Battery connected to capacitors in series

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Homework Help Overview

The discussion revolves around a problem involving a 12-V battery connected to three capacitors in series with capacitances of 4.0 µF, 14 µF, and 33 µF. Participants are exploring how to approach the calculation of voltage across the capacitors.

Discussion Character

  • Exploratory, Conceptual clarification, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the method of calculating equivalent capacitance for capacitors in series and question whether capacitances need conversion from microfarads to farads. There is mention of using the charge-voltage relationship (Q = UC) and the concept that all capacitors in series share the same charge.

Discussion Status

Some participants have provided guidance on using the charge equation and the relationship between voltage and capacitance, while others express confusion about determining the equivalent capacitance and how to proceed with the calculations. The discussion is ongoing with various interpretations being explored.

Contextual Notes

One participant notes the need to clarify the specific question regarding the voltage across the 33 µF capacitor, indicating that the original problem may have lacked detail. There is also uncertainty about the textbook references for the equations involved.

matt72lsu
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Homework Statement


A 12-V battery is connected to three capacitors in series. The capacitors have the following capacitances: 4.0uF, 14uF, and 33uF.


Homework Equations



R = V/I

The Attempt at a Solution


I'm thinking you add the capacitances since they are in series (do i need to convert them from uf to F?) but I'm not sure what to do after that
 
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you don't add them. This should be in your textbook somewhere. You can derive the equation to use with Q = UC (charge = potential difference * capacitance), together with the fact that all of the capacitors have the same charge (if they started out empty) because the same current has gone through them always.
Compute the potential difference across the 3 capacitors with Q=UC and the sum of them should be 12 V
 


I forgot to add the actual question of what they are looking for: Find the voltage across the 33uF capacitor
 
Last edited:


Ok so I know you use Q = CV. But I am still confused about how to find C.
 


anybody?
 

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