Unit of surface tension in S.I. unit is
Watt/m
Joule/
Newton/
Joule/m
Correct Answer :
B. Joule/
Related Questions
Property responsible for the talcum powder to cling to the skin is the
Capillary action
Adhesion
Cohesion
Surface tension
Neutrons are present in all atoms except that of
He
C
H
Ar
Which of the following approaches the ideal gas behaviour most closely?
Wet steam
Saturated steam
Superheated steam
Saturated water
Probability of cavitation occuring becomes very high, when the local __________ resulting in water bubbles formation, which on rupture cause cavitation
Pressure falls below the vapour pressure
Pressure becomes very high
Temperature becomes low
All 'a', 'b' & 'c'
Metallic surveying tapes are made of __________ which has a low co-efficient of expansion & enough strength.
Invar
Hastelloy
Duralumin
Monel metal
The normal stress is the same in all directions at a point in a fluid, only when the fluid
Is at rest & has zero viscosity
Is frictionless
Fluid layer has no motion relative to an adjacent layer of fluid
is incompressible & frictionless
Hydro-cyclone is a
Crusher
wet classifier
Dry classifier
Magnetic separator
The ratio of thermal & electrical conductivity is same for all the metals at the same temperature; and at around room temperature, this ratio is proportional to(where, T = absolute temperature, °K)
T
1/T
T2
1/T2
Reduction in the grain size reduces the __________ of the material.
Fatigue resistance
Tensile strength
Creep resistance
All (A), (B) & (C)
During sensible cooling of air, its wet bulb temperature
Decreases but dew point remains constant
Increases but dew point remains constant
Increases & the dew point decreases
Decreases & the dew point increases
Baffles provided on the shell side of a shell and tube heat exchanger are meant for
Providing support for the tubes
Improving heat transfer
Both 'a' & 'b'
Preventing the fouling of tubes & stagnation of shell side fluid
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
Steel balls are manufactured by
Sintering
Casting
Cold heading
Spinning
The most detrimental impurity in high pressure boiler feed water is
Suspended salt
Dissolved salt
Silica
Turbidity
The kinematic viscosity (in stoke) and the absolute/dynamic viscosity (in poise) are the same for __________ at room temperature.
Air
Water
Mercury
Alcohol
The passage between the nozzle and the __________ is called 'sprue' in case of injection moulding.
Runner
Cylinder
Mold
None of these
Function of fusible plug in a boiler is to
Drain out water and sludge from the boiler during repair
Put off fire in the furnace when water level in the boiler falls to unsafe limit
Guard the boiler in case of abnormal rise in steam pressure
All (A), (B) & (C)
__________ stress cannot be sustained by a fluid in equilibrium.
Shear
Tensile
Compressive
None of these
Wavelength of radiation emitted by a body depends on the __________ of its surface.
Temperature
Area
Nature
All 'a', 'b' & 'c'
The __________ of a double acting reciprocating pump as compared to the single acting pump will be almost double.
Flow output
Head developed
Overall efficiency
Weight
Work study deals with the __________ study.
Time
Motion
Both (A) & (B)
Neither (A) nor (B)
Temperature attained in soldering of metals is about __________ °C.
150-300
400-500
650-800
1000-1100
__________ has a negative co-efficient of linear expansion.
Iron
Copper
Rubber
Nickel
Wrought iron does not have
Uniform strength in all directions
Ability to hold protective coating
High ductility & corrosion resistance
Easily weldable characteristics
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
__________ is the most important element, which controls the physical properties of steel.
Manganese
Silicon
Carbon
Vanadium
Normalising does not __________ of a metal.
Improve machinability & tensile strength
Remove internal stresses
Refine the structure
Remove strains caused by cold working
Heating the Hypo-eutectoid steels to 30°C above the upper critical temperature line, soaking at that temperature and then cooling slowly to the room temperature to form a pearlite & ferrite structure is called
Tempering
Hardening
Annealing
Normalising
The temperature at which the magnetic property of iron disappears (i.e., it becomes non-magnetic) and its electrical conductivity & specific heat also changes, is called the 'Curie point', which is __________ °C.
768
908
1400
1539
Pick out the correct statement
Jet engine can work, where there is no atmosphere
Rocket engines cannot work, where there is no atmosphere
Rocket engines carry oxygen required for the combustion in the form of oxidiser
Jet engines also carry oxidiser