# thevenin with dependences source-help

Discussion in 'Homework Help' started by amichayfeldman, Jun 23, 2013.

Jun 23, 2013
10
0
2. ### WBahn Moderator

Mar 31, 2012
18,087
4,917
Okay, now that you've shown us what you need to do, how about showing us what you have done so far?

This is "Homework Help", not "Homework Done For You"

3. ### amichayfeldman Thread Starter New Member

Jun 23, 2013
10
0
i tried to do V-open circuit and I-short circuit but i didnt succeed to get answer... i am not sure about the way to get the answer with dependence source thevenin method..

4. ### WBahn Moderator

Mar 31, 2012
18,087
4,917

How can we possibly help you figure out where you went wrong unless you show your work?

Jun 23, 2013
10
0
6. ### WBahn Moderator

Mar 31, 2012
18,087
4,917
I'm not seeing any image.

But if you are turning off sources to determine the equivalent resistance or to do analysis via superposition, you open circuit current sources (i.e., set the current to zero) and short circuit voltage sources (i.e., set the voltage to zero).

7. ### amichayfeldman Thread Starter New Member

Jun 23, 2013
10
0
i have pasted link to the image....

8. ### WBahn Moderator

Mar 31, 2012
18,087
4,917
I still can't see it.

Why won't you just attach the image to your post. That way it will be stored on the AAC server and we don't have to worry about it going away at some point in the future from the external server. It also makes it easy for people access it and makes it so that they don't have to worry if the third-party site is going to try to play games with their machine or upload a few hundred cookies.

Jun 23, 2013
10
0
10. ### t_n_k AAC Fanatic!

Mar 6, 2009
5,448
783
The integration of what appear to be annotated DC current & voltage sources with AC reactances is somewhat confusing. Are they meant to be DC sources or AC sources?

11. ### WBahn Moderator

Mar 31, 2012
18,087
4,917
That was my initial thought. But I don't see anything that prevents them from being phasor voltages and currents parameters. This is strongly indicated by the fact that the use of phasor impedances implies operation at one specific frequency (i.e., sinusoidal steady state). Since the values are not consistent with DC (a frequency of 0), we have to assume that the voltage and current sources are all specified at the same frequency that the impedances are for.

12. ### t_n_k AAC Fanatic!

Mar 6, 2009
5,448
783
@ amichayfeldman

"Ix-1=-12"

Why do you think this relationship doesn't make sense? Is it reasonable to equate current to voltage?

EDIT:

Actually I see what you probably have done now. The loop equation for the 12V source, the 1 ohm resistor and the 4A current source.

It looks like you have

"Ix*1=-12"

Can you see why this is incorrect? What about the voltage drop across the 4A source?

In any event it should be clear with node A open Ix is simply 4A.

Last edited: Jun 26, 2013