------------------------------------------

Any ideas?

Thanks
 
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Hi kkroo! Welcome to PF! :wink:

Show us what you've tried, and where you're stuck, and then we'll know how to help! :smile:
 
Hello,

I know that the Kirchhoff’s loop rule says the sum of the potential changes in the circuit must be zero. I also know that when the capacitor is fully charged, there is no potential difference bwtween the bubls because they don't shine. Here is what I think so far, but I have no idea if its correct.

Charging:
PHP:
       |------6 (Bulb)--3---(Bulb)----0--| |--0--|
       |                                         |
      ---                                        |
       -                                         |
       |                                         |
       ------------------------------------------

Charging:

PHP:
       |------6--| |--6---(Bulb)--3---(Bulb)---0--| |--0--|
       |                                                  |
      ---                                                 |
       -                                                  |
       |                                                  |
       ----------------------------------------------------

Charged:
PHP:
       |------6 (Bulb)--6---(Bulb)----6--| |--0--|
       |                                         |
      ---                                        |
       -                                         |
       |                                         |
       ------------------------------------------

Charging:
( aim especially stuck on this one, I know the opposite capacitor plates should have the same charge, but I know there can't be a potential difference between the bulbs.
PHP:
       |------6--| |--0---(Bulb)--0---(Bulb)---6--| |--0--|
       |                                                  |
      ---                                                 |
       -                                                  |
       |                                                  |
       ----------------------------------------------------

Any ideas? Please help as soon as you can, this is due in an hour and a half.

Thanks
 
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