Legal Metrology • Electrical Engineering Paper-II
The value of A, B, C and D constants for a short transmission line are respectively
A)
0, 1, 1 and 1
B)
Z, 0, 1 and 1
C)
1, Z, 0 and 1
D)
1, 1, Z and 0
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is '1, 1, Z and 0' (Option D).
Legal Metrology • Electrical Engineering Paper-II
Consider the following quantities: 1. Real power, 2. Reactive power, 3. Power factor, 4. Input current, 5. Bus voltage magnitude, 6. Bus voltage phase angle. For the purpose of the load flow studies of a power system, each bus or node is associated with which one of the combinations of the above four quantities?
A)
1, 3, 4 and 5
B)
1, 2, 3 and 4
C)
1, 2, 5 and 6
D)
2, 3, 5 and 6
Load-flow buses are characterized by combinations of P, Q, |V| and angle δ; the listed combination is 1,2,5,6.
Legal Metrology • Electrical Engineering Paper-II
Of the following statements concerning parallel operation of transformers, the one which is not correct is
A)
transformers must have equal KVA ratings
B)
transformers must have equal voltage ratings
C)
transformers must have same ratio of transformation
D)
transformers must be operated at the same frequency
Parallel transformers need compatible ratings, voltage ratios, impedance, polarity, and frequency; identical kVA rating is not mandatory, so A is not correct.
Legal Metrology • Electrical Engineering Paper-II
Ferranti effect on long overhead lines is expressed when it is
A)
lightly loaded
B)
fully loaded at unity p.f
C)
fully loaded at 0.8 p.f lag
D)
none of the above
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is 'fully loaded at 0.8 p.f lag' (Option C).
Legal Metrology • Electrical Engineering Paper-II
Given the transfer function G(s) = 1 / (s^2 + 13.2s + 121) of a system. Which of the following characteristics does it have?
A)
overdamped and settling time 1.1s
B)
critically damped and settling time 0.8s
C)
under-damped and settling time 0.6s
D)
under-damped and settling time 0.707s
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is 'overdamped and settling time 1.1s' (Option A).
Legal Metrology • Electrical Engineering Paper-II
If the poles of a system lie on the imaginary axis, the system will be
A)
conditionally stable
B)
stable
C)
unstable
D)
marginally stable
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is 'unstable' (Option C).
Legal Metrology • Electrical Engineering Paper-II
Which of the following relay structure produce torque more efficiently?
A)
induction cup structure
B)
watt-hour meter structure
C)
shaded pole structure
D)
none of these
An induction-cup relay produces comparatively high torque for its size and is efficient in operation.
Legal Metrology • Electrical Engineering Paper-II
Lap winding is suitable for
A)
high current, low voltage d.c generators
B)
high current, high voltage d.c generators
C)
low current, low voltage d.c generators
D)
low current, high voltage d.c generators
Lap windings provide many parallel paths, making them suitable for high-current, low-voltage DC machines.
Legal Metrology • Electrical Engineering Paper-II
An autotransformer having a transformation ratio of 0.8 supplies a load of 3kW. The power transferred conductively from primary to secondary is
A)
0.4kW
B)
1.5kW
C)
2.4kW
D)
0.27kW
For the autotransformer relation used in the source, the conducted portion is 0.8×3=2.4 kW.
Legal Metrology • Electrical Engineering Paper-II
The phase lead compensator Gc(s) = [10(1 + 0.3s)] / [15s] would provide a maximum phase shift of
A)
45°
B)
30°
C)
60°
D)
20°
Based on established principles in Electrical / Electronics Engineering, the correct and most clinically/technically appropriate choice is '45°' (Option A).
Legal Metrology • Electrical Engineering Paper-II
The frequency at which the magnitude of the Bode plot crosses 0dB axis is termed as
A)
natural frequency
B)
phase crossover frequency
C)
corner frequency
D)
gain crossover frequency
Based on established principles in Electrical / Electronics Engineering, the correct and most clinically/technically appropriate choice is 'gain crossover frequency' (Option D).
Legal Metrology • Electrical Engineering Paper-II
The greater the diversity factor of a power station
A)
Indicates higher plant capacity
B)
higher is the cost of generation of power
C)
lesser is the cost of generation of power
D)
none of the above
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is 'none of the above' (Option D).
Legal Metrology • Electrical Engineering Paper-II
The transfer function of a P-I controller is
A)
K + K_i/s
B)
K + K_i*s
C)
K_i/s + K_d*s
D)
K_i*s - K
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is 'K + K_i/s' (Option A).
Legal Metrology • Electrical Engineering Paper-II
If field resistance of a d.c shunt generator is increased beyond its critical value, the generator
A)
will not build up
B)
output voltage will exceed its name plate rating
C)
may burn out if loaded to its name plate rating
D)
power output may exceed its name plate rating
If field resistance exceeds critical resistance, the shunt generator cannot build up voltage.
Legal Metrology • Electrical Engineering Paper-II
In a transmission line, the generalised circuit constants of the transmission line AD-BC is equal to
A)
zero
B)
1
C)
-1
D)
0.5
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is 'zero' (Option A).
Legal Metrology • Electrical Engineering Paper-II
Regenerative braking in d.c shunt motor is used when
A)
load has overhauling characteristics
B)
quick motor reversal is required
C)
controlling elevators, rolling mills
D)
none of the above
Regenerative braking is especially useful with overhauling loads, where the load drives the motor.
Legal Metrology • Electrical Engineering Paper-II
Consider the given block diagram. The overall transfer function is [Block Diagram Image Missing]
A)
14G1G2 + G3G4 + G5G6G7 + G8G9G10
B)
14G1G2 + G3G4 + G5G6G7 + G8G9G10G11
C)
14G1G2 + G3G4 + G5G6G7 + G8G9G10G11G12
D)
12G1G2 - G3G4 + G5G6G7 + G8G9G10G11G12
Based on established principles in Electrical / Electronics Engineering, the correct and most clinically/technically appropriate choice is '14G1G2 + G3G4 + G5G6G7 + G8G9G10' (Option A).
Legal Metrology • Electrical Engineering Paper-I
Fermi level in a p-type semiconductor lies close to
A)
The top of the valance band
B)
The bottom of the valence band
C)
The top of the conduction band
D)
The bottom of the conduction band
In a p-type semiconductor, the Fermi level shifts toward the valence band.
Legal Metrology • Electrical Engineering Paper-I
What is the value of total electric flux coming out of a closed surface?
A)
Zero
B)
Equal to volume charge density
C)
Equal to the total charge enclosed by the surface
D)
Equal to the surface charge density
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is 'Zero' (Option A).
Legal Metrology • Electrical Engineering Paper-I
If A and J are the vector potential and current density vectors associated with a coil, then ∫A·J dV has the units of
A)
Flux-linkage
B)
Power
C)
Energy
D)
Inductance
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is 'Power' (Option B).
Legal Metrology • Electrical Engineering Paper-I
The phase velocity of waves propagating in a hollow metal waveguide is
A)
greater than the velocity of light in free space
B)
less than the velocity of light in free space
C)
equal to the velocity of light in free space
D)
equal to the group velocity
Waveguide phase velocity is greater than c, while group velocity is less than c.
Legal Metrology • Electrical Engineering Paper-I
The electric field strength at any point equals
A)
The potential gradient at that point
B)
Negative of the potential gradient at that point
C)
The charge at that point
D)
Negative of the charge at that point
Electric field strength is the negative gradient of the electric potential (E = -∇V).
Legal Metrology • Electrical Engineering Paper-I
In a uniform plane wave, E and H are related as below
A)
E = Z H
B)
E = H / Z
C)
E = Z^2 H
D)
E = H / Z^2
Based on established principles in Electrical / Electronics Engineering, the correct and most clinically/technically appropriate choice is 'E = H / Z' (Option B).
Legal Metrology • Electrical Engineering Paper-I
For a two-port network to be reciprocal, it is necessary that
A)
Z12=Z21 and Y12=Y21
B)
z11=z22 and AD-BC=0
C)
h12=-h21 and AD-BC=0
D)
y12=Y21 and h12=-h21
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is 'z11=z22 and AD-BC=0' (Option B).
Legal Metrology • Electrical Engineering Paper-I
In the given circuit, maximum transfer to load ZL takes place when ZL equals
A)
(4+j5)Ω
B)
(4-j5)Ω
C)
(5 +j4)Ω
D)
(5-j4)Ω
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is '(4+j5)Ω' (Option A).
