DC CIRCUIT ANALYSISBasic DC TheoryFigure 42 Applying Current Law to JunctionThe sum of the currents out of the junction is:0.2686 + 0.0772 = 0.3458 a= 345.8 maThe current into the junction is 345.8 ma.The current into the junction is equal to the current out of the junction. Therefore, the solutionchecks.NodeEquationsKirchhoff’s current law, as previously stated, says that at any junction point in a circuit thecurrent arriving is equal to the current leaving. Let us consider five currents entering and leavinga junction shown as P (Figure 43). This junction is also considered a node.Assume that all currents entering the node are positive, and all currents that leave the node arenegative. Therefore, I_{1}, I_{3}, and I_{4} are positive, and I_{2} and I_{5} are negative. Kirchhoff’s Law alsostates that the sum of all the currents meeting at the node is zero. For Figure 43, Equation(2-19) represents this law mathematically.I_{1} + I_{2} + I_{3} + I_{4} + I_{5} = 0 (2-19)ES-02 Page 54 Rev. 0

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