# Finding the short circuit current

Discussion in 'Homework Help' started by Mingosteen, Sep 25, 2015.

1. ### Mingosteen Thread Starter New Member

Sep 25, 2015
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0
Hi everyone!

I have a question regarding finding short circuit currents. We were asked to find the short circuit current for point ab (remove the R resistor and short circuit that path.) for the 1.2A circuit. My prof told us that the short circuit is just 1.2A. But for the next circuit, see attached 11V circuit, we were asked to find short circuit current for point ab and I tried to apply source transformation to the 11V and 1 ohm resistor to make it to a current source, 11A parallel with the 1 ohm resistor and I put the short circuit current ab, as 11A but the answer was 2.75A. Why is the short circuit current for the 1.2A circuit = 1.2A but the short circuit current for the 11V circuit is not 11A?

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2. ### Jony130 AAC Fanatic!

Feb 17, 2009
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But those are two different circuit so I don't understand your question?
Notice that in 11V circuit you have a current controlled current source (CCCS) not VCCS as in 1.2A circuit.

3. ### WBahn Moderator

Mar 31, 2012
23,391
7,099
I think the underlying problem is that someone (your prof) told you the answer, but you didn't actually work the problem. So you are making a wildly unjustified assumption that if a circuit has a current source anywhere in it that if you short circuit some element anywhere else in the circuit that the full current from the source flows through the short. Does that really make any sense?

So try actually working the problems.