Steel & cast iron pipes are produced by __________ casting.
Slush
Die
Investment
True centrifugal
Correct Answer :
D. True centrifugal
Related Questions
Which of the following alloying elements is present in maximum percentage in high speed steel?
Molybdenum
Chromium
Tungsten
Vanadium
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
Addition of __________ to steel does not impart hardness.
Nickel
Copper
Chromium
Silicon
In a counter flow heat exchanger, hot fluid enters at 170°C & leaves at 150°C, while the cold fluid enters at 50°C & leaves at 70°C. The arithmetic mean temperature difference in this case is __________ °C.
20
60
120
∞
The phenomenon occurring during explosion of a hydrogen bomb is
Nuclear fission
Nuclear fusion
A combination of both nuclear fission & fusion
None of these
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.
Hard
Soft
Silicon carbide
Aluminium oxide
Corona discharge is related to the operation of a/an
Induction motor
Electrostatic precipitator
Fast breeder reactor
Magneto hydrodynamic generator (MHD)
Which of the following terminology is used for the temperature at which new grains are formed in a metal?
Eutectic temperature
Lower critical temperature
Recrystallisation temperature
Upper critical temperature
Brinell Hardness Number (BHN) for talc is approximately in the range of
1-5
20-30
100-150
200-250
Case hardening of a material is
Followed by tempering or carburising
Preceded by its tempering
Done to get a soft ductile interior with a very hard surface
Carried out to get extreme hardness in its core
Atomic __________ is a whole number for an element.
Number
Weight
Radius
None of these
For infinite parallel planes having emissivities ε1 & ε2, the interchange factor for radiation from surface 1 to surface 2 is given by
Pick out the correct combination about the role of various additives used in polymers.
Plasticiser: increases the polymer strength
Heat stabiliser: increases the maximum service temperature
Fillers: Does not affect the property of polymer but increases its weight
Lubricants: increases the flexibility of polymers
The materials which fracture even at small strains are termed as brittle, while those materials which exhibit an appreciable deformation before failure are termed as
Rigid
Tough
Ductile
Plastic
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
Yield strength of a polycrystalline metal with an average grain size d, is proportional to
d1/2
d-1/2
d
d-1
The bank of tubes located at the back of the domestic refrigerators are the __________ tubes.
Refrigerant cooling
Evaporator
Condenser
Throttling
Heat release during phase change is observed in case of a/an
Boiler
Condenser
Evaporator
All (A), (B) & (C)
Air/fuel ratio on molar (volume) basis for combustion of methane with theoretical quantity of air with be
9.5 : 1
12.5 : 1
15.5 : 1
18.5 : 1
An example of unsteady non uniform flow is the flow of liquid under pressure through a
Tapering pipe at constant flow rate
Tapering pipe at either decreasing or increasing flow rate
Long pipeline of constant diameter
None of these
The activity co-efficient of the solute in a dilute solution
Decreases with the increase of concentration of the solute
Increases with the increase of concentration of the solute
Remains constant
Is unity at infinite dilution
X-rays are
Positively charged
Negatively charged
Neutral
Of higher wavelength than visible light
Annealing of white cast iron produces __________ iron.
Grey
Nodular
Malleable
Spheroidal
In TIG welding, thoriated tungsten electrodes are used, because it
Has higher current carrying capacity
Has better electron emissivity
Is stronger than ordinary tungsten
Is easy to prepare
__________ is not used as the control rod material in a nuclear reactor.
Cobalt
Hafnium
Cadmium
Boron
Metal shots used in shot blasting are made of
Stellite
Steel
Bronze
Lead
Euler number is defined as the ratio of inertia force to __________ force.
Pressure
Elastic
Gravity
Viscous
A thin, flat & square plate measuring 2 m × 2 m is freely hanging in ambient air at 25°C. It is exposed to the solar radiation falling on one side of the plate at the rate of 500 W/m2. The plate temperature will remain constant at 30°C, if the convective heat transfer co-efficient is __________ W/m2 °C.
50
100
150
200
The main charge in blast furnace is usually
Iron ore & coke
Iron ore, coke & air
Limestone, coke & iron ore
Limestone, sand & iron ore
Speed of a submarine in deep sea & that of an aeroplane is measured by a/an
Pitot tube
Hot wire anemometer
Rotameter
Stroboscope