Legal Metrology • Paper-I
In turbofan engine, fan is used
A)
To compress the inlet air more efficiently
B)
To increase the total thrust of the engine
C)
Both (a) & (b)
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
Multistage centrifugal pumps are used to obtain
A)
high discharge
B)
high head
C)
pumping of viscous fluids
D)
high head and high discharge
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'high head and high discharge' (Option D).
Legal Metrology • Paper-I
The dew point temperature is less than the wet bulb temperature for
A)
Standard air
B)
Unsaturated air
C)
Both saturated and unsaturated air
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
The rate of energy transferred by convection to that by conduction is called
A)
Stanton number
B)
Nusselt number
C)
Biot number
D)
Peclet number
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'Stanton number' (Option A).
Legal Metrology • Paper-I
Boyle’s law is applicable to gases under
A)
only Small range of pressure
B)
high range of pressure
C)
steady range of pressure
D)
all range of pressure
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'only Small range of pressure' (Option A).
Legal Metrology • Paper-I
Francis, Kaplan and propeller turbines fall under the category of
A)
Impulse turbines
B)
Reaction turbines
C)
Axial flow turbines
D)
Mixed flow turbines
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'Reaction turbines' (Option B).
Legal Metrology • Paper-I
The second law of thermodynamics deals with
A)
direction of process and quality of energy
B)
energy balance
C)
balance of internal energy
D)
system efficiency
The second law governs the direction/feasibility of processes and the quality or availability of energy.
Legal Metrology • Paper-I
Which of the following refrigerants has lowest freezing point
A)
Freon-12
B)
NH3
C)
CO2
D)
Freon-22
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'NH3' (Option B).
Legal Metrology • Paper-I
When H1=total heat of air entering the coil (heating or cooling), H2= total heat of the air leaving the coil (heating or cooling), H3= total heat of air at the end of the process (humidification or dehumidification), then the sensible heat factor (H2-H1)/(H3-H1) represents the process of
A)
Cooling and humidification
B)
Cooling and dehumidification
C)
Heating and humidification
D)
Heating and dehumidification
Based on established principles in the relevant subject area, the correct and most appropriate choice is 'Cooling and humidification' (Option A).
Legal Metrology • Paper-I
Which one is having highest value of overall heat transfer coefficient?
A)
Feed water heaters
B)
Steam condensers
C)
Alcohol condensers
D)
Ammonia condensers
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'Ammonia condensers' (Option D).
Legal Metrology • Paper-I
The velocity of a fluid particle at the centre of the pipe section is
A)
Maximum
B)
Minimum
C)
Average
D)
r.m.s
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'Minimum' (Option B).
Legal Metrology • Paper-I
The dynamic viscosity of a liquid is 1.2 × 10-4 Ns/m2, whereas, the density is 600 kg/m3. The kinematic viscosity in m2/s is
A)
72 × 10-3
B)
20 × 10-8
C)
7.2 × 103
D)
70 × 106
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is '72 × 10-3' (Option A).
Legal Metrology • Paper-I
The pattern of flow in the boundary layer is judged by the
A)
Reynolds number
B)
Fourier number
C)
Peclet number
D)
Grashof number
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'Peclet number' (Option C).
Legal Metrology • Paper-I
Work is a
A)
point function
B)
path function
C)
depends on the state
D)
none of these
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'path function' (Option B).
Legal Metrology • Paper-I
The COP of a domestic refrigerator
A)
is less than 1
B)
is more than 1
C)
is equal to 1
D)
depends upon the make
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'is equal to 1' (Option C).
Legal Metrology • Paper-I
During sensible heating of moist air, enthalpy
A)
increases
B)
decreases
C)
remains constant
D)
none of these
Based on established principles in the relevant subject area, the correct and most appropriate choice is 'remains constant' (Option C).
Legal Metrology • Paper-I
Newton’s law of viscosity states that
A)
the shear stress applied to the fluid is directly proportional to the velocity gradient (du/dy)
B)
the shear stress applied to the fluid is inversely proportional to the velocity gradient (du/dy)
C)
the shear stress applied to the fluid is directly proportional to the specific weight of the fluid
D)
the shear stress applied to the fluid is inversely proportional to the specific weight of the fluid
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'the shear stress applied to the fluid is inversely proportional to the velocity gradient (du/dy)' (Option B).
Legal Metrology • Paper-I
In the process of heat transfer through extended surfaces or fins, the entire surface area is at
A)
the same constant temperature
B)
different temperatures
C)
maximum base temperature
D)
minimum temperature
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'the same constant temperature' (Option A).
Legal Metrology • Paper-I
In a free vortex motion, the radial component of velocity everywhere is
A)
maximum
B)
minimum
C)
zero
D)
non-zero and finite
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'non-zero and finite' (Option D).
Legal Metrology • Paper-I
Which type of nozzle is used in a steam turbine
A)
Convergent
B)
Divergent
C)
Convergent-divergent
D)
None
Based on established principles in the relevant subject area, the correct and most appropriate choice is 'nan' (Option D).
Legal Metrology • Paper-I
The pressure that seawater exerts on a submerged submarine is called
A)
underwater pressure.
B)
liquid pressure.
C)
submerged pressure.
D)
hydrostatic pressure
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'underwater pressure.' (Option A).
Legal Metrology • Paper-I
Which of the following is NOT a type of heat pump?
A)
vapour compression type
B)
vapour absorption type
C)
both (a) & (b)
D)
none of these
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'both (a) & (b)' (Option C).
Legal Metrology • Paper-I
A body floats in stable equilibrium
A)
when the metacentre is above C.G.
B)
when its metacentric height is zero
C)
when its C.G. is below its center of buoyancy
D)
metacentre has nothing to do with position of C.G. for determining stability
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'metacentre has nothing to do with position of C.G. for determining stability' (Option D).
Legal Metrology • Paper-I
The flow on two sides of a normal shock wave is
A)
subsonic
B)
sonic
C)
supersonic
D)
supersonic on one side and subsonic on the other side
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'supersonic on one side and subsonic on the other side' (Option D).
Legal Metrology • Paper-I
COP of a Carnot refrigeration cycle is greater than
A)
vapour compression cycle
B)
reversed Brayton cycle
C)
vapour absorption cycle
D)
all of these
Based on established principles in Mechanical Engineering, the correct and most appropriate choice is 'all of these' (Option D).
