1.What are independent and dependent sources?
An ideal independent source is an active element that provides a specified voltage or
current that is completely independent of other circuit elements, present in the circuit.
An ideal dependent source is an active element in which the source quantity is
controlled by voltage across (or) current through any of the element present in the
circuit.
2. State source transformation technique.
A source transformation is the process of replacing a voltage source VS in series with a
resistor ‘R’ by a current source Is in parallel with a resistor ‘R’ or vice versa.
3.A 9V battery can supply 12 A for a parallel set of Christmas tree lights. If each light is
15 Ω, Calculate the maximum number of bulbs that can be connected.
R1  R2  ....Rn  15 
Req 
V
9

 0.75 
I 12
Req 
1
1
1
n

 .... 
R1 R2
Rn R
1
n
15

n
 20
0.75 R
0.75
The maximum number of bulbs that can be connected in parallel is = 20
4. State Ohm’s laws.
Ohm's law states that the potential drop across a resistor is directly proportional to the
current ‘ i ’ flowing through the resistor at constant temperature.
i.e.,
V i
or
V  Ri
Where ‘R’ is the proportionality constant
5. What are active and passive elements?
An active element is capable of generating energy while a passive element is not
capable of generating energy.
6. Convert given delta network with resistance value of 6Ω each into a star network.
R1  R2  R3 
66
2
666
7. State Norton’s theorem
Any linear active network with output terminals AB can be replaced by a single current source
I SC in parallel with single impedance Z th as shown in Fig….
I SC is the current through the short circuit applied to the terminals of the active network. The
shunt impedance Z th is the looking back impedance at the terminals AB, when all internal
sources are set equal to zero.
8. Calculate Thevenin impedance at terminals a-b in Fig.
Solution: The 5 volt source is short circuited and the equivalent circuit is shown in Fig below.
Zth 
1   j   j 
1 j
1
1 j
o
 0.70745 
9. State Millman’s theorem.
Any electrical network with ‘n’ voltage sources namely V1 ,V2 ,....Vn with internal resistances
R1 , R2 ,....Rn connected in parallel can be replaced by a single voltage source V in series with R
by Millman’s theorem.
10.List the applications of Thevenin’s theorem.
 It is applied to all linear circuits, including electronic circuits represented by the
controlled sources.
 It is useful when it is desired to know the effect of the response in the network.

11. State reciprocity theorem
The reciprocity theorem states that in a linear, bilateral single source network the ratio of
excitation (input) to response (output) is constant when the positions of excitation and response
are interchanged.
12.Calculate the value of IN for the circuit shown in Fig.
IN 
V 12

 0.1Amps.
R 120
13.Find the current flowing through R=5  resistor for the circuit shown in Fig using
Superposition principle.
Open circuiting 2Amps current source, i' 
Short circuiting 10Volt voltage source, i " 
10
 1 Amps
10
25
 1 Amps
10
The current flowing through R=5  resistor is,
i  i '  i''  0 Amps
14.At what condition maximum power transfers load?
Maximum power transfer to the load occurs when it has a value equal to the resistance of the
network looking back at it from the load terminals.
15. Define distributed elements. Give an example.
A distributed element is a one which cannot be physically separated for electrical
purpose.
Example: Transmission line, Coaxial cable.
16. Determine ‘V’ in the circuit shown in Fig.below.
10  2
 2Volts
RT  5  5  10  and V 
10
17.Determine the current I3 in the circuit shown in Fig.below
RT  4  6  2  12 
I1 
24
 2 Amps
12
18.
Find
I
I2 
the
100  40
 1.5 Amps
40
28
 1 Amps
16
current
I3 
i
1 6
 0.5 Amps
12
and
voltage
across
30
in
Fig.below
19.Give the algorithmic steps of Mesh current analysis.
Given a circuit with ‘n’ meshes, the mesh analysis of the circuit involves the
following three steps for finding mesh currents.
 Mesh currents
i1 , i2 ,..... in
are assigned to ‘n’ meshes.
 KVL is applied to each of the ‘n’ meshes. Ohm’s law is used to express he
voltages in terms of the mesh currents.
 The resulting ‘n’ simultaneous equations are solved to obtain the unknown mesh
currents.
20. Find the voltage between A and B in the network shown in Fig
Vab  100 
9000
 90Volts
10000