Legal Metrology • Mechanical Engineering Paper-I
Operating characteristic curves of turbine means curves drawn at constant
A)
head
B)
discharge
C)
speed
D)
efficiency
In the context of Mechanical Engineering, the most appropriate and technically accurate answer is 'discharge' (Option B).
Legal Metrology • Mechanical Engineering Paper-I
Reciprocating compressors have maximum capacity of m³/min
A)
50
B)
100
C)
200
D)
300
In the context of Mechanical Engineering, the most appropriate and technically accurate answer is '100' (Option B).
Legal Metrology • Mechanical Engineering Paper-I
Pseud-plastic is a fluid for which
A)
dynamic viscosity decreases as the rate of shear increase
B)
newton‘s law of viscosity holds good
C)
dynamic viscosity increases as the rate of shear increases
D)
dynamic viscosity increases with the time for which the shearing forces are applied
Based on established principles in Mechanical Engineering, the correct and most clinically/technically appropriate choice is 'dynamic viscosity increases as the rate of shear increases' (Option C).
Legal Metrology • Mechanical Engineering Paper-I
Which of the following water turbine does not require a draft tube?
A)
Propeller turbine
B)
Pelton turbine
C)
Kaplan turbine
D)
Francis turbine
In the context of Mechanical Engineering, the most appropriate and technically accurate answer is 'Francis turbine' (Option D).
Legal Metrology • Mechanical Engineering Paper-I
Low-torque high-speed motors are used in
A)
cranes
B)
winches
C)
fans
D)
all of the above
Based on established principles in this specific field of study, the correct and most clinically/technically appropriate choice is 'all of the above' (Option D).
Legal Metrology • Mechanical Engineering Paper-I
Heat transfer by radiation is encountered least in
A)
boiler furnace
B)
insulated steam pipe
C)
electric bulb
D)
nuclear reactor
An insulated steam pipe has the smallest radiative heat loss among the choices.
Legal Metrology • Mechanical Engineering Paper-I
An ideal gas with an internal energy U initially at 0°C is heated to 273°C. What is the new internal energy in terms of U?
A)
U
B)
(1/2)U
C)
(1/4)U
D)
2U
Internal energy U of an ideal gas is proportional to absolute temperature T. T1 = 273K, T2 = 546K, so U doubles.
Legal Metrology • Mechanical Engineering Paper-I
Which law of thermodynamics is known as law of nature?
A)
Zeroth law
B)
First Law
C)
Second Law
D)
Third law
The Second Law of Thermodynamics dictates the direction of spontaneous natural processes.
Legal Metrology • Mechanical Engineering Paper-I
If m_a = mass of dry air and m_v = mass of water vapour in the air-water vapour mixture, then the humidity ratio is given by
A)
m_v / m_a
B)
m_a / m_v
C)
m_v / (m_a + m_v)
D)
m_a / (m_a + m_v)
Humidity ratio is the mass of water vapour per unit mass of dry air, m_v/m_a.
Legal Metrology • Mechanical Engineering Paper-I
The efficiency of pelton wheel shall be maximum if the ratio of jet velocity to tangential velocity of the wheel is
A)
1/2
B)
1
C)
2
D)
4
Based on established principles in Mechanical Engineering, the correct and most clinically/technically appropriate choice is '4' (Option D).
Legal Metrology • Mechanical Engineering Paper-I
Maximum delivery pressure for rotary bladed compressor is usually restricted to bar.
A)
5
B)
10
C)
20
D)
50
In the context of Mechanical Engineering, the most appropriate and technically accurate answer is '5' (Option A).
Legal Metrology • Mechanical Engineering Paper-I
What is the use of reheat cycle in steam turbines?
A)
To remove the moisture from the steam
B)
To increase the steam temperature
C)
To increase steam pressure
D)
None of these
Reheating steam in turbines helps to remove moisture content, preventing blade erosion.
Legal Metrology • Mechanical Engineering Paper-I
The viscosity of water with respect to air is about
A)
50 times
B)
55 times
C)
60 times
D)
65 times
In the context of Mechanical Engineering, the most appropriate and technically accurate answer is '65 times' (Option D).
Legal Metrology • Mechanical Engineering Paper-I
The unit power P_u of a turbine developing a power P under a head H is
A)
P/H
B)
P/H^0.5
C)
P/H^0.5 S^2
D)
P/H^0.5 S
In the context of Mechanical Engineering, the most appropriate and technically accurate answer is 'P/H^0.5 S^2' (Option C).
Legal Metrology • Mechanical Engineering Paper-I
The total energy developed by the hydraulic oil in a system is given as
A)
Total energy = (Potential energy + Pressure energy)
B)
Total energy = (Potential energy + Kinetic energy)
C)
Total energy = (Potential energy — Kinetic energy)
D)
None of the above
Bernoulli/flow energy includes pressure, potential, and kinetic terms; none of the listed two-term expressions is complete.
Legal Metrology • Mechanical Engineering Paper-I
The property of stream function ψ is:
A)
ψ is constant everywhere on any stream line
B)
the flow around any path in the fluid is zero for continuous flow
C)
the velocity vector may be found by differentiating the stream function
D)
all of the above
Based on established principles in Mechanical Engineering, the correct and most clinically/technically appropriate choice is 'all of the above' (Option D).
Legal Metrology • Mechanical Engineering Paper-I
Nozzle used in rocket engine is
A)
convergent nozzle
B)
divergent nozzle
C)
convergent-divergent nozzle
D)
none of the above
In the context of Mechanical Engineering, the most appropriate and technically accurate answer is 'none of the above' (Option D).
Legal Metrology • Mechanical Engineering Paper-I
Two walls of same thickness and cross-sectional area have thermal conductivities in the ratio 1:2. If the same temperature difference is maintained across the wall faces, the ratio of heat flow Q₁/Q₂ will be
A)
1/2
B)
1
C)
2
D)
4
With equal L, A, and ΔT, Q∝k; therefore Q1/Q2=k1/k2=1/2.
Legal Metrology • Mechanical Engineering Paper-I
The intensity of solar radiation (kW/m²) on earth is
A)
1
B)
2
C)
5
D)
10
Solar irradiance near the top of the atmosphere/surface under strong sunlight is about 1 kW/m².
Legal Metrology • Mechanical Engineering Paper-I
For a hypersonic flow, the mach number is
A)
unity
B)
greater than unity
C)
greater than 2
D)
greater than 4
In the context of Mechanical Engineering, the most appropriate and technically accurate answer is 'greater than unity' (Option B).
Legal Metrology • Mechanical Engineering Paper-I
Which of the following is not an accessory of the boiler
A)
condenser
B)
economiser
C)
air-preheater
D)
feed water pump
A condenser belongs to the power-cycle/condensing plant, not to the boiler itself.
Legal Metrology • Mechanical Engineering Paper-I
The rate of heat transfer in drop-wise condensation is than firm condensation.
A)
larger
B)
smaller
C)
equal
D)
none
In the context of Mechanical Engineering, the most appropriate and technically accurate answer is 'equal' (Option C).
Legal Metrology • Mechanical Engineering Paper-I
A jet of water impinges normally on a fixed plate. The force exerted on the plate will be
A)
ρAV²
B)
ρAV²/2
C)
2ρAV²
D)
2ρAV²/2
In the context of Mechanical Engineering, the most appropriate and technically accurate answer is 'ρAV²/2' (Option B).
Legal Metrology • Mechanical Engineering Paper-I
Thermal radiations occur in the portion of electromagnetic spectrum between the wavelengths
A)
10⁻² to 10⁴ micron
B)
10 to 10² micron
C)
0.1 to 10² micron
D)
10² micron onwards
Thermal radiation spans roughly 0.1 to 100 μm in the common engineering definition.
Legal Metrology • Mechanical Engineering Paper-I
The value of speed ratio for a Kaplan turbine is about
A)
0.5
B)
0.9
C)
1.5
D)
2.0
In the context of Mechanical Engineering, the most appropriate and technically accurate answer is '1.5' (Option C).
