DC Network Theorems Unit 5 – Kirchhoff's Solution with 2 Sources
Based on Kirchhoff's current law, the current into NODE 1 (I 1 + I 2 ) must equal the current out
of NODE 1 (I 3 ). Therefore, I 3 = I 1 + I 2.
The currents can now be stated in terms of voltage drops.
I 1 + I 2 = I 3
(VR1 /R1) + (VR2 /R2) = VR3 /R3
Another method of applying Kirchhoff's laws is to implement a solution by using mesh currents.
A mesh is the simplest possible closed path within a circuit.
The following mesh equations are based on this circuit.
FOR MESH 1
(I 1 x R1) + (I 1 x R3) - (I 2 x R3) = VS1
FOR MESH 2
(I 2 x R2) + (I 1 x R3) - (I 2 x R3) = -VS2