Name the safety device used to protect the boiler, when the water level falls below a minimum level.
Blow down valve
Blow off cock
Fusible plug
Safety valve
Correct Answer :
C. Fusible plug
Related Questions
Main constituent of bone ash is
Ammonium phosphate
Calcium phosphate
Animal charcoal
Ammonium sulphate
Unit of viscosity in CGS system is
Speed of a submarine in deep sea & that of an aeroplane is measured by a/an
Pitot tube
Hot wire anemometer
Rotameter
Stroboscope
Which of the following is not categorised as the ore agglomeration process?
Nodulising
Pelletising
Balling
Briquetting
Referring to the periodic table of elements, it is found that with increasing atomic number. The atomic size in the same
Period increases
Period decreases
Group increases
Both 'b' & 'c'
While the thermosetting polymers are amorphous in nature, the thermoplastic polymers are either amorphous or crystalline. The crystalline polymers are characterised by the
Low impact strength
High flexibility
Better finish and surface appearance
High plastic deformation
Steel containing low percentage of nickel, chromium & tungsten are termed as the __________ steel.
Wrought
Tool
Alloy
Plain carbon
__________ is the most important element, which controls the physical properties of steel.
Manganese
Silicon
Carbon
Vanadium
Which of the following relationships is correct for relating the three elastic constants of an isotropic elastic material (where, E = Young's modulus, G = Modulus of rigidity or shear modulus v = Poisson's ratio)?
E = 2G (1 + v)
E = G (1 + v)
E = G (1 + v)/2
E = 2G (1 + 2v)
Materials having resistivity ranging from 1 to 100 ohm. cm is termed as
Conductor
Insulator
Semi-conductor
None of these
Dew point temperature always gives an indication of the __________ of the moist air.
Dryness
Moisture content
Coolness
Latent heat
Steel is welded using the __________ flame.
Carburising
Neutral
Oxidising
All (A), (B) & (C)
Pick out the wrong statement.
Molecules with symmetrical arrangements (e.g. CH4 or CCl4) are non-polar
Generally, non-polar compounds are chemically inactive, conduct electricity poorly and do not ionise
Most of the hydrocarbons are non-polar
None of these
In the Bayer's process, bauxite is digested under pressure using
H2SO4
NaOH
NH3
HCl
Secondary hardening in steels arises out of the
Precipitation of fine alloy carbides at high temperatures
Refinement of ferrite grain size by working
Decomposition of retained austenite upon heat treatment
Precipitation of complex inter-metallic upon heat treatment
A common disinfectant used in village wells for disinfection of water is
Free chlorine
Bromine
Iodine
Potassium permanganate
Hardening of steel is not possible, unless it is heated __________ critical point.
Above the highest
Above the lowest
Between the first & second
Between the second & third
Use of economiser in a boiler plant reduces the fuel consumption for steam generation by about __________ percent.
1
10
30
50
Increasing sulphur content in pig iron tends to make it
Soft
Hard
Tough
Ductile & malleable
Function of gear box is to
Reduce the speed
Obtain variable speed
Increase the speed
Produce high torque
Fibre glass is a composite material of
Glass fibre in a polymer matrix
Glass fibre in a metallic matrix
Polymer fibre in a glassy matrix
Both 'b' & 'c'
Energy to be supplied to the radioactive nucleus for the emission of a neutron is __________ MeV.
0.8
7.8
200
10000
A cylindrical rod subjected to a tensile strain within the elastic limit undergoes a volume change. If the volume strain is equal to half the tensile strain, then the Poisson's ratio of the rod is
0
0.33
0.44
0.25
The ability of tool steel to resist softening at high temperatures is termed as __________ hardness.
Red
Extended
Super
Extreme
Which of the following fastening devices has a head at one end and a nut fitted to the other?
Bolt
Stud
Top bolt
None of these
Which of the following is an unconventional source of energy?
Thermal power
Hydroelectric power
Nuclear-fusion power
Solar power
The maximum stress below which a material can withstand an infinite number of cycle of stress, is termed as the
Fatigue strength
Creep strength
Resilience
Endurance limit
The two elements required to form substitutional solid solution should not have
Same crystalline structure
Same valency
Widely differing electronegativity
Same atomic sizes
Lead pencil contains
Graphite
Lead sulphide
Lead
Both (B) & (C)
A material being tested for endurance strength is subjected to the __________ load.
Impact
Completely reversed
Dynamic
Static & dynamic