The only thing you did "wrong" was to assume that the supplied answer is correct.Its been a while since I last worked with electric circuits.
Im trying to replace this circuit with the Thevenin equivalent.
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I get a Thevenin equivalent resistor of 25 ohms, the answer should be 3 ohms.
This is how I tried to solve it. What did I do wrong?
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How do you get that the voltage across the 24 Ω resistor is (v1 - 100 V)? That is the voltage across the top 2 Ω resistor (measured as the right side relative to the left side).Thank you. I guess the solution is wrong. Could you help me out with calculating the Thevenin equivalent voltage source? The answer should be 125V. I dont know how to do it. I tried with node voltage but I dont know how to do node voltage when I have a resistor (24 ohms) and a current source (3A) in the same branch. I get (v1-100v)/24ohms + v1/2 ohms but dont know what to do with the 24 ohms resistor and the 3A current source. also tried with the mesh current method, but I havent learned to do mesh current method with a current source.
Sorry. I dont know why I wrote 24. Silly mistake. I meant to type (v1-100V)/2 ohms.How do you get that the voltage across the 24 Ω resistor is (v1 - 100 V)? That is the voltage across the top 2 Ω resistor (measured as the right side relative to the left side).
Apply KCL at the node above v1.
BTW -- Thanks for tracking your units in your equations -- so very rare to see someone do that.
Okay, so [(v1 - 100 V) / 2 Ω] + [v1 / 2 Ω] is the current flowing out of the node. What is the current flowing into the node?Sorry. I dont know why I wrote 24. Silly mistake. I meant to type (v1-100V)/2 ohms.
I see. Its 3 Amps. Which gives us a total of 53V at the node above v1. The voltage over the 24 ohms resistor is 3A*24 ohms = 72V.Okay, so [(v1 - 100 V) / 2 Ω] + [v1 / 2 Ω] is the current flowing out of the node. What is the current flowing into the node?
It is certainly related to the node voltage method, but I don't know that I would go quite so far as to call it that -- but that's a matter of semantics, really.I see. Its 3 Amps. Which gives us a total of 53V at the node above v1. The voltage over the 24 ohms resistor is 3A*24 ohms = 72V.
We get Vth= 53V+72V = 125V. Thanks for the help. Now I can finally sleep
Does this still count as "node voltage method" ?
by Jake Hertz