BASIC DC CIRCUIT CALCULATIONSBasic DC TheoryCurrentDivisionSometimes it is necessary to find the individual branch currents in a parallel circuit when onlyresistance and total current are known. When only two branches are involved, the current in onebranch will be some fraction of I_{T}. The resistance in each circuit can be used to divide the totalcurrent into fractional currents in each branch. This process is known as current division.(2-13)I_{1}R_{2}R_{1}R_{2}I_{T}I_{2}R_{1}R_{1}R_{2}I_{T}Note that the equation for each branch current has the opposite R in the numerator. This isbecause each branch current is inversely proportional to the branch resistance.Example: Find branch current for I_{1} and I_{2} for the circuit shown in Figure 30.Figure 30 Current Division Example CircuitES-02 Page 38 Rev. 0

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