Kirchoff's Laws Problem - Power

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The discussion revolves around calculating the rate of electrical energy conversion to internal energy in two resistors using Kirchhoff's Laws. The user has defined current directions and set up equations based on the junction and loop rules but is struggling to obtain consistent results with their homework. They calculated currents I1, I2, and I3 but found discrepancies when applying the power formula P=I^2*R. A suggestion was made to ensure that the chosen current directions are consistently applied in the equations, and an alternative nodal analysis approach was recommended for clarity. The conversation highlights the importance of maintaining consistent assumptions in circuit analysis to achieve accurate results.
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Homework Statement


At what rate is electrical energy converted to internal energy in the 4.56Ω and the 5.91Ω resistors in the figure?

Homework Equations


Kirchoff's Laws:
ƩI(in) = ƩI(out) Junction Rule

ƩΔV = 0 Loop Rule


The Attempt at a Solution


I have set the top branch current to go from right to left = I(3)
I have set the middle branch current to go from right to left = I(2)
I have set the bottom branch current to go from left to right = I(1)

The left middle junction results in the following I(3) + I(2) = I(1)...Junction#1
Loop #1 = 0 = 6.96V-5.91I(2)-4.56I(3)
Loop #2 = 0 = -9.56I(1)-5.91I(2)+1.86V

I get I1=2.7502
I2=-4.1340
I3=6.8842

The answers I get when using the P=I^(2)*R...do not yield results consistent with the online homework

I have tried this several different ways and the answer according to my homework do not match. Please provide some insight here.

Thank You.
 

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I think you're not following your own stipulations for current directions. Once you choose them, if you start writing equations you need to follow through.

When you "pass though" a resistor in the direction of the assumed current flow, you expect a voltage drop. If you pass through against the flow then you get a voltage rise.

Just a thought: you might find a nodal analysis approach to be easy to apply here.
 
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