The approximate height of a blast furnace having a useful volume of 2000 m3 is about __________ metres
25
35
55
75
Correct Answer :
C. 55
Related Questions
Which of the following is an example of stress corrosion?
Season cracking of brass
Caustic embrittlement of steel
Both (A) & (B)
Neither (A) nor (B)
Which of the following is not a charge material for cupola?
Limestone
Iron scrap
Iron ore
Pig iron
Which of the following varies as the square root of oil pressure during atomisation of fuel oil through a pressure jet burner?
Output & fineness
Velocity
Both (A) & (B)
None of these
Particle nature of cathode rays is proved due to the fact that they
Travel in a straight line
Get deflected by magnetic electric field
Produce fluorescence
Heat the exposed material
The ratio of thermal & electrical conductivity is same for all the metals at the same temperature; and at around room temperature, this ratio is proportional to(where, T = absolute temperature, °K)
T
1/T
T2
1/T2
__________ of austenite decreases the hardenability in steel.
Fine grains
Coarse grains
Homogeneity
Dissolved elements (except cobalt)
__________ is the hardest material out of the following.
Boron carbide
Tungsten carbide
Hardened steel
Silicon carbide
Pick out the wrong statement.
Seam welding, projection welding & spot welding are the classification of electrical resistance welding
Electrode tip in spot welding is of copper and the tip diameter should be equal to t (where, t = plate thickness to be welded)
In spot welding, two pieces to be joined are overlapped and placed between two electrodes
Mild steel sheet cannot be spot welded
Addition of small amount of __________ to grey cast iron is done to produce nodular grey cast iron.
Manganese
Phosphorous
Magnesium
Chromium
Gratings is associated with the measurement of
Linear displacement
Concavity/convexity
Surface texture
Flatness
What is the critical radius of insulation (cms) for a metallic cylinder, if the convective heat transfer co-efficient with the ambient atmosphere is 5 W/m2. °K? Thermal conductivity of metal and insulation material are 40 and 0.1 W/m.°K respectively.
2
8
10
40
Thermal efficiency of an internal combustion engine is around __________ percent.
8
35
65
80
Silicon percentage in the silicon steel used for electrical appliances/equipments is
0.3-0.4
12-14
3-4
20-25
The escape velocity of a body on earth which is independent of its mass is about __________ km/second.
3
7
11
15
Pearlite comprises of
87% cementite & 13% Fe
87% ferrite & 13% cementite
93.33% ferrite & 6.67% C
87% ferrite & 13% C
A furnace is made of a refractory brick wall of thickness 0.5 metre and thermal conductivity 0.7 W/m.°K For the same temperature drop and heat loss, this refractory wall can be replaced by a layer of diatomaceous earth of thermal conductivity 0.14 W/m.K and thickness __________ metre.
0.01
0.1
0.25
0.5
In the diving apparatus, helium is used along with oxygen, because it is
Easily available
Not soluble in blood at high pressure
Lighter than nitrogen
Completely miscible with oxygen
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
Shrinkage allowance on pattern is provided to compensate for shrinkage when the
Metal changes from liquid state to solid state at freezing temperature
Solid phase temperature drops from freezing temperature to the room temperature
Liquid metal temperature drops from pouring temperature to room temperature
Liquid metal temperature drops from pouring temperature to freezing temperature
Heat transfer by __________ is almost absent in case of fluidised bed drying operation.
Radiation
Conduction
Convection
Both (B) & (C)
The trace metal present in insulin is
Cu
Zn
Fe
Ni
The temperature at which ferromagnetic material can no longer be magnetised by the outside forces, is termed as the
Critical point
Curie temperature
Inversion temperature
Eutectic temperature
Cold heading or upsetting is categorised as the __________ process.
Extrusion
Bending
Rolling
Forging
Aluminium is extracted from
Chalcocite
Bauxite
Galena
None of these
The ratio of the shear stress to the principal stress on a principal plane is
0
1
1/2
1/3
Silicon crystal can be converted to p-type semiconductor by doping with
Phosphorous
Nitrogen
Carbon
Boron
Which of the following metals reacts violently with water?
Mercury
Sodium
Calcium
Magnesium
In an eutectic system, two elements are completely
Soluble in solid state
Insoluble in liquid state
Insoluble in both solid & liquid state
Soluble in liquid state
Moist air is cooled along the line of constant __________ , when it is passed over a cold & dry cooling coil, such that no condensation occurs?
Enthalpy
Relative humidity
Wet bulb temperature
Dew point temperature
Minimum safe distance between two liquid fuel storage tanks is equal to (where, H = height of the tank)
H
H/2
H/4
H/6