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john88
Sep4-08, 06:12 PM
1. The problem statement, all variables and given/known data



2. Relevant equations



3. The attempt at a solution

I trying to figure out a thevenin equivalent circuit

I want to calculate the current I so I cant get the resistance for the thevenin equivalent.

Im not 100% sure how to calculate I, can I use KCL on the node under the number -8.7V?

http://img98.imageshack.us/my.php?image=curfc7.jpg

Defennder
Sep4-08, 10:00 PM
That sure is a complex circuit. To find Rth, kill all the current and voltage sources and then measure the equivalent resistance between A&B.

KCL is valid everywhere. Is that -6.7 and -8.7 node voltages given by the question? If so, then you can easily find Isc. Also note that the 1mA source is connected in parallel with a short-circuited wire.

john88
Sep12-08, 12:02 PM
so if short circuit the system. Can I setup KCL on node A and then solve for I,
I = I(source) + I(R10).

But it seems odd to do so.

Defennder
Sep12-08, 11:20 PM
You got the equation wrong. It's IR10 = Isource + I. Be careful of the direction designated for Isc.

john88
Sep16-08, 07:52 PM
ok, got everything together now, ty for the help!