Section 1 Flashcards
Which one of the following is incombustible ?
A. H2
B. CCl4
C. C2H2
D. S
B. CCl4
The softness or hardness of a grinding wheel depends upon the type & amount of bonding material used. For general purpose cutter grinding __________ grinding wheel is normally used.
A. hard
B. soft
C. silicon carbide
D. aluminium oxide
D. aluminium oxide
Tin based white metals are used, where bearings are subjected to
A. high pressure & load.
B. low pressure & load.
C. high temperature.
D. large surface wear.
A. high pressure & load.
Friction factor for fluid flow in pipe does not depend upon the
A. pipe length.
B. pipe roughness.
C. fluid density & viscosity.
D. mass flow rate of fluid.
A. pipe length.
All of the following alloying elements of steel increases hardness but sacrifice ductility, except
A. nickel
B. vanadium
C. molybdenum
D. chromium
A. nickel
The following type of bonding is strongly directional in solids.
A. Vander Waal’s
B. Ionic
C. Metallic
D. Covalant
D. Covalant
Fog is an example of colloidal system of
A. solid dispersed in gas.
B. solid dispersed in liquid.
C. liquid dispersed in gas.
D. gas dispersed in liquid.
C. liquid dispersed in gas.
Chromium molybdenum steel can not be welded using __________ welding.
thermit
electrical resistance
oxy-acetylene
any of these
electrical resistance
Speisses is a mixture of the following:
Arsenides of heavy metals.
Antimonides of heavy metals.
Arsenides & antimonides of heavy metals.
Iron, cobalt and nickel.
Arsenides of heavy metals.
Auto collimator is used to check
flatness
angle
rotor balancing
roughness
angle
In troposphere (the weather domain), the temperature ‘t’ at height ‘h’ above the sea level in metres is given by (where, temperature at sea level is 15°C and t is in °C.)
t = 15 - 0.0065 h
t = 15 + 0.0065 h
t = 0.0035 h - 15
t = 15 - 0.0035 h
t = 15 - 0.0065 h
A high pressure boiler generates steam at a pressure greater than __________ kg/cm2 .
10
30
50
80
80
Evaporative cooling process employs a combination of cooling and humidification in which the
sensible heat is added.
sensible heat is removed and the latent heat is added.
latent heat is removed.
sensible heat is added and latent heat is removed.
sensible heat is removed and the latent heat is added.
Which of the following is not an explosive ?
TNT
CMC
RDX
Lead azide
CMC
Maxwell’s thermodynamic relations applies to the
chemical systems in equilibrium.
mechanical systems in equilibrium.
irreversible thermodynamic processes.
reversible thermodynamic processes.
chemical systems in equilibrium.
Annealing ofwhite cast iron produces __________ iron.
grey
nodular
malleable
spheroidal
malleble
Resistance of an electrical conductor is proportional to its (where, l = length and A = cross-sectional area of the conductor)
A
l
A2
both ‘a’ & ‘b’
both ‘a’ & ‘b’
A solar cell converts the sunlight directly into __________ energy.
thermal
electrical
mechanical
chemical
electrical
If a nuclear reactor produces more fissile nuclear fuel than it consumes, then it is called a __________ reactor.
critical
breeder
fertile
heterogenous
breeder
Wrought iron is never shaped by
casting
cold working
forging
welding
casting
Powder metallurgy process does not make metal powder by
atomisation
grinding/milling
hammering
electrolytic deposition
hammering
In the blast furnace, incorporation of water vapour in the blast gives the following effect.
Increases the reducing potential of the gas.
Increases the flame temperature.
No significant change occurs.
Increases the hydrogen content in the metal.
Increases the reducing potential of the gas.
Pick out the wrong statement.
A ferromagnetic material becomes paramagnetic above the ‘Curie temperature’.
Permanent magnets are made of hard materials, whereas electromagnets require soft magnetic materials.
Soft magnetic materials (e.g., pure iron) have higher permeability and low hysterisis loss and coercive forces.
Tungsten steel and alnico are not hard magnetic materials.
Tungsten steel and alnico are not hard magnetic materials.
The usual energy consumption in electric arc furnace steel making is __________ KWh/ton of steel.
60 - 100
400 - 700
1200 -1500
2000 - 2300
400 - 700
Maximum permissible air velocity in pipelines is about __________ metre/second.
5
10
20
40
10
Area under the stress-strain curve upto the __________ is referred to as the modulus of resilience.
yield strength
elastic limit
proportional limit
maximum point
proportional limit
__________ is the hardest oxide and is hence used where high wear resistance at high temperature is required.
Beryllia
Zirconia
Alumina
Magnesia
Alumina
Titanium alloys are welded using the Following process:
TIG welding.
Submerged arc welding.
Butt welding.
Electron beam welding.
TIG welding.
An alloy of Fe - 0.4 % C is
cast iron.
hypo-eutectoid steel.
hyper-eutectoid steel.
eutectoid steel
hypo-eutectoid steel.
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
lead
In extrusion of metals, which of the following statement is true ?
speed of the extruded material is same as that of ram speed.
Redundant work is a function of the die angle.
Relative motion between the billet surface and the container wall is always present.
Hollow ram is used for indirect extrusion.
Hollow ram is used for indirect extrusion.
Nuclear fission of one atom of uranium-235 produces the energy equivalent to about __________ MeV.
20
200
500
1000
200
Which of the following parameters is not responsible for the heat loss from a hot steam carrying bare pipe surface located in a room without fans ?
Emissivity of pipe surface.
Diameter & length of the pipe.
Temperature of hot pipe surface & that of air in the room.
none of these.
none of these.
Machinability of hard alloys and tool steels is improved by
spherodising
annealing
tempering
normalising
annealing
Transformation range for ferrous material is the temperature interval during which __________ is formed during its heating.
cementite
austenite
martensite
pearlite
austenite
Maximum amount of thermal radiation is emitted at all wavelengths at any specified temperature by a/an __________ body.
grey
black
opaque
white
grey
In condensers used in thermal power plants, steam is normally used in shell side and cooling water on the tube side, because of the reason that
A. compared to the mass flow rate of cooling water, the rate of condensation of steam is invariably smaller.
B. maintaining vacuum on tube side is more difficult than that on the shell side.
C. water velocity can be increased conveniently to increase the overall heat transfer co-efficient because of its lower specific volume compared to steam.
D. condenser can act as a storage unit for condensed steam.
C. water velocity can be increased conveniently to increase the overall heat transfer co-efficient because of its lower specific volume compared to steam.
Cobalt - 60 is used as a source of __________ in medical therapy & industrial radiography.
X-rays
γ-rays
α-rays
β-rays
γ-rays
Absolute zero pressure can be attained at a temperature of
0°C
50°K
0°R
none of these
0°R
The product out from a cupola is called
wrought iron
pig iron
cast iron
none of these
cast iron
Nusselt number is related to Grashoff number (Gr) in turbulent & laminar flow respectively, in respect of free convection over a vertical flat plate as
Gr0.25, Gr
Gr0.25, Gr0.33
Gr, Gr0.25
Gr0.33, Gr0.25
Gr0.25, Gr
If the demand for an item is trebled and the order cost is reduced to one third, then the economic order quantity
is trebled.
remains unchanged.
decreases by a factor of 3.
decreases by a factor of 1/3.
remains unchanged.
Copper deposits are found in India at the following location:
Kudremukh
Kolar
Khetri
Ramagundam
Khetri
Electrical conductivities of semi-conductors are of the order of __________ ohm/cm.
10^-3
10^3
10^-15
l0^15
10-3
Corrosion of metals can not be prevented by its
tempering
chromising
aluminising
alloying
tempering
Transition from laminar to turbulent zone in free convection heat transfer is governed by the critical value of
Grashoff number.
Grashoff number & Reynolds number.
Reynolds number.
Grashoff number & Prandtl number.
Grashoff number & Prandtl number.
The most economical channel section for the fluid flow is the one for which the discharge is maximum for a given cross-sectional area. Vertical velocity distribution in an open channel for laminar flow can be assumed to be
parabolic
hyperbolic
straight line
none of these
parabolic
Energy of the sun arises mainly from __________ reactions.
fusion
fission
combustion
none of these
fusion
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
Stud
Sudden fall of atmospheric pressure by a large amount is an indication of the
rain
cold wave
storm
fair weather
storm
