Legal Metrology • Paper-I
A given copper of 10Ω resistance is stretched to double its original length, Its modified resistance will be
A)
5Ω
B)
7Ω
C)
20Ω
D)
40Ω
If length doubles while volume stays constant, area halves, so R=ρL/A becomes four times: 40 Ω.
Legal Metrology • Paper-I
In CMOS logic circuit the n-MOS transistor acts as:
A)
Not used in CMOS circuits
B)
Load
C)
Pull up network
D)
Pull down network
In CMOS, NMOS devices form the pull-down network.
Legal Metrology • Paper-I
L/R has the dimension of
A)
Time
B)
Capacitance
C)
Inductance
D)
Resistance
L/R represents the time constant (τ) of an RL circuit, which has the unit of time.
Legal Metrology • Paper-I
The input impedance of a transistor is as compared to MOSFET.
A)
Very high
B)
Equal
C)
High
D)
Low
In the context of Unmapped / long tail, the most appropriate and technically accurate answer is 'Equal' (Option B).
Legal Metrology • Paper-I
Hall effect is useful for the measurement of a semiconductor’s
A)
Mobility, carrier, concentration and temperature
B)
Type (n-type or p-type), conductivity and temperature
C)
Type (n-type or p-type), mobility and carrier concentration
D)
Mobility, conductivity and temperature
Based on established principles in Electrical / Electronics Engineering, the correct and most clinically/technically appropriate choice is 'Type (n-type or p-type), mobility and carrier concentration' (Option C).
Legal Metrology • Paper-I
In an optical fiber, the refractive index of the cladding material should be,
A)
Nearly unity
B)
Very low
C)
Less than that of the core
D)
More than that of the core
In the context of Unmapped / long tail, the most appropriate and technically accurate answer is 'Very low' (Option B).
Legal Metrology • Paper-I
N-type semiconductor has
A)
Immobile negative donor ion
B)
Immobile positive donor ion
C)
Holes (majority carrier)
D)
No minority carrier
Based on established principles in Electrical / Electronics Engineering, the correct and most clinically/technically appropriate choice is 'Immobile negative donor ion' (Option A).
Legal Metrology • Paper-I
A network has 10 nodes and 17 branches. The number of different node pair voltage would be,
A)
25
B)
35
C)
45
D)
55
For n nodes, the number of node pair voltages is n(n-1)/2. So, 10*9/2 = 45.
Legal Metrology • Paper-I
Base to emitter voltage in forward biased transistor decreases with the increase of temperature at the following rate,
A)
3.5mV/degree C
B)
7.5mV/degree C
C)
2.5mV/degree C
D)
0.5 mV/degree C
In the context of Unmapped / long tail, the most appropriate and technically accurate answer is '2.5mV/degree C' (Option C).
Legal Metrology • Paper-I
What is the set of all values of z for which X(z) attains a finite value?
A)
Radius of convergence
B)
Radius of divergence
C)
Feasible solution
D)
No solution
The set of z-values for which X(z) is finite is the region of convergence (ROC); A is the closest listed wording.
Legal Metrology • Paper-I
VMOS stands for:
A)
Voltage MOS
B)
Vertical MOS
C)
Variable MOS
D)
VLSIMOS
In the context of Unmapped / long tail, the most appropriate and technically accurate answer is 'Voltage MOS' (Option A).
Legal Metrology • Paper-I
What does the quality factor of a dielectric mean?
A)
it is related to the value of the permittivity of the material
B)
it is related to the ratio between maximum stored energy and average power loss in the dielectric
C)
It is related to the breakdown voltage of the dielectric
D)
It is related to the resistivity of the material
Based on established principles in Mechanical Engineering, the correct and most clinically/technically appropriate choice is 'It is related to the breakdown voltage of the dielectric' (Option C).
Legal Metrology • Paper-I
A transistor’s current gain of 0.99 in the CB mode. its current gain in the CC mode is,
A)
33
B)
66
C)
50
D)
100
In the context of Unmapped / long tail, the most appropriate and technically accurate answer is '100' (Option D).
Legal Metrology • Paper-I
Natural Group material are
A)
Quartz, Rochelle salt
B)
LiSO3, BaTiO3
C)
LiSO3, PbTiO3
D)
Quartz, PbZrO3
In the context of Mechanical Engineering, the most appropriate and technically accurate answer is 'LiSO3, PbTiO3' (Option C).
Legal Metrology • Paper-I
A bipolar junction transistor has a common base forward short circuit current gain of 0.99. Its common emitter forward short circuit current gain will be
A)
9
B)
99
C)
999
D)
9999
In the context of Unmapped / long tail, the most appropriate and technically accurate answer is '99' (Option B).
Legal Metrology • Paper-I
CMOS inverter has output impedance.
A)
Extremely high
B)
Very high
C)
High
D)
Low
A CMOS inverter has low output resistance when on, allowing it to drive a load effectively.
Legal Metrology • Paper-I
If an impedance ZL is connected across a voltage source V with source impedance ZS, then for maximum power transfer, the load impedance must be equal to,
A)
source impedance ZS
B)
complex conjugate of ZS
C)
real part of ZS
D)
imaginary part of ZS
According to the Maximum Power Transfer Theorem for AC circuits, ZL must be the complex conjugate of ZS.
Legal Metrology • Paper-I
ICs are generally made of
A)
Silicon
B)
Copper
C)
Aluminum
D)
GaAs
Silicon is the dominant material for conventional integrated circuits.
Legal Metrology • Paper-I
The superposition theorem is applicable to
A)
Only current
B)
Only voltage
C)
Only power
D)
Current, Voltage and Power
Superposition applies only to linear functions (current and voltage), not to power which is proportional to the square.
Legal Metrology • Paper-I
What is the z-transform of the signal x[n] = a^n u(n)?
A)
X(z) = z / (z-a)
B)
X(z) = 1 / (z-a)
C)
X(z) = z / (z+a)
D)
X(z) = 1 / (z+a)
The standard z-transform of a step function a^n u(n) is z / (z-a).
Legal Metrology • Paper-I
A source is delivering maximum power to a resistance through a network. The ratio of power delivered to the source power
A)
is always 0.5
B)
may be 0.5 or less
C)
may be 0.5 or less or more
D)
maybe 0.5 or more
At maximum power transfer, efficiency is 50%, meaning the ratio of power delivered to the load vs source is 0.5.
Legal Metrology • Paper-I
Effective Q of the equivalent electrical circuit of a quartz crystal is of the order of
A)
2,00,000
B)
3,00,000
C)
4,00,000
D)
5,00,000
Quartz crystals are highly stable and have an exceptionally high Q factor, typically in the range of 2,00,000.
Legal Metrology • Paper-I
In the forward blocking mode of a silicon controlled rectifier, the SCR is
A)
In natural state
B)
In ON state
C)
In forward bias state
D)
In OFF state
Forward blocking means the SCR is forward biased at the anode-cathode junction but remains OFF until triggered.
Legal Metrology • Paper-I
Find the Z-transform of δ(n+3)
A)
z^3
B)
z^-3
C)
z
D)
z^-1
Z{δ(n+3)}=z³ under the standard bilateral Z-transform definition.
Legal Metrology • Paper-I
For an NPN bipolar transistor, what is the mainstream of current in the base region?
A)
Diffusion of electrons
B)
Diffusion of holes
C)
Drift of electrons
D)
Drift of holes
In the context of Unmapped / long tail, the most appropriate and technically accurate answer is 'Diffusion of electrons' (Option A).
