Solve Kirchoff's Laws Homework with Expert Help

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The discussion focuses on solving a homework problem related to Kirchhoff's Laws, specifically involving three loops and two nodes in a circuit. A participant is confused about calculating the total resistance for one loop and mistakenly sums it to 2.5 ohms, leading to an incorrect current calculation. It is clarified that the sum of potential changes in a closed loop must equal zero and that only two loops and one node need to be considered for the analysis. Additionally, it is emphasized that the current value will vary across different parts of the circuit. Understanding these principles is crucial for correctly applying Kirchhoff's Laws to solve the problem.
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Homework Statement


http://img87.imageshack.us/img87/5418/kirchoff2nr2.jpg

Now, I dnt have a clue on homework to solve this.
 
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Why? What is confusing you?
 
there are three loops and 2 nodes.

See when considering one loop, do I have to add all the resistance together.
So for loop 1 (1v)

the resistance is 2.5

so current = 1/2.5=0.4 A

but I am getting the wrong answer
 
How did you get 2.5? You must sum the entire loop. The sum of the changes in potential across all the elements in a closed loop must be zero. You only need to consider two loops here, and the one node (which gives you the relation between the three branch currents). The value for I won't be the same in each part of the circuit.
 
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