Kirchoff's Law: Which Direction Does the Current Flow?

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atwong713
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Homework Statement


determine which way the current goes

Homework Equations


kirchoff's current law


The Attempt at a Solution



i say that it is moving away because if i say its positive going into element1 then since its negative its going out of element1 so its moving away from A
 

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Based on the problems established conventions, it sounds good to me. The current will never actually reach, nor originate, from terminal A because it is an open circuit with infinite resistance.

Quick edit:
The one thing I don't like is that current is, by a more universally established convention, the flow of positive charges. This is because the electrons are going to get a force that moves them to the positive terminal of the potential, the battery. I think the problem means what I said, and is just poorly worded.
 
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atwong713 said:
i say that it is moving away because if i say its positive going into element1 then since its negative its going out of element1 so its moving away from A

Incorrect. The direction of the flow of the electrons is in the same direction as that of the negative current. Here, the negative 2mA is flowing toward A.

Mindscrape said:
Based on the problems established conventions, it sounds good to me. The current will never actually reach, nor originate, from terminal A because it is an open circuit with infinite resistance.

What is wrong with a current flowing through the closed loop V-1-2?

(The points A and B here probably represents parts of the circuit not shown, and not just open -ended wires.)
 
Oh, well if A-B is just a load then the current could go to it. The circuits I was taught often had open terminals with infinite impedance to make what voltages the problem was looking for more apparent.

But yes, I would agree with you that if we are looking at the actual flow of electrons, rather than the flow of positve charges, it would go towards the terminal.