Which of the following is not the commercial name of poly-methyl-methacrylate (PMMA)?
Styrofoam
Lucite
Perspex
Plexiglass
Correct Answer :
A. Styrofoam
Related Questions
Energy to be supplied to the radioactive nucleus for the emission of a neutron is __________ MeV.
0.8
7.8
200
10000
Laser welding is widely employed in the __________ industries.
Electronic
Structural
Process
Heavy
Which of the following forces does not act on a fluid at rest?
Viscous force
Gravity force
Hydrostatic force
Surface tension force
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
A particle is settling in a liquid under Stokesian conditions. The free falling velocity of the particle is proportional to
√(Particle diameter)
Particle diameter
(Particle diameter)2
(Particle diameter)3
Satellites burn off during re-entry to earth's atmosphere, because of the
Combustion with air
Gravitational pull by earth
Friction with earth's atmosphere
Loss in weight of the satellite
Out of the following the refractive index is the highest for
Glass
Diamond
Brine
Kerosene
Maximum permissible sulphur content in steel is __________ percent.
0.015
0.055
0.505
0.805
Nusselt number is related to the Reynolds number (Re) in turbulent & laminar flow respectively as
Re0.5, Re0.8
Re0.8, Re-0.5
Re0.8, Re0.5
Re-0.8, Re0.5
Percentage of differential pressure lost in a Venturimeter with a tapering of 15° may be about
1
10
25
50
The most commonly used moderator in nuclear power plants is
Graphite
Light water
Heavy water
Beryllium
Addition of __________ to steel does not impart hardness.
Nickel
Copper
Chromium
Silicon
Load cells used for the measurement of weight has
Compact & rugged construction with an accuracy of 0.1 to 1%
No moving parts and incurs negligible deflection under load
Provision of thermal compensation and is hermetically sealed
All 'a', 'b' & 'c'
The same volume of all gases is representative of their
Specific gravities
Densities
Gas characteristic constants
Molecular weights
Most important property of steels for use in automobile bodies is the
Formability
Yield strength
Toughness
Resilience
Gantt charts are used for streamlining the
Inventory control
Production schedule
Sales forecasting
Quality control
__________ of air does not increase with increase in temperature.
Density
Thermal diffusivity
Viscosity
Thermal conductivity
The unit of gc is
lbm/lbf. ft/sec2
lbf/lbm. ft/sec2
ft/sec2
lbm/lbf. sec2/ft
'Flare tower' used in industry is meant for
Venting off (after burning) the excess inflammable/toxic gases at high pressure
Absorbing the pollutant gases from the furnace exhaust
Cooling of furnace exhaust gases
None of these
Shaft/rotor speed is most accurately measured by a
Frequency counter
Tachometer
Strobometer
Speedometer
Ultimate strength in tension as compared to that in shear for steel is
Half
One third
One and half times
One fourth
The following thermocouple may be used for measuring temperature upto 1873°K.
Chromel-alumel
Copper-constantan
Platinum-platinum rhodium
Iron-constantan
With increase in impurities in metals, their corrosion resistances
Increase
Decrease
Remain same
May increase or decrease; depending on the type of metal
Calorific value of __________ are almost same.
Lignite & anthracite coal
Lignite & coal gas
Petrol & diesel
Coal gas & natural gas
Which of the following phenomenon/ phenomena is/are diffusion controlled?
Dislocation climb
Cross-slip
Twinning
Recrystallisation
Which of the following is the most suitable abrasive for grinding high tensile strength materials?
Silicon carbide
Corundum
Aluminium oxide
Boron carbide
Out of the following, which will fracture most readity, when hit with a hard hammer?
Brass
Bronze
German silver
Cast iron
For preparation of porous bearings by powder metallurgy, preferred particle shape is
Spherical
Nodular
Irregular
No preferred shape
Work hardenable alloy steel used to make the bucket wheel excavators, blades of bulldozers and other earth moving equipments contain iron, carbon and
Manganese
Silicon
Nickel
Chromium
High endurance limit of carburised machine parts is because of the fact that carburisation
Suppresses any stress concentration produced in the parts
Enhances the yield point of the material
Introduces a compressive layer on the surface
Produces a better surface finish