(adsbygoogle = window.adsbygoogle || []).push({}); 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 above. Assume that R1 = 1.00kΩ, R2 = 3.00kΩ, R3 = 5.00kΩ, E1 = 75.0V, E2 = 65.0V and E3 = 85.0V.

2. Relevant equations

Kirchhoff's rules

3. The attempt at a solution

Using Kirchhoff's rules I can get I2 = I1 + I3. Which so far is the only thing I'm certain is correct. Next I need two equations from the loops (left and right) and then just solve the system of equations. I don't know if I am setting these up wrong but none of my answers have been correct thus far. I got:

E1 - R1I1 - R2I2 - E2 = 0 and E2 - R2I2 - E2 - I3R3 = 0

which come out to

10 - I1 - 3(I2) = 0 and 20 - 3(I2) - 5(I3) = 0

which results with I1 = 0.869 = 0.000869A when taking into account the resistances were kiloohms. Neither of these answers are correct. Calculations shouldn;t be the problems either because I've been lazy and just plugging into wolfram alpha to solve the systems of equations. I assume I am doing something wrong with equations 2 and 3. Any help would be appreciated.

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# Homework Help: Kirchhoff's Rule and finding current with a system of equations

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