__________ furnace is generally used in the non-ferrous foundries.
Direct arc
Indirect arc
Resistance
Induction
Correct Answer :
B. Indirect arc
Related Questions
Vibration upto 100 kilo hertz can be most accurately measured by a __________ type accelerometer.
Preloaded spring
Piezoelectric
Bonded strain gauge
None of these
The minimum temperature to which the water can be cooled in a cooling tower is the __________ temperature of air.
Ambient
Dry bulb
Dew point
Wet bulb
Which of the following materials has the poorest electrical conductivity?
Carbon
Aluminium
Silver
Stainless steel
The only suitable method for hardening the low carbon steel is case hardening. Which of the following is a case hardening process?
Cyaniding
Sherardizing
Spheroidising
None of these
Highest cutting speed is achieved by the __________ tool material.
High speed steel
Carbide
Cast alloy
Plain carbon steel
The property of material, by which a given amount of energy is absorbed by it without plastic deformation, is called the
Resilience
Toughness
Ductility
Impact strength
Hot working of lead is carried out at
75°C
373°K
150°C
Room temperature
Pick out the wrong statement.
Weldability of high carbon steel is poorer compared to low carbon steel
Invar is a magnetic alloy
Magnetic permeability of the diamagnetic material is less than one
Martenistic transformation never goes to completion (i.e., 100%) at room temperature
Euler number is defined as the ratio of inertia force to __________ force.
Pressure
Elastic
Gravity
Viscous
Pick out the correct statement about the condensation.
Filmwise condensation gives a lower heat transfer rate than the dropwise condensation
Suitable coating or vapour additive is used to promote film wise condensation
If a condensing liquid does not wet the surface dropwise, even then condensation will take place on it
Reynolds number of condensing liquid is based on its mass flow rate
Which of the following is not a ferromagnetic material?
Nickel
Cobalt
Aluminium
Iron
Which of the following if present in iron ore, enhances its value?
Alumina
Alkali oxide
Lime & Magnesia
None of these
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
Limestone is added in the blast furnace (during pig iron manufacture) to
Form slag by combining with impurities
Supply heat by undergoing exothermic reaction with impurities
Reduce the coke consumption
Reduce slag viscosity
The refractory lining of the bottom in a basic electric arc furnace is made of
Silica
Alumina
Magnesia
Fireclay
Which of the following is resistant to the action of both heat & chemicals?
Borosilicate glass
Silica glass
Soda lime glass
None of these
Out of the following substances, one ton of __________ will store the maximum heat for a rise of 30°C in temperature.
Steel
Lignite
Water
Lime stone
Cassiterite is an ore of
Tin
Lead
Molybdenum
Chromium
The phenomenon occurring during explosion of a hydrogen bomb is
Nuclear fission
Nuclear fusion
A combination of both nuclear fission & fusion
None of these
In case of condensers & evaporators operating under given terminal conditions, LMTD (logarithmic mean temperature difference) for counter flow as compared to that for parallel flow is
More
Less
Equal
Much more
__________ is not a case hardening process.
Carburising
Nitriding
Cyaniding
Annealing
__________ property of a material is determined by the Herbert Pendulum device.
Hardness
Tensile
Toughness
Compressive
Tesla metre per ampere (T. m/A) is the unit for the measurement of
Magnetic susceptibility
Magnetic moment
Permeability of free space
Flux density
The main constituent of bones is
CaF2
Ca3(PO4)2
CaCO3
CaCl2
Which of the following metals is not subjected to electrolytic refining/purification?
Copper
Zinc
Tin
Aluminium
Dew point temperature always gives an indication of the __________ of the moist air.
Dryness
Moisture content
Coolness
Latent heat
Pick out the wrong statement.
Both annealing and normalising release the internal stresses of the material besides improving the mechanical properties
Low carbon steel does not respond to the heat treatment for hardening of the material, hence it is subjected to case hardening or surface hardening processes like cyaniding, carburising, nitriding etc., which produces high carbon outer layers resulting in increase of surface hardness
Induction hardening and flame hardening techniques are also used for surface hardening
Martempering of a material is a hardening process
Young's modulus of a material is the measure of its
Stiffness
Malleability
Creep resistance
Tensile strength
Volume of blast furnace slag is about __________ times the volume of hot metal (pig iron) of the same weight
1.5
3
5
7
Pearlite comprises of
87% cementite & 13% Fe
87% ferrite & 13% cementite
93.33% ferrite & 6.67% C
87% ferrite & 13% C