Fundamental Electrical and Electronic Principles, Third Edition

58 Fundamental Electrical and Electronic PrinciplesADCA :103I21( I2I3)3I2I2I3104II……………[ 3]2 3Multiplying equation [1] by 2, equation [2] by 3 and then adding them0 12I16I210I3……………[] 1 2012I13I230I3……………[ 2]30 3I40I 3 ……………[ 4]2Multiplying equation [3] by 3, equation [4] by 4 and then adding them30 12I2 3I3……………[ 3]3012I160I……………[ 4]42 330 163I330I3 0.184A Ans163Substituting for I 3 in equation [3]104I20.1844I2 9.81698 . 16I2 2. 454 A Ans4Substituting for I 3 and I 2 in equation [2]0 4I12. 454 1.844I1 4.2944.294I1 1. 074 A Ans4I I1I21. 0742.454I 3. 529 A AnsSince all of the answers obtained are positive values then the currents willflow in the directions marked on the circuit diagram.Worked Example 2.12Q If the circuit of Fig. 2.24 is now amended by simply changing the value of R DC from 1 Ω to 2 Ω , calculatethe current flowing through the 5 Ω resistor in the central limb.AThe amended circuit diagram is shown in Fig. 2.25 .ABDA :06I15I33I206I 3I 5I……………[ ]1 2 31