Legal Metrology • Electronics & Communication Engineering Paper-II
A good current buffer has
A)
Low-input impedance and low-output impedance
B)
Low-input impedance and high-output impedance
C)
High-input impedance and low-output impedance
D)
High-input impedance and high-output impedance
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is 'Low-input impedance and high-output impedance' (Option B).
Legal Metrology • Electronics & Communication Engineering Paper-II
Ripple factor of half wave rectifier is
A)
1.414
B)
1.21
C)
1.3
D)
0.48
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is '0.48' (Option D).
Legal Metrology • Electronics & Communication Engineering Paper-II
The biasing circuit has a stability factor of 50. If due to temperature change, ICBO changes by 1 μA, then IC will change by
A)
100pA
B)
25pA
C)
20pA
D)
50μA
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is '100pA' (Option A).
Legal Metrology • Electronics & Communication Engineering Paper-II
The Maxwell’s equation, ∇ x H = J + ∂D/∂t is based on
A)
Ampere’s law
B)
Gauss’s law
C)
Faraday’s law
D)
Coulomb’s law
Based on established principles in Electrical / Electronics Engineering, the correct and most clinically/technically appropriate choice is 'Gauss’s law' (Option B).
Legal Metrology • Electronics & Communication Engineering Paper-II
The depth of penetration of a wave in a lossy dielectric increases with increasing
A)
Conductivity
B)
Permeability
C)
Wavelength
D)
Permittivity
Greater wavelength means weaker attenuation/greater penetration in the usual lossy-medium regime.
Legal Metrology • Electronics & Communication Engineering Paper-II
What is the duty cycle of the output of an astable multivibrator?
A)
50%
B)
100%
C)
75%
D)
55%
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is '100%' (Option B).
Legal Metrology • Electronics & Communication Engineering Paper-II
For good stabilization in voltage divider bias, the current IE flowing through R1 and R2 should be equal to or greater than
A)
10IB
B)
3IB
C)
2IB
D)
4IB
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is '4IB' (Option D).
Legal Metrology • Electronics & Communication Engineering Paper-II
A uniform plane electromagnetic wave incident normally on a plane surface of a dielectric material is reflected with a VSWR of 3. What is the percentage of incident power that is reflected?
A)
10%
B)
25%
C)
50%
D)
75%
The reflection coefficient Γ = (VSWR - 1)/(VSWR + 1) = (3 - 1)/(3 + 1) = 0.5. Reflected power is |Γ|^2 = 0.25 or 25%.
Legal Metrology • Electronics & Communication Engineering Paper-II
Find the output voltage of an ideal op-amp. If V₁ and V₂ are the two input voltages
A)
Vo=V₁-V₂
B)
Vo=A*x(V₁-V₂)
C)
Vo=Ax(V₁+V₂)
D)
Vo=V₁xV₂
For an ideal differential op-amp, Vo=A(V1−V2).
Legal Metrology • Electronics & Communication Engineering Paper-II
When is a flip-flop said to be transparent?
A)
When the Q output is opposite the input
B)
When the Q output follows the input
C)
When you can see through the IC packaging
D)
When the Q output is complementary of the input
A transparent latch is one in which Q follows the input while the latch is enabled.
Legal Metrology • Electronics & Communication Engineering Paper-II
Given that a feedback network is shunt-series, and output load is 10kΩ, what is the output voltage across it given that transfer gain is 10, source current is 20mA and feedback current is 10mA?
A)
1V
B)
2V
C)
10V
D)
20V
For shunt-series feedback, I_F=βI_L, so I_L=10 mA/10=1 mA and V_L=1mA×10kΩ=10V.
Legal Metrology • Electronics & Communication Engineering Paper-II
The canonical sum of product form of the function y(A,B) = A + B is
A)
AB + BB + A'A
B)
AB + AB' + A'B
C)
BA + BA' + A'B'
D)
AB' + A'B + A'B'
A+B=1 for minterms AB, AB′, and A′B, giving AB+AB′+A′B.
Legal Metrology • Electronics & Communication Engineering Paper-II
A flip-flop is popularly known as
A)
Astable multivibrator
B)
Bistable multivibrator
C)
Monostable multivibrator
D)
None of these
A flip-flop is a bistable multivibrator because it has two stable states.
Legal Metrology • Electronics & Communication Engineering Paper-II
For a dipole antenna
A)
The radiation intensity is maximum along the normal to the dipole axis
B)
The current distribution along its length is uniform irrespective of the length
C)
The effective length equals its physical length
D)
The input impedance is independent of the location of the feed-point
Based on established principles in this specific field of study, the correct and most clinically/technically appropriate choice is 'The radiation intensity is maximum along the normal to the dipole axis' (Option A).
Legal Metrology • Electronics & Communication Engineering Paper-II
For a given sample-and-hold circuit, if the value of the hold capacitor is increased, then
A)
Droop rate decreases and acquisition time decreases
B)
Droop rate decreases and acquisition time increases
C)
Droop rate increases and acquisition time decreases
D)
Droop rate increases and acquisition time increases
A larger hold capacitor decreases the droop rate but takes longer to charge, increasing acquisition time.
Legal Metrology • Electronics & Communication Engineering Paper-II
The far field of an antenna varies with distance r as
A)
1/r
B)
1/r²
C)
1/r³
D)
√r
Based on established principles in this specific field of study, the correct and most clinically/technically appropriate choice is '1/r²' (Option B).
Legal Metrology • Electronics & Communication Engineering Paper-II
If the differential voltage gain and the common mode voltage gain of a differential amplifier are 48 dB and 2 dB respectively, then its common mode rejection ratio is
A)
23 dB
B)
25 dB
C)
46dB
D)
50dB
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is '46dB' (Option C).
Legal Metrology • Electronics & Communication Engineering Paper-II
Distortion level in the output of RC phase shift network will be less than
A)
1%
B)
2%
C)
5%
D)
10%
RC phase-shift oscillators are known for low distortion; the standard MCQ answer is less than 5%.
Legal Metrology • Electronics & Communication Engineering Paper-II
For a transistor amplifier with self-biasing network, the following components are used: RE=4Ω, RC=4 kΩ, RB=4 kΩ and VCC=1 K. the appropriate value of the stability factor S will be
A)
4
B)
3
C)
2
D)
1.5
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is '3' (Option B).
Legal Metrology • Electronics & Communication Engineering Paper-II
Units of the vector magnetic potential are
A)
A/m²
B)
A/m
C)
Wh/m²
D)
Wb/m
Based on established principles in Electrical / Electronics Engineering, the correct and most clinically/technically appropriate choice is 'Wh/m²' (Option C).
Legal Metrology • Electronics & Communication Engineering Paper-II
To construct a 512 K x 8 memory , the number of 32 K x 4 memory circuit required is
A)
16
B)
32
C)
8
D)
64
Number of chips = (Capacity needed) / (Capacity per chip) = (512K * 8) / (32K * 4) = 16 * 2 = 32.
Legal Metrology • Electronics & Communication Engineering Paper-II
A parabolic dish antenna has a conical beam 2° wide. The directivity of the antenna is approximately
A)
20dB
B)
30dB
C)
40dB
D)
50dB
In the context of Unmapped / long tail, the most appropriate and technically accurate answer is '20dB' (Option A).
Legal Metrology • Electronics & Communication Engineering Paper-II
The unit of ∇ x H is
A)
Ampere
B)
Ampere/meter
C)
Ampere/meter²
D)
Ampere-meter
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is 'Ampere/meter²' (Option C).
Legal Metrology • Electronics & Communication Engineering Paper-II
Which of the transistor model is most preferred for the analysis of a transistor circuit both at mid-band and at high frequencies?
A)
h-parameter model
B)
y-parameter model
C)
s-parameter model
D)
Hybrid -2z model
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is 's-parameter model' (Option C).
Legal Metrology • Electronics & Communication Engineering Paper-II
What is the role of emitter resistance in the transistor amplifying circuit?
A)
To prevent thermal runaway
B)
To prevent increase in gain
C)
To lower the output impedance
D)
To increase gain
In the context of Electrical / Electronics Engineering, the most appropriate and technically accurate answer is 'To prevent thermal runaway' (Option A).
