How do you find the current going through a weird circuit?

AI Thread Summary
To find the current in a complex circuit, the user has labeled currents through each resistor and set up equations for two loops (ABC and BDC). They seek to solve for currents i2 and i5, expressing concerns about the number of variables involved. Suggestions include checking the signs of the currents and considering the delta-wye transform, despite it not being covered in their curriculum. Understanding the derivation of the delta-wye transform may provide insights into solving the circuit. The discussion emphasizes the importance of correctly applying circuit laws and transformations to simplify the problem.
giantf
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Homework Statement


3d249874d6.png


Homework Equations


at point C:
i2 - i3 - i4
i2 = i3 + i4[/B]

The Attempt at a Solution


I labeled all the currents going through each resistor in the picture[/B]

for loop ABC:
2000i1 = 3000i2 + 4000i3

for loop BDC:
3000i5 = 2000i4 + 4000i3

at point C:
i2 - i3 - i4
i2 = i3 + i4

at point B:
i1 + i3 - i5
i5 = i1 + i3


This is all I've been able to do so far for this problem. How would I solve for i2 and i5 which go through resistor 2? If I add the two loops (loop ABC and loop BDC) I would get a lot of variables and I'm wondering if I'm even doing this correctly
 

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Google "delta-wye transform"
 
phinds said:
Google "delta-wye transform"
Would that help? We haven't learned anything about that, and it's nowhere in the textbook, not sure if I'm allowed to use things from outside the curriculum
 
Try ABCD for another loop.

Also check your signs for BCD. The currents are not in the same direction so one is negative.
 
giantf said:
Would that help? We haven't learned anything about that, and it's nowhere in the textbook, not sure if I'm allowed to use things from outside the curriculum
Yes, but if you study the DERIVATION of the delta-wye transform, it will show you how to attack your circuit.
 
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