Understanding how to re-draw circuits

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Discussion Overview

The discussion revolves around understanding how to analyze and redraw electrical circuits, specifically focusing on identifying series and parallel components. Participants seek clarification on reading circuit diagrams and simplifying them to find currents and voltages.

Discussion Character

  • Homework-related
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant expresses difficulty in reading the circuit and understanding how to identify series and parallel components, asking for guidance on redrawing the circuit.
  • Another participant suggests adding a 20 V battery to create a loop for analysis.
  • Some participants propose simplifying the circuit step-by-step, indicating that R5 and R3 are in parallel and can be combined into a single resistance.
  • There is a caution raised about losing individual voltages and currents when combining circuit elements.
  • A participant mentions using Kirchhoff's Current Law (KCL) at specific points to solve for voltages Va and Vb, suggesting that this would make finding currents easier.
  • One participant reiterates the method of simplifying the circuit and poses a question about how to find Vb if a specific resistor (R5) were absent, indicating that the absence of R5 would alter the currents I2 and I3.

Areas of Agreement / Disagreement

Participants generally agree on the approach of simplifying the circuit step-by-step; however, there are differing opinions on the implications of combining circuit elements and the effects of removing specific components, indicating unresolved aspects of the discussion.

Contextual Notes

Participants express uncertainty regarding the effects of combining resistors and the dependencies of current values on the presence of specific components, highlighting the complexity of circuit analysis.

Who May Find This Useful

Students learning circuit analysis, individuals seeking to understand electrical engineering concepts, and those needing assistance with homework related to circuit diagrams.

Lopez
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Homework Statement



I need to find I1,I2,I3,Va,Vb but i don't even know to read the circuit. i know how to to do series circuits and parallel circuits but not this. How do i read this circuit and know which ones are in parallel or in series. is there a way to re-draw it? I have the solution and answer. Therefore i don't need the step by step solution since i already have it,is just that it doesn't explain why they did it that why.
These are the I1=4A ,I2=1.33, I3=.67, I4=2.67,va=8.0,and vb i don't know.
Please help understanding what is going on in this circuit.
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If you need a loop, put in a 20 V battery with the positive plate connected to E. Connect the negative plate of the battery to the 3 grounds at the bottom of the diagram.
 
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I would work my way up from the bottom, simplifying bits and pieces as I go. R5 and R3 are in parallel, right? So you could combine those two resistors into a single resistance. Keep chipping away at it until you have a single loop.
 
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If you combine circuit elements you will lose that components individual voltage and/or current.

I reccoend doing a KCL at Va and Va. Then solve for Va and Vb, and the currents will be easy to find.
 
thanks for the tip
 
Mark44 said:
I would work my way up from the bottom, simplifying bits and pieces as I go. R5 and R3 are in parallel, right? So you could combine those two resistors into a single resistance. Keep chipping away at it until you have a single loop.
if i do ((R5||R3)+R2)||R4 and this would be in series with R1 right? now to get Vb i think i would do Vb=R5(I2-I3) but what if that R5 was not there then how would i solve for vb
 
Lopez said:
if i do ((R5||R3)+R2)||R4 and this would be in series with R1 right? now to get Vb i think i would do Vb=R5(I2-I3) but what if that R5 was not there then how would i solve for vb
If R5 was not there then I2 and I3 would change. you cannot solve for an unknown value with unknown values
 

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