No. |
Question |
1 |
A 50 kW dc shunt motor is loaded to draw rated armature current
at any given speed. When driven
(i) at half the rated speed by armature voltage control and
(ii) at 1.5 times the rated speed by field control, the
respective output powers delivered by the motor are approximately.
|
Options |
A) 25kW in (i) and 75kW in (ii) |
B) 25kW in (i) and 50kW in (ii)
|
C) 50kW in (i) and 75kW in (ii) |
D) 50kW in (i) and 50kW in (ii) |
|
Your Answer |
(Not
Answered) |
Correct Answer |
B |
|
2 |
A fair coin is tossed three times in
succession. If the first toss poduces a head, then the probability
of getting exactly two heads in three tosses is |
Options |
|
Your Answer |
(Not
Answered) |
Correct Answer |
D |
|
3 |
In the matrix equation Px = q, which of the
following is a necessary condition for the existence of at least one
solution for the unknown vector x:
|
Options |
A) Augmented matrix [Pq] must have the same rank as
matrix P
|
B) Vector q must have only non-zero elements
|
C) Matrix P must be singular
|
D) Matrix P must be square |
|
Your Answer |
(Not
Answered) |
Correct Answer |
A |
|
4 |
At an industrial sub-station with a 4 MW load,
a capacitor of 2 MVAR is installed to maintain the load power factor
at 0.97 lagging. If the capacitor goes out of serivce, the load
power factor becomes |
Options |
A) 0.85 |
B) 1.00
|
C) 0.80 lag |
D) 0.90 lag |
|
Your Answer |
(Not
Answered) |
Correct Answer |
C |
|
5 |
In the GH(s) plane, the
Nyquist plot of the loop transfer function
G(s)H(s) =
asses through the negative real axis at the point
|
Options |
A) (-0.25, j0) |
B) (-0.5, j0)
|
C) (-l, j0) |
D) (-2, j0) |
|
Your Answer |
(Not
Answered) |
Correct Answer |
B |
|
6 |
If S =
ò |
¥ |
|
x-3 dx, then S has the value |
1 |
|
|
Options |
|
Your Answer |
(Not
Answered) |
Correct Answer |
C |
|
7 |
The following motor definitely has a permanent
magnet rotor |
Options |
A) DC commutator motor |
B) Brushless dc motor
|
C) Stepper motor |
D) Reluctance motor |
|
Your Answer |
(Not
Answered) |
Correct Answer |
C |
|
8 |
The conduction loss versus device current
characteristic of a power MOSFET is best approximated by |
Options |
A) a parabola
|
B) a straight line
|
C) a rectangular hyperbola
|
D) an exponentially decaying function |
|
Your Answer |
(Not
Answered) |
Correct Answer |
A |
|
9 |
A digital-to-analog converter with a full-scale
output voltage of 3.5 V has a resolution close to 14m V. Its bit
size is |
Options |
|
Your Answer |
(Not
Answered) |
Correct Answer |
B |
|
10 |
A 50 Hz, bar primary CT has a secondary with
500 turns. The secondary supplies 5 A current into a purely
resistive burden of l W. The magnetizing ampere-turns is 200. The
phase angle between the primary and secondary current is |
Options |
A) 4.6°
|
B) 85.4° |
C) 94.6°
|
D) 175.4° |
|
Your Answer |
(Not
Answered) |
Correct Answer |
A |
|
11 |
The armature resistance of a permanent magnet
dc motor is 0.8 W. At no load, the motor draws 1.5 A from a supply
voltage of 25 V and runs at 1500 rpm. The efficiency of the motor
while it is operating on load at 1500 rpm drawing a current of 3.5 A
from the same source will be |
Options |
A) 48.0% |
B) 57.1%
|
C) 59.2% |
D) 88.8% |
|
Your Answer |
(Not
Answered) |
Correct Answer |
A |
|
12 |
A bipolar junction transistor (BJT) is used as
a power control switch by biasing it in the cut-off region (OFF
state) or in the saturation region (ON state). In the ON state, for
the BJT |
Options |
A) both the base-emitter and base-collector
junctions are reverse biased |
B) the base-emitter junction is reverse biased, and
the base-collector junction is forward biased |
C)
the base-emitter junction is forward biased, and the
base-collector junction is reverse biased
|
D) both the base-emitter and base-collector
junctions are forward biased |
|
Your Answer |
(Not
Answered) |
Correct Answer |
D |
|
13 |
For the equation,
s3 - 4s2+ s + 6 = 0
the number of roots in the left half of s-plane will be |
Options |
A) zero |
B) one
|
C) two |
D) three
|
|
Your Answer |
(Not
Answered) |
Correct Answer |
C |
|
14 |
The Q - meter works on the principle of |
Options |
A) mutual inductance |
B) self inductance
|
C) series resonance |
D) parallel resonance |
|
Your Answer |
(Not
Answered) |
Correct Answer |
C |
|
15 |
A 800 kV transmission line is having per phase
line inductance of 1.1 mH/km and per phase line capacitance of 11.68
nF/km. Ignoring the length of the line, its ideal power transfer
capability in MW is |
Options |
A) 1204 MW |
B) 1504 MW |
C) 2085 MW |
D) 2606 MW |
|
Your Answer |
(Not
Answered) |
Correct Answer |
C |
|
16 |
The insulation strength of an EHV transmission
line is mainly governed by |
Options |
A) load power factor |
B) switching over-voltages
|
C) harmonics |
D) corona |
|
Your Answer |
(Not
Answered) |
Correct Answer |
B |
|
17 |
If the following program is executed in a icroprocessor, the
number of instruction cycles it will take from START to HALT is
START MVI A, 14H ; Move 14H to register A
SHIFT RLC
; Rotate left without carry
JNZ
SHIFT ; Jump on non-zero to SHIFT
HALT |
|
Options |
|
Your Answer |
(Not
Answered) |
Correct Answer |
C |
|
18 |
A moving iron ammeter produces a full scale
torque of 240 mNm with a deflection of
120° at a current of 10 A. The rate of change of self inductance (mH/radian)
of the instrument at full scale is |
Options |
A) 2.0 mH/radian |
B) 4.8 mH/radian |
C) 12.0 mH/radian |
D) 114.6 mH/radian |
|
Your Answer |
(Not
Answered) |
Correct Answer |
B |
|
19 |
The output voltage waveform of a three-phase
square-wave inverter contains |
Options |
A) only even harmonics |
B) both odd and even harmonics |
C) only odd harmonics |
D) only triplen harmonics
|
|
Your Answer |
(Not
Answered) |
Correct Answer |
C |
|
20 |
If P and Q are two random events, then the
following is TRUE
|
Options |
A) Independence of P and Q implies that probability
(P Q
) = 0
|
B) Probability (P
Q )
Probability (P) + Probability (Q)
|
C) If P and Q are mutually exclusive, then they
must be independent
|
D) Probability (P
Q )
Probability (P)
|
|
Your Answer |
(Not
Answered) |
Correct Answer |
D |