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noppawit
Jul12-09, 04:44 AM
I'm solving by using superposition, I would like to ask that my solution is correct or not.

By the way, the question is "Find v0"

http://www.wisheyebio.com/uploads/Picture1.png

cepheid
Jul12-09, 11:38 AM
I don't know about superposition, but if you use KCL at the top node, you have three branches:

The left branch has the current source and two resistors.

The right branch has the voltage source and two resistors.

The middle branch has the remaining resistor.

KCL says that:

current going into node = current coming out of node

which, in this case means:

current in left branch + current in right branch = current in middle branch.

I called the current in the right branch i0, which makes v0 = i0R. I get a significantly different answer (-1.00 V), which I confirmed using a circuit-solving program.

CEL
Jul16-09, 08:10 AM
I'm solving by using superposition, I would like to ask that my solution is correct or not.

By the way, the question is "Find v0"

http://www.wisheyebio.com/uploads/Picture1.png

You made two mistakes in the second equation. Since i_x is entering the plus sign of the voltage source, it should enter the equation as +9V, instead of -9V.
Also, R + R + \frac{2}{3}R = \frac{8}{3}R, not \frac{32}{3}R

Redbelly98
Jul16-09, 08:59 AM
IIRC, when treating the 9V source you would replace the current source with an open circuit, not a short. So the 2/3 R was incorrect to begin with.

CEL
Jul16-09, 01:02 PM
IIRC, when treating the 9V source you would replace the current source with an open circuit, not a short. So the 2/3 R was incorrect to begin with.
You are right.