Circuit Analysis of a diagram with series and parallel circuits

AI Thread Summary
The discussion focuses on analyzing a circuit diagram with series and parallel components, where the equivalent resistance (Req) is calculated as 13.6 ohms and the total current (It) from a 10V supply is 0.74A. Participants emphasize the importance of using Kirchhoff's laws for circuit analysis and suggest calculating the potential drop across R1 to determine the current through other resistors. The potential drop across R1 is confirmed to be 3.7V, but there are discrepancies in the calculated currents through R2 and the parallel combination of R3 and R4. Further clarification on the potential at node Va is needed to resolve the current calculations accurately.
joshqg
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Homework Statement
Find the current through and potential drop across each resistors
Relevant Equations
It=Vt/Req
I found the Req which is 13.6 and also found the It which is 0.74. I'm having trouble finding the separate current and potential difference numbers.
circuit analysis.png
 
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What circuit laws have you learned? Any particular circuit analysis techniques?
 
Your Req is correct (well, I would keep more significant figures for more calculations). So now you know the current drawn from the 10V supply. That current flows through R1, so that gives you all you need to know about R1. Now calculate the Req for the resistors past R1 so you can see how the current divides between the two branches, and keep on going with the calculation. Please show your detailed work so we can keep checking it. Good so far! :smile:
 
berkeman said:
Your Req is correct (well, I would keep more significant figures for more calculations). So now you know the current drawn from the 10V supply. That current flows through R1, so that gives you all you need to know about R1. Now calculate the Req for the resistors past R1 so you can see how the current divides between the two branches, and keep on going with the calculation. Please show your detailed work so we can keep checking it. Good so far! :smile:
For I1 can I use 10V or do I need to find V1 by using the current I found? Also, to find Req for the other resistors do I need to add the 10 ohm and 5 ohm resistors and then solve the Req using the two parallel?

gneill said:
What circuit laws have you learned? Any particular circuit analysis techniques?
We've learned Kirchhoff's laws.
 
You've found the current that the 10 V supply delivers to the equivalent resistance of the network.
1578623693760.png

So you know that this current must be flowing though R1. What's the potential drop across R1? So what then is Va:
1578623835600.png

If you know Va, what's the current through R2 and R3+R4? And their potential drops?
 
gneill said:
You've found the current that the 10 V supply delivers to the equivalent resistance of the network.
View attachment 255387
So you know that this current must be flowing though R1. What's the potential drop across R1? So what then is Va:
View attachment 255388
If you know Va, what's the current through R2 and R3+R4? And their potential drops?
The potential drop off across R1 is 3.7 V. The current through R2 is 0.185. The current through R3+4 is 0.25
 
joshqg said:
The potential drop off across R1 is 3.7 V. The current through R2 is 0.185. The current through R3+4 is 0.25
Your potential drop across R1` is okay, but the other current values do not look good. What are you taking as the potential at node Va? It's certainly not the potential drop across R1!
 
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