**2014**

1.
For maximum power transfer between two cascaded sections of an
electrical network, the relationship between the output impedance Z

_{1}of the first section to the input impedance Z_{2}of the second section is
a)
Z

_{2}= Z_{1}
b)
Z

_{2}= – Z_{1}
c)
Z

_{2}= Z_{1}^{*}
d)
Z

_{2}= – Z_{1}^{*}
2.
Consider the configuration shown in the figure, which is a portion
of a larger electrical network. For R = 1 Ω
and
currents i

_{1}= 2A, i_{4}= – 1A, i_{5}= – 4A, which one of the follwoing is TRUE?
a)
i

_{6}= 5 A
b)
i

_{3}= – 4 A
c)
Data
is sufficient to conclude that the supposed currents are impossible

d)
Data
is insufficient to identify the currents i

_{2}, i_{3}and i_{6}
3.
A Y– network has resistances of 10 Ω
each
in two of its arms, while the third arm has a resistance of 11 Ω.
In
the equivalent Δ
– network,
the lowest value (in Ω)
among the three resistances is _________

4.
A 230 volts rms source supplies power to two loads connected in
parallel. The first load draws 10kW at 0.8 leading power factor and
the second one draws 10 kVA at 0.8 lagging power factor. The complex
power delivered by the source is

a)
(18
+ j 1.5) kVA

b)
(18
–
j 1.5) kVA

c)
(20
+ j 1.5) kVA

d)
(20
–
j 1.5) kVA

5.
A
periodic variable x is shown in the figure as a function of time.

The
root-mean-square (rms) value of x is _________________
6.
In the circuit shown in the figure, the value of capacitor C (in mF)
needed to have critically damped response i(t) is
____________________

7.
Norton's theorem states that a complex network connected to a load
can be replaced with an equivalence impedance

a)
in
series with a current source

b)
in parallel with a voltage source

c)
in
series with a voltage source

d)
in
parallel with a current source

8.
In the figure shown, the ideal switch has been open for a long time.

If it is closed at t = 0, then the magnitude of the current (in mA)
through the 4 kΩ
resistor
at t = 0^{+}is ____________

9.
A series LCR circuit is operated at a frequency different from its
resonant frequency. The operating frequency is such that the current
leads the supply voltage. The magnitude of current is half the value
at resonance. If the values of L, C and R are 1H, 1F and 1Ω
respectively,
then the opeating angular frequency (in rad/sec) is
____________________

10.
In the h – parameter model of 2 – port network given in the
figure shown,

the value of h_{22}(in siemens) is _____________

11.
In the figure shown, the capacitor is initially uncharged.

Which one
of the following expressions describes the current I(t) in mA for t >
0 ?
12.
In the magnetically coupled circuit shown in the figure, 56% of the
total flus emanating from one coil links the other coil.

The value of
the mutual inductance (in H) is _________________
13.
A series RC circuit is connected to a DC voltage source at time t =
0. The relation between the source voltage V

_{S}, the resistance R, the capacitance C and the current i(t) is given below. Which one of the following represents the current i(t) ?
14.
In the figure shown, the value of the current I (in Amperes) is
______________

15.
Consider the building block called 'Network N' shown in the figure.
Let C = 100 µF
and R = 10 kΩ.

Two
such blocks are connected in cascade, as shown in the figure,

find
the transfer function V_{3}(s)/V

_{1}(s) of the cascaded network is

16.
In the circuit shown in the figure, the value of node voltage V

_{2}(in volts) is
a)
22
+ j 2

b)
2
+ j 22

c)
22
– j 2

d)
2
– j 22

17.
In the circuit shown in the figure, the angular frequency ω (in
rad/sec), at which the Norton equivalent impedance as seen from
terminals b – b' is purely resistive, is _____________

18.
For the Y – network shown in the figure, the value of R

_{1}(in Ω) in the equivalent Δ – network is ____
19.
The circuit shown in the figure represents a

a)
Voltage
controlled voltage source

b)
voltage
controlled current source

c)
current
controlled current source

d)
current
controlled voltage source

20.
The magnitude of current (in mA) through the resistor R

_{2}in the figure shown is ___________
21.
The steady state output of the circuit shown in the figure is given
by y(t) = A(ω) sin(ωt + φ(ω)).

If the amplitude |A(ω)| = 0.25,
then the frequency ω is
22.
In the circuit shown in the figure,

the value of V_{o}(t) (in volts) for t → ∞ is ___________

23.
The equivalent resistance in the infinite ladder network shown in
the figure is R

The value of R_{e}._{e}/R is ________________

24.
For the two – port network shown in the figure, the impedance (Z)
matrix (in Ω)
is