Legal Metrology • Paper-I
A non-dimensional number generally associated with natural convection heat transfer is
A)
Grashoff number
B)
Nusselt number
C)
Weber number
D)
Prandtl number
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'Weber number' (Option C).
Legal Metrology • Paper-I
The function of an inter cooler in a gas turbine plant is
A)
to cool the exhaust gas from the turbine
B)
to cool compressed air from compressor
C)
to cool atmospheric air before inlet to compressor
D)
to cool the compressed air in between the stages
Based on established principles in the relevant subject area, the correct and most appropriate choice is 'to cool compressed air from compressor' (Option B).
Legal Metrology • Paper-I
In an isothermal process
A)
temperature increases gradually
B)
volume remains constant
C)
change in internal energy is zero
D)
enthalpy change is maximum
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'temperature increases gradually' (Option A).
Legal Metrology • Paper-I
Which of the following is the correct relation between centroid (G) and the centre of pressure (P) of a plane submerged in a liquid?
A)
G is always below P
B)
P is always below G
C)
G is either at P or below it.
D)
P is either at G or below it.
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'G is always below P' (Option A).
Legal Metrology • Paper-I
The presence of which of the following units in a vapor compression system is adversely affected by the presence of moisture?
A)
Condenser
B)
Expansion valve
C)
Evaporator
D)
Compressor
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'Expansion valve' (Option B).
Legal Metrology • Paper-I
In a two-stroke engine, one power stroke is obtained in
A)
one revolution of the crank shaft
B)
two revolutions of the crank shaft
C)
four revolutions of the crank shaft
D)
none of these
Based on established principles in the relevant subject area, the correct and most appropriate choice is 'none of these' (Option D).
Legal Metrology • Paper-I
Which of the following cycles uses air as the refrigerant
A)
Ericsson
B)
Stirling
C)
Carnot
D)
Bell-coleman
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'Stirling' (Option B).
Legal Metrology • Paper-I
The discharge in an open channel corresponding to critical depth is
A)
Zero
B)
Minimum
C)
Maximum
D)
None of these
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'None of these' (Option D).
Legal Metrology • Paper-I
Which one of the following is a CFC refrigerant?
A)
R 744
B)
R 290
C)
R 502
D)
R 718
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'R 744' (Option A).
Legal Metrology • Paper-III
Which mode has the lowest cut off frequency in circular wave guides?
A)
TE01
B)
TE11
C)
TE20
D)
TE21
TE11 is the dominant mode of a circular waveguide and has the lowest cutoff frequency.
Legal Metrology • Paper-III
Suppose that the modulating signal is m(t) = 2cos(2πf_m t) and the carrier signal is X_c(t) = A_c cos(2πf_c t). Which one of the following is a conventional AM signal without over-modulation?
A)
Am(t)cos(2πf_c t)
B)
[1 + m(t)]cos(2πf_c t)
C)
A_c cos(2πf_c t) + 0.25A_c cos(2πf_c t)cos(2πf_m t)
D)
A_c cos(2πf_c t)cos(2πf_m t) + A_c sin(2πf_c t)sin(2πf_m t)
Correct option: C — A_c cos(2πf_c t) + 0.25A_c cos(2πf_c t)cos(2πf_m t). This matches the standard definition/result for the stated question.
Legal Metrology • Paper-III
Memory of computer which is used to speed up the computer processing is
A)
BIOS
B)
Cache Memory
C)
RAM
D)
ROM
Correct option: B — Cache Memory. This matches the standard definition/result for the stated question.
Legal Metrology • Paper-III
Most commonly used antenna with television receivers
A)
Loop antenna
B)
Rhombic antenna
C)
V-antenna
D)
Yagi- antenna
Yagi-Uda antennas provide directional gain and are widely used for TV reception.
Legal Metrology • Paper-III
The skip distance is
A)
Same for each layer
B)
Independent of frequency
C)
Independent of the state of ionisation
D)
Independent of transmitted power
Skip distance depends on operating frequency, ionization and transmission conditions; it is not fixed by transmitted power alone.
Legal Metrology • Paper-III
Quantization noise can be reduce by
A)
Using de-emphasis circuit
B)
Using RF amplifier in the receiver
C)
Increasing the number of quantization levels
D)
Sending sloping pulses
Increasing the number of quantization levels reduces quantization step size and therefore quantization noise.
Legal Metrology • Paper-III
The effective length of an antenna is measure of
A)
Length of antenna neglecting fringing effect
B)
Effectiveness of the antenna as a radiator/collector of electromagnetic energy
C)
Power consumed by the antenna
D)
Range of the antenna
Effective length describes how effectively an antenna converts incident field to received voltage/current, or vice versa.
Legal Metrology • Paper-III
Boosting of higher frequency at the transmitter is done by using
A)
De-emphasis
B)
AGC circuit
C)
Pre-emphasis
D)
Armstrong method
Correct option: C — Pre-emphasis. This matches the standard definition/result for the stated question.
Legal Metrology • Paper-III
Which ionosphere layer is responsible for return of a radiation at frequency of 30 MHz?
A)
D
B)
E
C)
F
D)
All of these
The E region can reflect some HF frequencies around this range.
Legal Metrology • Paper-III
The address bus of Intel 8085 is 16-bit wide and hence the memory which can be accessed by this address bus is
A)
2 k bytes
B)
4 k bytes
C)
16 k bytes
D)
64 k bytes
TRAP is the highest-priority 8085 interrupt.
Legal Metrology • Paper-III
As an ideal local oscillator for microwave frequency measurements, the most suitable microwave source is a
A)
Multi cavity magnetron
B)
Reflex klystron
C)
Double cavity klystron
D)
Travelling Wave Tube
The reflex klystron is widely used as a stable microwave local oscillator.
Legal Metrology • Paper-III
In AM, the modulation index lies between
A)
-1 and 1
B)
0 and 1
C)
1 and
D)
and
Correct option: B — 0 and 1. This matches the standard definition/result for the stated question.
Legal Metrology • Paper-III
A microwave antenna is used in radar for ____________.
A)
Data finding
B)
Radiation finding
C)
Direction finding
D)
Both (a) and (c)
Correct option: C — Direction finding. This matches the standard definition/result for the stated question.
Legal Metrology • Paper-III
Microwave frequencies are normally regarded as those in the range of
A)
1 to 100 Hz
B)
100 Hz to 1000 Hz
C)
1 to 100 GHz
D)
1 to 100 MHz
A high resistance is connected in series to limit the current through the voltmeter movement.
Legal Metrology • Paper-III
Where the result of an arithmetic and logical operation are stored ?
A)
In accumulator
B)
In cache memory
C)
In ROM
D)
In instruction registry
Correct option: A — In accumulator. This matches the standard definition/result for the stated question.
Legal Metrology • Paper-III
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 is equal to its physical length
D)
The input impedance is independent of the location of the feed point
A half-wave dipole radiates maximum power broadside, normal to its axis.
