Closeness of packing is maximum in case of __________ crystal lattice.
Face centred
Simple cubic
Body centred
None of these
Correct Answer :
A. Face centred
Related Questions
Increase in the entropy of a system represents the
Degradation of energy
Decrease in system pressure
Increase in the availability of energy
Increase in the temperature
Pick out the wrong statement.
Cold cracking of a weld is due to the presence of hydrogen gas in the weld
True stress is given by, σ = σE (1 + εE), where σE and εE are engineering stress and engineering strain respectively
Phosphorous can be easily recovered in the iron blast furnace
High residual stress at the surface is beneficial for fatigue properties of a material
Which of the following is not a ferromagnetic material?
Nickel
Cobalt
Aluminium
Iron
Increasing the carbon content of steel
Reduces the upper shelf energy
Increasing the ductility transition temperature
Decreases brittleness
Decreases hardness
Stainless steel is welded using
Oxy-acetylene flame
Oxy-hydrogen flame
Arc welding
Inert gas arc welding
Which of the following is the correct nature of shear stress distribution along the cross section in a horizontal circular pipe under steady state fluid flow condition?
The normal stress is the same in all directions at a point in a fluid, only when the fluid
Is at rest & has zero viscosity
Is frictionless
Fluid layer has no motion relative to an adjacent layer of fluid
is incompressible & frictionless
__________ flux is used for the extraction of metal from its self fluxing ores.
No
Acid
Basic
Neutral
Half life of a radioactive isotope corresponds to the time required for half of the __________ to decay.
Atoms
Neutrons
Nucleons
Electrons
Load cells used for the measurement of weight has
Compact & rugged construction with an accuracy of 0.1 to 1%
No moving parts and incurs negligible deflection under load
Provision of thermal compensation and is hermetically sealed
All 'a', 'b' & 'c'
A material in which the atoms are arranged regularly in some directions but not in others, is termed as 'mesomorphous material'; an example of which is
Lead
Glass
Mica
Silver
Spark plug is provided in a/an
Engine having carburettor
Diesel engine
Compression ignition engine
Both (B) & (C)
Pick out the wrong statement.
A soft magnetic material should have high permeability and small area of hysteresis loop
Poisson's ratio of high melting point metals is more than unity
Solders generally melt at less than 185°C
Steel produced by B.O.F process is ideally suited for manufacturing flat product
The following thermocouple may be used for measuring temperature upto 1873°K.
Chromel-alumel
Copper-constantan
Platinum-platinum rhodium
Iron-constantan
Which of the following test is used for distinguishing among dry oils, semi-drying oils and non drying oils?
Elaiden test
Reichert-Meissl value test
Hunter value test
Iodine value test
Upto the critical radius of insulation, added insulation, will
Increase the heat loss
Decrease heat loss and will have no effect beyond that
Decrease heat flux
Reduce convection heat loss compared to conduction heat less
A solar cell converts the sunlight directly into __________ energy.
Thermal
Electrical
Mechanical
Chemical
The maximum thickness of the metal which can be welded using ultrasonic welding is __________ mm.
0.5
3
10
25
The phenomenon occurring during explosion of a hydrogen bomb is
Nuclear fission
Nuclear fusion
A combination of both nuclear fission & fusion
None of these
Basic open hearth furnace (BOF) is not used for producing __________ steel.
Killed
Rimming
High alloy
None of these
Probability of cavitation occuring becomes very high, when the local __________ resulting in water bubbles formation, which on rupture cause cavitation
Pressure falls below the vapour pressure
Pressure becomes very high
Temperature becomes low
All 'a', 'b' & 'c'
M10 index of coke indicates its
Compressive strength
Hardness
Abrasion resistance
Impact strength
Boiler draught of 10 mm water column is equivalent to
1 kgf/m2
10 kgf/m2
10 kgf/mm2
1 kgf/mm2
Work done by a/an __________ process is determined by ∫p. dv
Adiabatic
Quasi-static
Isothermal
Isentropic
When dry bulb temperature & wet bulb temperature of moist air is the same, it means that the
Partial pressure of water vapour is less than the total pressure
Humidity is < 100% & dew point temperature of air has not reached
Dew point temperature of air has not reached & air is not saturated fully
Air is fully saturated
The only suitable method for hardening the low carbon steel is case hardening. Which of the following is a case hardening process?
Cyaniding
Sherardizing
Spheroidising
None of these
Which of the following emissions in the exhaust gas of an I.C. engine causes the formation of photochemical smog?
Nitrogen oxides
Hydrocarbons
Both 'a' & 'b'
Carbon monoxide
In inventory control theory, the economic order quantity (EOQ) is the
Lot size corresponding to break even analysis
Average level of inventory
Optimum lot size
None of these
Limestone addition in the blast furnace is done to flux __________ present in the raw materials.
SiO2
Al2O3
MnO2
P
The starting of a car takes time in winter, because the
Octane number of fuel is decreased
Fuel supply for ignition is not sufficient
Vaporisation of the fuel is decreased
Pour point of fuel decreases