**2013**

1.
Consider a delta connection of resistors and its equivalent star
connection as shown below.

If all elements of the delta connection
are scaled by a factor k, k > 0, the elements of the corresponding
star equivalent will be scaled by a factor of
a)
k

^{2}
b)
k

c)
1/k

d)
√k

2.
The transfer function V

_{2}(s)/V_{1}(s) of the circuit shown below is
3.
A source V

_{s}(t) = V cos100πt has an internal impedance of (4 + j3) Ω. If a purely resistive load connected to this source has to extract the maximum power out of the source, its value in Ω should be
a)
3

b)
4

c)
5

d)
7

4.
In the circuit shown below, if the source voltage V

_{s}= 100∟53.13^{o}volts then the thevenin's equivalent voltage in volts as seen by the load resistance R_{L}is
5.
The following arrangement consists of an ideal transformer and an
attenuator which attenuates by a factor of 0.8. An ac voltage V

_{WX1}= 100 volts is applied across WX to get an open circuit voltage V_{YZ1}across YZ. Next, an ac voltage V_{YZ2}= 100 volts is applied across YZ to get an open circuit voltage V_{WX2}across WX. Then V_{YZ1}/V_{WX1}, V_{WX2}/V_{YZ2}are respectively
6.
Two magnetically uncoupled inductive coils have Q factors q

_{1}and q_{2}at the chosen operating frequency. Their respective resistances are R_{1}and R_{2}. When connected in series, their effective Q factor at the same operating frequency is
a)
q

_{1}+ q_{2}
b)
(1/q

_{1}) + (1/q_{2})
c)
(q

_{1}R_{1}+ q_{2}R_{2}) / (R_{1}+ R_{2})
d)
(q

_{1}R_{2}+ q_{2}R_{1}) / (R_{1}+ R_{2})
7.
Three capacitors C

For the interconnection
shown below, the maximum safe voltage in volts that can be applied
across the combination, and the corresponding total charge in µC
stored in the effective capacitance across the terminals are
respectively._{1}, C_{2}and C_{3}whose values are 10 µF, 5 µF and 2 µF respectively, have breakdown voltages of 10, 5 and 2 volts respectively.
a)
2.8 and 3.6

b)
7
and 119

c)
2.8
and 36

d)
7 and 80

**Common Data for Questions 8 and 9:**

consider
the figure shown below

8.
The current I

_{S}in Amps in the voltage source, and the voltage V_{S}in volts across the current source respectively are
a)
13,
- 20

b)
8,
- 10

c)
- 8,
20

d)
- 13, 20

9. The current in the 1 Ω resistor in Amps is

a)
2

b)
3.33

c)
10

d)
12