Help with RC Circuits: 3 Resistors in Series

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Homework Help Overview

The discussion revolves around an RC circuit involving three resistors and capacitors, specifically focusing on the configuration of the resistors in steady state conditions.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants explore the reasoning behind the resistors being in series versus parallel after the capacitors are removed from the circuit. Questions arise about the implications of eliminating the capacitors entirely and how that affects the circuit's configuration.

Discussion Status

Some participants have provided insights into the behavior of the circuit at steady state, while others are questioning the interpretation of the circuit's layout after the capacitors are removed. There is an ongoing exploration of how to apply Kirchhoff's loop rule in the context of the problem.

Contextual Notes

Participants are navigating the assumptions related to the circuit's configuration and the effects of steady state on the components involved. There is a mention of specific capacitor values and the need to consider them in the analysis.

pyroknife
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Homework Statement


I attached the problem

I don't understand why the 3 resistors at the top end up being in series for part b. can someone explain that to me.

Homework Equations





The Attempt at a Solution

 

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After a long time, when the circuit reaches steady state, the capacitors will be charged to their steady state values and no further current will flow into or out of them. Essentially, as far as the current is concerned, they no longer exist in the circuit.

If you take your eraser and remove the capacitors, what doe the circuit look like?
 
Ohh i see thanks a bunch. But even if i erase the capacitors and have just a wire in their place, wouldn't it still look like the 3 are in parallel?
 
pyroknife said:
Ohh i see thanks a bunch. But even if i erase the capacitors and have just a wire in their place, wouldn't it still look like the 3 are in parallel?

By erase I mean eliminate completely. Leave no trace! Not even wires!
 
gneill said:
By erase I mean eliminate completely. Leave no trace! Not even wires!

Oh i see. part c of the question asks for the charges on the plates of the capacitors a long time after switch S is closed. If I play kirkoff's loop rule to the capacitor with the 10 microfarads, which resistors would I have to include in the equation?
 
wait never mind I wasn't thinking. "loop" so I just take one of the triangles at the top and apply the loop rule.
 

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