Introduction to Electrical Systems

EE 111
Assignment – 1

Q1. Consider the circuit shown in Figure 1. Perform nodal analysis and hence determine
VA, VB, VC. Also determine the power delivered by the current source.

0.2 S
440 V
VC VB
_ + _ + VA
0.15 S
+ 20 V
_ 40 V
0.05 S 0.25 S 25 A

Figure 1

Q2. In the circuit shown in Figure 2, Vs1= -10 V, Is2 = 1 A, and all resistors are 10 Ω.
Apply nodal analysis to determine VA, VB, VC.

3 vx
VB Vc
+ _
VA
+
+
Vs1 vx I s2
_
_

Figure 2

Q3. Consider the circuit shown in Figure 3 along with the defined loops 1, 2 and 3.
Determine I1, I2, I3 and hence determine, v.
1Ω

I2 2Ω
4Ω
I1
2Ω

+ +
14 V 6V
_ _
1Ω

1Ω I3

Figure 3
Q4. Consider the circuit shown in Figure 4, wherein Vs1 = 250 V and Is2 = 0.75 A. Write
two mesh equations and hence determine VB.

100 Ω 300 I x
+ _

Ix 200 Ω 200 Ω

+
+ VB 200 Ω
Vs1 I s2
_ _

Figure 4

Q5. Consider the linear network of Figure 5. Two separate dc measurements are taken. In
the first experiment it is found that when Va = 7 V and Ib = 3 A, the load current is Iload =
3 A. In the second experiment it found that when Va = 7 V and Ib = 1 A, then Iload = 3 A.
Compute Iload when Va = 15 V and Ib = 9 A.
I load
Linear
+ Network
Va _
containing R
dependent
sources

Ib

Figure 5

Q6. Find the Thevenin equivalent circuit of the network shown in Figure 6 as viewed
from A - B

8 kΩ 4 kΩ
A

6 kΩ
+
72 V
_
4 kΩ

54 mA
2kΩ

Figure 6
Q7. Find Thevenin equivalent of the circuit shown in Figure 7 as viewed from A – B.
What is the Norton’s equivalent?

- 2Ix

0.01vx

A
+ 100 Ω
vx
300 Ω 100 Ω

_ 800 Ω
B
Ix

Figure 7

Q8. Find the Norton and Thevenin equivalent of the circuit shown in Figure 8.
4i1
6Ω
+ _
i1

3.0 A 10 Ω

Figure 8

Q9. For the circuit shown in Figure 9, find the load resistance, RL needed for maximum
power transfer. Also determine the maximum power delivered to the load resistor, RL.

400Ω

+
L
0.0015 V

1 k ohm

0.1 A 200 Ω VL RL

Figure 9