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**1. The problem statement, all variables and given/known data**

Using Kirchhoff's rules, calculate the current in R1 with the directions indicated in the figure below.

http://img11.imageshack.us/img11/6018/sbpic2822.png [Broken]

Assume that R1 = 2.00 kΩ, R2 = 3.00 kΩ, R3 = 4.00 kΩ, E1 = 75.0 V, E2 = 70.0 V and E3 = 85.0 V.

**2. Relevant equations**

Kirchhoff's Rules of voltage loops.

**3. The attempt at a solution**

The problem I'm having is establishing what the voltage loops are here. My book doesn't really explain what to do in the case of multiple batteries and branches...

Here's what I have so far:

I2 = I3 + I1 at the junction points.

Left Loop: E2 - E1 - I1R1 - I2R2 = 0

Right Loop: E2 - E3 - I3R3 - I2R2 = 0

I assumed that since the current goes in the opposite direction on the other side, I change it from counter clockwise on the left to clockwise on the right.

Can anyone please tell me how to properly do this problem? It would be much appreciated. Thanks!

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