Problem 2.24 Given that in the circuit of Fig. P2.24, I1 = 4 A, I2 = 1 A, and I3 =
1 A, determine node voltages V1 , V2 , and V3 .
I2
I1
1 Ω V1
R1 = 18 Ω
6Ω
+
40 V _
V2
6Ω
V3
6Ω
18 Ω
I3
Figure P2.24: Circuit of Problem 2.24.
Solution:
R1 = 18 Ω
1 Ω V1
I4
6 Ω V2
+
40 V _
6Ω
6Ω
V3
18 Ω
Fig. P2.24 (a)
V1 = 40 − (1 Ω) × I1 = 40 − 4 = 36 V.
KCL at node V1 leads to
I4 = I1 − I2 = 4 − 1 = 3 A.
Hence,
V2 = V1 + 6I4 = 36 − 6 × 3 = 18 V.
The voltage across R1 is 18I2 .
Hence,
V3 = V1 − 18I2 = 36 − 18 × 1 = 18 V.
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