What is the relationship between current and resistance?

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Homework Help Overview

The discussion revolves around the relationship between current and resistance in a circuit involving capacitors and resistors. Participants are exploring the behavior of current in relation to changes in voltage and circuit configurations.

Discussion Character

  • Conceptual clarification, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants are examining the implications of closing switches in the circuit and how it affects current flow through different resistors. Questions arise about whether the current remains the same across resistors and the role of the capacitor in the circuit.

Discussion Status

The discussion is ongoing, with participants providing insights into the behavior of the circuit components. Some have suggested that the capacitor may not influence the current flow significantly, while others are questioning the assumptions about current distribution in the circuit.

Contextual Notes

There is a reference to specific circuit conditions, such as the state of the capacitor after being charged and the implications of closing switches on current flow. Participants are also discussing a graph related to the problem, which may influence their understanding of the current behavior.

Gear300
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Question is in attachment below...I was doing fine from (a) through (c). When I got to question (d), it sort of got me stuck...wouldn't the current be the same for both resistors over time?
 

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After C has been charge up (ie. S1 closed for a long time). The Voltage across C is same as E, effectively you have an open circuit at C. So initially, when S2 is closed, there cannot be any current through R1 because potential difference across it is E-V_C = 0, but as C discharges through R2, V_C drops and now E-V_C >0 and so E will charge up C again via R1 (so current through R1 becomes non-zero). And so as C discharges through R2, E through R1 constantly charges C up again. I believe the net effect would be that C is just a spectator in this process.
 
Wouldn't the current running through R1 also run through R2 because there is an open circuit at C? And the process you described seems to run like you said in that last sentence...that C would remain a spectator. In that case, when S2 is closed, can C be ignored?
 
Found the actual graph (the attachment). The horizontal asymptote is above 0, I1 starts at 0A and I2 starts at a positive value current. I was thinking both I1 and I2 would be under the horizontal asymptote; why is I2 above it?
 

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