Legal Metrology • Paper-I
The electric field of a uniform plane wave is given by E = 10sin(10wt-πz)ax + 10cos(wt-πz)ay (V/m). The polarization of the wave is
A)
Circular
B)
Elliptical
C)
Linear
D)
Undefined
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is 'Undefined' (Option D).
Legal Metrology • Paper-I
When network are connected in series, it is convenient to use
A)
Z-parameter
B)
Y-parameter
C)
h-parameter
D)
g-parameter
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is 'Y-parameter' (Option B).
Legal Metrology • Paper-I
The important postulate arising out of Maxwell’s modification of Ampere’s law is that
A)
a steady current produces a magnetic field
B)
a changing magnetic field produces an electric field
C)
a changing electric field produces a magnetic field
D)
a motional emf is produced by a coil moving in a magnetic field
Based on established principles in the relevant subject area, the correct and most appropriate choice is 'a changing magnetic field produces an electric field' (Option B).
Legal Metrology • Paper-I
Which one of the following digital voltmeters is most suitable to eliminate the effect of period noise?
A)
Ramp type digital voltmeter
B)
Integrating type digital voltmeter
C)
Successive approximation type digital voltmeter
D)
Servo type digital voltmeter
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is 'Servo type digital voltmeter' (Option D).
Legal Metrology • Paper-I
In a series RLC circuit, the maximum voltage across the capacitor occurs at a frequency
A)
double the resonant frequency
B)
equal to resonant frequency
C)
times the resonant frequency
D)
below the resonant frequency
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is 'below the resonant frequency' (Option D).
Legal Metrology • Paper-I
The electron relaxation time of metal A is 2.7×10-4 sec and that of B is 1.35×10-4 sec. The ratio of resistivity of B to resistivity of A will be
A)
4.0
B)
2.0
C)
0.5
D)
0.25
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is '2.0' (Option B).
Legal Metrology • Paper-I
A successive approximation A/D converter has a resolution of 20 mV. What is its digital output for an analog input of 2.17V?
A)
01101100
B)
01101101
C)
01101011
D)
01110100
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is '01101100' (Option A).
Legal Metrology • Paper-I
The moving coil in a dynamometer wattmeter is connected
A)
in series with the fixed coil
B)
across the supply
C)
in series with the load
D)
across the load
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is 'across the load' (Option D).
Legal Metrology • Paper-I
Which of the following is incorrect with regard to reciprocity theorem.
A)
applicable for single voltage source
B)
initial conditions are assumed to be zero
C)
there should not be any extra dependent or independent sources in network
D)
none of these
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is 'none of these' (Option D).
Legal Metrology • Paper-I
For an ideal step-down (n:1) transformer, which one of the following is the ABCD parameter matrix?
A)
[[n, 1], [1, n]]
B)
[[n, 0], [0, n]]
C)
[[1, 0], [n, 1/n]]
D)
[[n, 0], [1, 1/n]]
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is '[[1, 0], [n, 1/n]]' (Option C).
Legal Metrology • Paper-I
Measurement of flow, thermal conductivity and liquid level using thermistors make use of
A)
resistance decrease with temperature
B)
resistance increase with temperature
C)
self-heating phenomenon
D)
change of resistivity
Correct option: C — self-heating phenomenon. This matches the standard definition/result for the stated question.
Legal Metrology • Paper-I
For an electromagnetic wave incident from one medium on to a second medium, total reflection takes place when the angle of incidence is equal to the
A)
Brewster angle with E field perpendicular to the plane of incidence
B)
Brewster angle with E field parallel to the plane of incidence
C)
Critical angle with the wave moving from the denser medium to a rarer medium
D)
Critical angle with the wave moving from the a rarer medium to a denser medium
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is 'Brewster angle with E field perpendicular to the plane of incidence' (Option A).
Legal Metrology • Paper-I
The accuracy of Kelvin’s double bridge for the measurement of low resistance is high because the bridge
A)
use two pairs of resistance arms
B)
has medium value resistance in the ratio arms
C)
uses a low resistance link between standard and test resistances
D)
uses a null indicating galvanometer
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is 'uses a null indicating galvanometer' (Option D).
Legal Metrology • Paper-I
At the increasing temperature, the electrical conductivity would
A)
increase in metals as well as in intrinsic semiconductors
B)
increase in metals but decrease in intrinsic semiconductors
C)
increase in metals but decrease in intrinsic semiconductors
D)
decrease in metals as well as in intrinsic semiconductors
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'increase in metals as well as in intrinsic semiconductors' (Option A).
Legal Metrology • Paper-I
A 10 bit A/D converter is used to digitise an analog signal in the 0 to 5 range. The maximum peak to peak ripple voltage that can be allowed in the DC voltage is
A)
nearly 100 mV
B)
nearly 50 mV
C)
nearly 25 mV
D)
nearly 5.0 mV
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is 'nearly 50 mV' (Option B).
Legal Metrology • Paper-I
Steady state value of the current in the circuit
A)
0
B)
1/2
C)
2
D)
1
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is '0' (Option A).
Legal Metrology • Paper-I
In intrinsic semiconductor the free electron concentration depends on
A)
effective mass of electrons only
B)
effective mass of holes only
C)
temperature of the semiconductor
D)
width of the forbidden energy band of the conductor
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is 'effective mass of holes only' (Option B).
Legal Metrology • Paper-I
In a two port network, the condition for reciprocity in terms of h-parameters is
A)
h12 = h21
B)
h11 = h22
C)
h11 = -h22
D)
h12 = -h21
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is 'h12 = h21' (Option A).
Legal Metrology • Paper-I
The maximum power that a 12 V d.c. source with an internal resistance of 2Ω can supply to a resistive load is
A)
12 W
B)
18 W
C)
36 W
D)
48 W
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is '18 W' (Option B).
Legal Metrology • Paper-I
The capacitance and loss angle of a given capacitor specimen are best measured by
A)
Wheatstone bridge
B)
Maxwell bridge
C)
Anderson bridge
D)
Schering bridge
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is 'Maxwell bridge' (Option B).
Legal Metrology • Paper-I
In a permanent magnet moving coil instrument, if the control spring is replaced by another one having a higher spring constant, then the natural frequency and damping ratio will
A)
decrease
B)
increase and decrease respectively
C)
decrease and increase respectively
D)
increase
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is 'increase and decrease respectively' (Option B).
Legal Metrology • Paper-I
In a dual slope integrating type digital voltmeter the first integration is carried out for 10 periods of the supply frequency of 50 Hz. If the reference voltage used is 2 V the total conversion time for an input of 1 V is
A)
0.01 sec
B)
0.05 sec
C)
0.1 sec
D)
1 sec
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is '0.1 sec' (Option C).
Legal Metrology • 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
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is 'Zero' (Option A).
Legal Metrology • Paper-I
Piezoelectric effect is generally observed in
A)
insulators
B)
insulators and semiconductors
C)
conductors and superconductors
D)
conductors and semiconductors
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'insulators and semiconductors' (Option B).
Legal Metrology • Paper-I
In calibration of a dynamometer wattmeter by potentiometer, phantom loading arrangement is used because
A)
the arrangement gives accurate results
B)
the power consumed in calibration work is minimum
C)
the method gives quick results
D)
the onsite calibration is possible
Based on established principles in Electrical / Electronics Engineering, the correct and most appropriate choice is 'the onsite calibration is possible' (Option D).
