Fire refining process is employed in case of
Tin
Copper
Zinc
Aluminium
Correct Answer :
B. Copper
Related Questions
Non-ferrous alloys used for making cutting tools need not have high
Abrasion resistance
Toughness
Red hardness
Cutting speed
Drills are usually made of
Cermets
High speed steel
Alloy steel
Tungsten carbide
In a good rimming steel
Carbon and silicon should be low
Silicon should be low but carbon should be high
Both silicon & carbon should be high
Silicon should be high but carbon should be low
The amount of different substances produced, when the same quantity of electricity is passed through different solutions are proportional to their
Equivalent weight
(Equivalent weight)2
Molecular weight
(Molecular weight)2
Copper deposits are found in India at the following location:
Kudremukh
Kolar
Khetri
Ramagundam
For infinite parallel planes having emissivities ε1 & ε2, the interchange factor for radiation from surface 1 to surface 2 is given by
Calorific value of __________ are almost same.
Lignite & anthracite coal
Lignite & coal gas
Petrol & diesel
Coal gas & natural gas
Which of the, following is not associated with the functioning of a petrol engine?
Compression ignition system
Spark plug
Carburettor
Otto cycle
Circular cross section machine parts which are symmetrical about the axis of rotation are made by hot
Piercing
Spinning
Drawing
Extrusion
Desalination of water
Makes it potable
Makes it non-potable
Means distillation of water
None of these
Increasing the carbon content of steel
Reduces the upper shelf energy
Increasing the ductility transition temperature
Decreases brittleness
Decreases hardness
Sudden fall of atmospheric pressure by a large amount is an indication of the
Rain
Cold wave
Storm
Fair weather
Maximum heat dissipation occurs from a steel wire (k = 0.5 W/m. k) of 15 mm diameter exposed to air (h = 20W/m2 .k), when the insulation thickness is __________ mm.
15
25
10
30
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
To counteract the bad effects of strain hardening on a cold formed part, it must be
Tempered
Normalised
Annealed
Hardened
Pick out the wrong statement.
For a pressure vessel to be classified as 'thin vessel', the ratio of wall thickness to mean radius is less than 0.1
For calculating forces and efficiency of riveted joint, either rivet diameter or rivet hole diameter is used in case of pressure vessel and in structural work
Longitudinal joint is normally made butt joint to maintain the circularity of the vessel
Maximum diameter of the opening provided in a pressure vessel, which does not require any compensation is 200 mm
Which of the following is not a characteristic observed in material failure by fatigue fracture?
Plastic deformation of material does not occur
Initiation of crack from below the surface does not occur
Initiation of crack occurs on the surface of the machine part
Presence of both rough & smooth zone with conchoidal markings in smooth zone of the surface
Hot dipping process is used for coating a low melting point metal (e.g. Pb, Sn, Zn) on iron, steel & copper having relatively higher melting points. Which of the following is not a hot dipping process?
Galvanising
Tinning
Sherardizing
None of these
Filler material used in welding should have __________ as compared to the parent metal to be welded.
Lower melting temperature
Same melting temperature
Same composition
Both 'b' & 'c'
The trace metal present in insulin is
Cu
Zn
Fe
Ni
__________ circuit is most commonly used to measure strain with the help of a strain gauge.
Ballast
Voltage balancing potentiometric
Simple current sensitive
None of these
A solar cell converts the sunlight directly into __________ energy.
Thermal
Electrical
Mechanical
Chemical
Spheroidising of a material is a/an __________ process.
Normalising
Annealing
Tempering
Hardening
Boiling point of water gets lowered at high altitudes (e.g., hills), because
Temperature is low
Atmospheric pressure is low
Atmospheric pressure is high
None of these
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
Transformation range for ferrous material is the temperature interval during which __________ is formed during its heating.
Cementite
Austenite
Martensite
Pearlite
The mechanism which changes the value of manipulated variable in response to the output signal from the control unit is called the
Final control element
On-off control
Floating control action
None of these
Blasting of tri-nitro-toluene (TNT) is done by mixing it with ammonium
Nitrate
Sulphate
Carbonate
Chloride
Titanium is produced by __________ of Ti Cl4.
Electrolytic reduction
Calcium reduction
Magnesium reduction
Thermal dissociation
Hydro-cyclone is a
Crusher
wet classifier
Dry classifier
Magnetic separator