Biomedical Engineering Reference
In-Depth Information
EXAMPLE PROBLEM 9.9
Find the voltage across the 5 A current source,
V
5
, in the following figure using superposition.
3V
0
3
Ω
5
Ω
+
+
+
−
10V
2
Ω
5 A
V
0
V
5
−
−
Solution
First consider finding the response,
V
0
10
, due to the 10 V source only, with the 5 A source dead,
as shown in the following figure. As required during the analysis, the dependent current source is
kept in the modified circuit and should not be set dead.
3V
0
10
I = 0 A
3
Ω
A
+
+
5
Ω
3V
0
10
+
−
10 V
2
Ω
V
0
10
V
5
10
-
-
Notice that no current flows through the open circuit created by the dead current source and
that the current flowing through the 5
O
resistor is 3
V
0
. Therefore, applying KCL at node A gives
V
0
10
10
þ
V
0
10
2
þ
3
V
3
V
¼
0
0
10
0
10
3
which gives
V
0
10
¼
4V. KVL gives
V
0
10
5
3
V
0
10
þ
V
5
10
¼
0, and therefore
V
5
10
¼
64 V
:
