Voltage of a battery and capacitors are the same

AI Thread Summary
In a circuit with a 12-volt battery and multiple capacitors, the voltage across the capacitors depends on their configuration. If connected directly to the battery, they can charge to 12 volts, but this is not always the case for all capacitors in a circuit. Adding a 4-volt light bulb acts as a resistor and may slow the charging process but does not change the final voltage across the capacitors if they are not LEDs. Capacitors in series do not have the same voltage across them, as this would violate charge conservation principles. To analyze such circuits, understanding charge conservation, the relationship between charge (Q), capacitance (C), and voltage (V), as well as the uniform potential in wires is essential.
oneplusone
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I was watching this video: http://www.youtube.com/watch?v=P8A1U-RZDao&index=7&list=PLLUpvzaZLf3Jv7AjU5pfY8s25-QBCfdIZ
and at around 6 minutes, I got confused. Ill summarize it below in case the link does not work:

If you have a circuit which consists of a battery which is 12 volts, and a lot of capacitors…what is the voltage of the capacitors? Are ALL of them 12 V regardless of how they're set up, and the size of it? I heard something about capacitors taking their "Maximum voltage" always.

Also, how would this change if you add a 4V light bulb?
 
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Did you mean to link the video "Dielectrics in Capacitors and Otherwise" or something else? The video does not look related to your questions.

oneplusone said:
Are ALL of them 12 V regardless of how they're set up, and the size of it?
It depends on the circuit. If their terminals are connected to the terminals of the battery (via a cable as in 6:00), they will charge to 12 V.

Also, how would this change if you add a 4V light bulb?
It acts like a resistor, and will slow the charging process. It should not change the final voltages if it is a regular light bulb (i.e. not LEDs).
 
I can't find the correct video for some reason . I ll check later.

Suppose you have something like this:

Figure_20_05_10a.jpg


and it's connected to a battery . Would ALL the capacitors have the same voltage across it?
I'm mainly confused on problems like: "you stick a 12 volt battery to a circuit like this…now find the capacitance of each capacitor". Like what would you need to know to solve it?
 
Would ALL the capacitors have the same voltage across it?
No.
As an example, if the leftmost two capacitors would both have 12V across it, the total voltage across this side would be 24V - but we know the two sides have a difference of just 12V.

In addition, the same voltage for both capacitors would violate charge conservation if we start charging it from zero.

Like what would you need to know to solve it?
Just charge conservation, Q=CV and knowledge that the potential is the same everywhere in a wire.
 
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