Thermit welding is categorised as the __________ welding.
Forge
Fusion
Resistance
Arc
Correct Answer :
B. Fusion
Related Questions
Sudden fall of atmospheric pressure by a large amount is an indication of the
Rain
Cold wave
Storm
Fair weather
The joint for soldering is supported by binding wire made of
Mild steel
Copper
Soft iron
Stainless steel
Liquid nitrogen containers can be made from
Ferritic stainless steel
HSLA steel
Titanium
Austenitic stainless steel
Notched bar test is used for testing the __________ of a material.
Impact strength
Endurance limit
Machinability
Corrosion resistance
In multipass welds, shot peening is done after each pass to
Close the surface porosity
Break the continuity of columnar grains
Flatten the weldment
Introduce texture in the weld
Lead is added to 60:40 brass primarily to improve
Machinability
Corrosion resistance
Fluidity
Strength
There are one octahedral void and __________ tetrahedral void in the closest packing of atoms.
One
Two
Three
None of these
The effect of friction on the flow of steam through a nozzle is to decrease the __________ of steam.
Wetness
Mass flow rate
Both 'a' & 'b'
Neither 'a' nor 'b'
Out of the following, the __________ pipe has the least corrosion resistance.
Mild steel
Copper
Cast iron
Wrought iron
__________ are normally subjected to sub-zero treatment.
Highly stressed parts
Gauges or precision parts
Cold rolled sheets
Non machinable materials
The wet bulb temperature is lower in dry air than in wet air at the same temperature. A dry bulb thermometer registers a higher temperature than a wet bulb thermometer except at __________ percent relative humidity.
0
100
50
None of these
Blow off cock is provided in steam boiler to
Guard the boiler in case of abnormal rise in steam pressure
Drain out water and sludge during its repair
Regulate the supply of water in boiler
Put out the fire in the furnace when the water level in the boiler falls to unsafe limit
Otto cycle used in spark ignition petrol engines is also known as the constant __________ cycle.
Volume
Pressure
Heat
None of these
Work required for compression of a gas contained in a cylinder is 7000 kJ. During compression, heat interaction of 3000 kJ causes the surroundings to be heated. Internal energy change of the gas during the compression is __________ kJ.
+4000
-4000
10000
-10000
Catalyst used in the catalytic converter employed in automobiles to convert CO into CO2 and for complete oxidation of un-burnt hydrocarbons is
Nickel
Cobalt
Vanadium
Platinum
The activity of pure hydrogen gas at 1000°C and 5 atm pressure
Is always less than 1
Is always greater than 1
Can be 5
Depends on the choice of the standard state
The difference between gross & net calorific values of fuel is due to the
Sensible heat carried away by the flue gases
Heat carried away by the steam from the moisture content of the fuel
Heat lost by radiation
Heat carried away by steam from the combustion of hydrogen in the fuel
The product (s) of roasting of a sulphide ore is (are)
Oxide only
Sulphate only
Oxide and sulphate
Dependent on temperature and partial pressure of oxygen & sulphur dioxide
To counteract the bad effects of strain hardening on a cold formed part, it must be
Tempered
Normalised
Annealed
Hardened
Catalyst used in the 'catalytic converter' employed in automobile exhaust line for complete combustion/oxidation of carbon monoxide, nitrogen oxides and hydrocarbons is
Alumina
Platinum
Vanadium pentoxide
Iron oxide
Identify the correct statement with reference to the extractive metallurgy of aluminium.
The electrolyte consists of molten Na3AlF6 with approximately 1 to 8% Al2O3
Approximately 80% of the aluminium deposited on the cathode comes from cryolite
Sodium is deposited along with aluminium, but is immediately vaporised
Anode effect sets in when the cryolite concentration goes below 40%.
The temperature at which the magnetic property of iron disappears (i.e., it becomes non-magnetic) and its electrical conductivity & specific heat also changes, is called the 'Curie point', which is __________ °C.
768
908
1400
1539
Which of the, following is not associated with the functioning of a petrol engine?
Compression ignition system
Spark plug
Carburettor
Otto cycle
Principal alloying element in Elinvar (used for making hair springs for watches) is
Copper
Aluminium
Nickel
Zinc
The most important consideration, while designing the refrigeration system of an aircraft is that the refrigeration system
Is as light as possible
Has very high C.O.P.
Employs minimum quantity of refrigerant
Consumer minimum horse power
Magnetic permeability of iron is increased by its
Decarburising
Alloying with cobalt
Purification
Alternate heating & cooling
Projection welding & stud welding is categorised as the __________ welding.
Pressure
Thermit
Resistance
Arc
A 2 kg object weighs 1.8 kgf on a spring balance. The value of 'g' at that location in m/sec2 is
8.82
9.81
10.88
0.95
__________ cannot increase the fatigue strength of a material.
Grain refining
Grain coarsening
Surface hardening
Shot peening
According to maximum shear stress failure criterion, yielding in material occurs, when the maximum shear stress is equal to __________ times the yield stress.
0.5
2
√2
√3/2