Answers to Problems - The Current Divider


  1. In the circuit illustrated below, two resistors are in parallel with a 120 V supply voltage. If the resistance values of R1 and R2 are 56 Ω and 100 Ω respectively, find the current flowing through each resistor (I1 and I2), the total current flowing through the circuit (IT), and the total circuit resistance (RT).

    A potential divider consisting of two resistors in series with a supply voltage

    A potential divider consisting of two resistors in series with a supply voltage



    I1  =  120 V  =  2.143 A   (Ohm's law)
    56 Ω

    I2  =  120 V  =  1.2 A   (Ohm's law)
    100 Ω

    IT  =  2.143 A  +  1.2 A  =  3.343 A   (Kirchhoff's current law)


    RT  =  120 V  =  35.896 Ω   (Ohm's law)
    3.343 A

  2. In the circuit illustrated below, three resistors are in parallel with a 24 V supply voltage. If the resistance values of R1, R2 and R3 are 15 Ω, 20 Ω and 10 Ω respectively, find the current flowing through each resistor (I1, I2 and I3), the total current flowing through the circuit (IT), and the total circuit resistance (RT).

    A potential divider consisting of two resistors in series with a supply voltage

    A potential divider consisting of two resistors in series with a supply voltage



    I1  =  24 V  =  1.6 A   (Ohm's law)
    15 Ω

    I2  =  24 V  =  1.2 A   (Ohm's law)
    20 Ω

    I3  =  24 V  =  2.4 A   (Ohm's law)
    10 Ω

    IT  =  1.6 A  +  1.2 A  +  2.4 A  =  5.2 A   (Kirchhoff's current law)


    RT  =  24 V  =  4.615 Ω   (Ohm's law)
    5.2 A