A material being tested for endurance strength is subjected to the __________ load.
Impact
Completely reversed
Dynamic
Static & dynamic
Correct Answer :
B. Completely reversed
Related Questions
__________ is the process used for setting up compressive stresses in the surface of a metal to improve its fatigue strength.
Lancing
Shot peening
Slugging
Spinning
Filler material used in welding should have __________ as compared to the parent metal to be welded.
Lower melting temperature
Same melting temperature
Same composition
Both 'b' & 'c'
A material is capable of resisting softening at high temperature, because of its property termed as
Hot temper
Hot hardness
Fatigue
Creep
Transformer cores are normally made from
Soft ferrites
High purity iron
Grain oriented Fe-Si alloy
Al-Ni-Co alloy
Out of the following, maximum temperature drop for a given heat flow & for the same thickness will be in the case of
Steel
Glass wood
Copper
Fireclay bricks
Powder metallurgy is used to produce
High precision components with complex cavities and sharp features
Components of large size
Porosity free components
Components of such alloys whose constituents do not form alloys readily
The material used for coating the welding electrode is termed as the
Flux
Slag
Protective layer
Binder
__________ is the hardest oxide and is hence used where high wear resistance at high temperature is required.
Beryllium
Zirconia
Alumina
Magnesia
Which of the following properties of a solid is not dependent on crystal imperfection?
Ductility
Semi-conductivity
Melting point
Yield stress
Blast furnace slag is mainly molten
Sand
Magnesium silicate
Calcium silicate
Iron pyrite
__________ property of a material is determined by the Herbert Pendulum device.
Hardness
Tensile
Toughness
Compressive
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
Sand used to stop the green sand from sticking to the pattern is termed as the __________ sand.
Parting
Synthetic
Loam
Dry
Specific gravity of hot metal (pig iron) is __________ times that of the blast furnace slag.
2
3
0.8
6
__________ cannot increase the fatigue strength of a material.
Grain refining
Grain coarsening
Surface hardening
Shot peening
What is the percentage of chromium in 18-4-1 high speed steel?
1
4
18
23
The usual energy consumption in electric arc furnace steel making is __________ KWh/ton of steel.
60 - 100
400 - 700
1200 -1500
2000 - 2300
LVDT used for displacement measurement is a/an __________ transducer.
Passive
Active
Capacitive
None of these
Annealing of white cast iron produces __________ iron.
Grey
Nodular
Malleable
Spheroidal
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
The delivery pressure of boiler feed water pump compared to the boiler steam pressure is
Same
Slightly less
Slightly more
Much more
Inertial forces are obtained, when the elastic forces are multiplied by __________ number.
Mach
Froude
Reynolds
Euler
A steam carrying pipeline is insulated with two layers of insulating materials with the inferior insulation material forming the inner part. If the two insulating layers are interchanged, the heat conducted will
Increase
Decrease
Remain unaffected
May increase or decrease; depends on the thickness of each layer
__________ is the hardest material out of the following.
Boron carbide
Tungsten carbide
Hardened steel
Silicon carbide
Dryness fraction of dry steam is
0
∞
1
0.5
Hot & cold working of material causes its __________ deformation.
Visco-elastic
Isotropic
Elastic
Plastic
Pick out the correct statement.
Hot worked materials are subjected to annealing to remove internal stresses
Annealing of steel hardens it slightly
Normalising of a material induces stresses
Tempering of a material improves ductility & toughness but reduces hardness & brittleness
Propulsion of rocket follows from the
Newton's second law of motion
Newton's third law of motion
Law of projectiles
Archimedes principle
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
Shaft/rotor speed is most accurately measured by a
Frequency counter
Tachometer
Strobometer
Speedometer