__________ of test specimens is not involved in any hardness testing method.
Fracture
Indentation
Wear
Scratch
Correct Answer :
A. Fracture
Related Questions
Blow off cock is provided in steam boiler to
Guard the boiler in case of abnormal rise in steam pressure
Drain out water and sludge during its repair
Regulate the supply of water in boiler
Put out the fire in the furnace when the water level in the boiler falls to unsafe limit
In connection with corrosion of metals, passivation is the process that
Intensifies deterioration
Changes the composition of the metal
Inhibits further deterioration
None of these
Constituents of stellite are
Zinc, copper & nickel
Cobalt, chromium & tungsten
Zinc, aluminium & nickel
Nickel, cobalt & vanadium
Softening of hardened steel is done by its
Normalising
Tempering
Annealing
Carburising
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
The delivery pressure of boiler feed water pump compared to the boiler steam pressure is
Same
Slightly less
Slightly more
Much more
In Imperial Smelting Process for extraction of zinc, zinc vapour thus produced is quenched in the external condenser by the use of the following:
Jet of water at high pressure
Blast of air
Mixture of water and air
Rain of molten lead
Laser welding is widely employed in the __________ industries.
Electronic
Structural
Process
Heavy
High relative humidity decreases the evaporative process and as the temperature is increased, the relative humidity decreases. The comfort range for human body is the ambient temperature of 22 to 27°C with relative humidity ranging from __________ percent.
5 to 10
15 to 25
45 to 50
75 to 80
Pick out the wrong statement.
The equivalent stiffness of two springs (of equal stiffness 'S') in series is S/2 while in parallel is 2S
For a helical spring, deflection is proportional to D3 (D = mean coil diameter) or d4 (d = wire diameter)
Crushing load or columns is less than the buckling load
Modulus of resilience is proportional to (stress at elastic limit)2
Aluminium is extracted from
Chalcocite
Bauxite
Galena
None of these
The trace metal present in insulin is
Cu
Zn
Fe
Ni
Nitriding of a steel part does not increase its
Grain size
Fatigue limit
Surface hardness
Wear resistance
Rankine cycle comprises of two isothermal and two __________ processes.
Isobaric
Polytropic
Isentropic
None of these
Carbide tipped cutting tools are manufactured by powder metallurgy techniques and have a composition of
90% tungsten carbide and 10% cobalt
70% aluminium oxide & 30% silica
30% nickel, 15% chromium & 55% tungsten
65% tungsten & 35% zirconium
Atomic __________ of an element is a whole number.
Weight
Number
Volume
Radius
X-rays are
Positively charged
Negatively charged
Neutral
Of higher wavelength than visible light
Out of the following, the best material capable of withstanding shock & vibration without the danger of cracking is
Malleable iron
Grey cast iron
Chilled cast iron
White cast iron
Which of the following is not the function of a volute casing provided in a centrifugal pump?
To reduce the head loss in discharge
To increase the pump efficiency
To collect liquid from the periphery of the impeller and to transmit it to the delivery pipe at constant velocity
To increase the pump discharge rate
Fahrenheit and Centigrade scales have the same readings at
-55°
-40°
-33°
-58°
__________ circuit is most commonly used to measure strain with the help of a strain gauge.
Ballast
Voltage balancing potentiometric
Simple current sensitive
None of these
Mho's scale of hardness, which consists of 10 standard minerals is used for the measurement of __________ hardness.
Scratch
Indentation
Dynamic
Rebound
Auto collimator is used to check
Flatness
Angle
Rotor balancing
Roughness
Density in the solid state is slightly less than that in its liquid state, in case of
Carbon dioxide
Water
Mercury
None of these
More than 95% of __________ is present in corundum.
SiO2
Al2O3
CaSiO2
MgO
Lead is added to 60:40 brass primarily to improve
Machinability
Corrosion resistance
Fluidity
Strength
Window panes of aeroplanes are normally made of
Perspex (PMMA)
Teflon (PTFE)
Bakelite (phenol formaldehyde)
Polystyrene
Closeness of packing is maximum in case of __________ crystal lattice.
Face centred
Simple cubic
Body centred
None of these
Ammonia gas can be dried by
PCl5
Quick lime
CaCl2
Concentrated H2SO4
The co-ordination number in simple cubic structure is
4
6
8
12