# Thevenin Equivalent & Available Power???

1. Sep 10, 2016

### Marcin H

1. The problem statement, all variables and given/known data

2. Relevant equations
V=IR
Node Voltage
Thev/Nort

3. The attempt at a solution
So I set up my equations in the picture below, but I'm kinda confused about the Vx's in the equations. First, did I set these up correctly? If so, solving them I get that V2=0 which would mean my Voc is 0V which means Vthev=0. Is that even possible? Am I doing something wrong here?

2. Sep 10, 2016

### Staff: Mentor

That rectangle labelled -Vx, what is it?

3. Sep 10, 2016

### Marcin H

What? That's a dependent current source.

4. Sep 11, 2016

### Staff: Mentor

A Thévenin voltage of zero is okay. This still leaves you trying to determine Rth. There is not much use pretending to short-circuit the output to measure current—because regardless of the Thévenin resistance, that current is going to be zero because its voltage source is zero.

An equally-valid approach is to inject current into your circuit's outputand measure/calculate the voltage this causes at the output. You can then use this data in conjunction with the Thévenin model to calculate Rth.

⏩ So draw an independent current source adding a current Iin at terminal a and determine Vab.

it's a linear circuit model, so on paper you can do whatever you wish to it