Find the unknown currents entering or leaving each node
The currents I_{1} to I_{5} are as follows:
I_{1} = 5.0 A - 2.0 A = 3.0 A
I_{2} = 1.5 A + 2.0 A = 3.5 A
I_{3} = 12.0 A - I_{1} = 12.0 A - 3.0 A = 9.0 A
I_{4} = 1.5 A + I_{3} = 1.5 A + 9.0 A = 10.5 A
I_{5} = 12.0 A - 4.0 A = 8.0 A
Find the value of E
The value of E can be calculated as follows:
E - 4 V - (2 × 10) V - (2 × 20) V + 3 V - (2 × 25) V + 6 V - (2 × 15) V = 0
E = 4 V + 20 V + 40 V - 3 V + 50 V - 6 V + 30 V
E = 135 V