# Node eqs help

Discussion in 'Homework Help' started by n_adam, Apr 5, 2014.

Mar 1, 2014
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Hi guys,

I am having trouble figuring out the right equations for the 4 nodes. Can someone tell me what am I doing wrong?

This is what I have so far.

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2. ### Jony130 AAC Fanatic!

Feb 17, 2009
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I don't see anything wrong with your nodal equation for node 4
I5 = I6 + 28A
(V2 - V4)/4 = (V4 - V3)/2 + 28A

But in your circuit you have 4 node, so to solve this circuit you need only 3 nodal equation. And one of the node you treat as a reference node (GND).

Mar 1, 2014
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OK I will try to solve it that way and let you know if I got the right answers.

Mar 1, 2014
19
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OK I tried to solve it using the node under v1 as a reference node but I still can't get the right answer. I simulated the circuit with multisim and v1 should be 60V, v2 86, and v3 13. I am still doing something wrong...

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5. ### Jony130 AAC Fanatic!

Feb 17, 2009
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Last edited: Apr 5, 2014
6. ### shteii01 AAC Fanatic!

Feb 19, 2010
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I have a question about v2. It seems to me that v2 is voltage drop across two resistors.

I think you are looking at v2 as being voltage drop across 4 Ohm resistor and I think that is wrong. I think v2 is equal to sum of voltage drop across 4 Ohm and v3.

Feb 19, 2010
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