Engineering Is i_0 Zero in This KCL Circuit Analysis Problem?

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The discussion revolves around a circuit analysis problem where the user is trying to determine the current i_0 in a KCL circuit with a voltage source of 54V. The user initially calculates a total current of 3A in one loop but becomes confused about the implications for the node where i_0 is located, questioning if it should be zero. Other participants clarify that having currents leaving a node without incoming currents can indicate negative values, suggesting that i_0 may not necessarily be zero. The user also notes the relationship between currents i_1 and i_2, indicating that i_2 equals twice i_1, and mentions a current source producing 9A. The conversation emphasizes the importance of understanding current direction and signs in circuit analysis.
ElijahRockers
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Homework Statement



8xi5q.jpg


if V_g = 54V

find i_0, i_1, i_2

The Attempt at a Solution



In the left most closed loop, Since the source voltage is 54, I assumed there must be a voltage drop across the 12Ω and 6Ω resistors equal to 54. This makes VΔ 18V.

Next I tried to KCL the node below it, but it immediately confused me. If the current around the closed loop is 3A (which is what I calculated by doing a KVL of that leftmost loop), then how can there be any more current flowing into that node? Shouldn't i0 be 0?

Then, even if it is, that means in the righthand part of the circuit, one node has three currents leaving it and none coming in, while another node will have three currents entering it and none leaving. The only way I can think of that happening is if all the currents are equal to zero, but surely this is not the answer...

Anyway, the only other work I could do was to note that the 10Ω and 5Ω are in parallel, so i2 = 2i1. Also, the current source is producing 9A, since the supplied current is supposed to be VΔ/2, but that doesn't seem to help my situation much.
 
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Shouldn't i0 be 0?
Yep! There is nowhere for the current to return...

one node has three currents leaving it and none coming in
That's just a sign thing. Currents can be negative.

i2 = 2i1. Also, the current source is producing 9A

You are on the right track -- keep going!
 

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