thevenin
I'm trying to find the Thevenin equivalent of the following circuit, but am unsure of how to find the Thevenin voltage/open circuit voltage. Can I just find the voltage across the current source and the voltage across the 4k resistor and add them together to get the open circuit voltage?
Yes, there will be no current through the 30V voltage source either. If there was, then that current would have no way to go to or come from if a is kept floating. This would violate Kirchoff's Current Law in node a.
If you add a load between a and b, then you are closing a loop and it becomes possible that a current flows through the 30V voltage source.
I would start by redrawing the circuit:
simulate this circuit – Schematic created using CircuitLab
Then use a source transformation:
Combine the resistors:
Transform back:
Finally combine the series components:
Best Answer
Yes, that's going to give you the right answer but finding those voltages requires a little thought. For instance you have to notice that the current through the 1kohm resistor is 9 mA and some of that comes via the 2k and some via the 3k so you have to proportion them appropriately AND keep the relevancy of the 45 volt source and 4kohm in mind.
It might be easier to solve it using superposition.