A steam pipe is intended to be insulated with two layers of insulating materials of different thermal conductivities. For minimum heat transfer to take place
The better insulation material should be put just next to pipe (i.e., inside)
The better insulating material should be put outside
Either of the insulating material could be put on either side
Steam temperature is considered before deciding as to which insulating material is to be put inside (i.e., just next to the pipe)
Correct Answer :
A. The better insulation material should be put just next to pipe (i.e., inside)
Related Questions
'Ice point' is designated on Fahrenheit temperature scale by
0°
32°
62°
212°
Which of the following is not used as a bearing material?
Copper-lead alloys
Babbitts
Bronzes
Cermets
Work done by a/an __________ process is determined by ∫p. dv
Adiabatic
Quasi-static
Isothermal
Isentropic
The most important consideration, while designing the refrigeration system of an aircraft is that the refrigeration system
Is as light as possible
Has very high C.O.P.
Employs minimum quantity of refrigerant
Consumer minimum horse power
The usual energy consumption in electric arc furnace steel making is __________ KWh/ton of steel.
60 - 100
400 - 700
1200 -1500
2000 - 2300
The activity co-efficient of the solute in a dilute solution
Decreases with the increase of concentration of the solute
Increases with the increase of concentration of the solute
Remains constant
Is unity at infinite dilution
The dew point of moist air becomes __________ with decrease in its relative humidity.
Less than the wet bulb temperature
More than the wet bulb temperature
More than the dry bulb temperature
Equal to wet bulb temperature
Transformation range for ferrous material is the temperature interval during which __________ is formed during its heating.
Cementite
Austenite
Martensite
Pearlite
Which of the following contributes maximum as main source of sulphur in the blast furnace charge?
Sinter
Coke
Iron ore
Limestone
Vernier calipers cannot be used to measure the
I.D. & O.D. of the shaft
Thickness of parts
Depth of holes
Clearance between two mating surfaces
Pick out the wrong statement about the machinability of metals. Machinability of a metal
Decreases with increase in strain hardening tendencies
Decreases with increase in hardness, in general
Depend on the composition, microstructure and physical & mechanical properties
Decreases with increases in tensile strength & decrease in grain size
The transition temperature at which all the ferromagnetic materials become paramagnetic materials is termed as the 'Curie temperature'. Its value for cobalt is __________ °C.
768
1127
1359
1480
Which of the following is not the commercial name of poly-methyl-methacrylate (PMMA)?
Styrofoam
Lucite
Perspex
Plexiglass
Which of the following is an unconventional source of energy?
Thermal power
Hydroelectric power
Nuclear-fusion power
Solar power
If a solid is compressed adiabatically in its elastic range, its __________ remains constant
Internal energy
Enthalpy
Entropy
Temperature
High speed steel tools retain their hardness upto a temperature of __________ °C.
500
750
900
1100
Pick out the wrong statement.
Molecules with symmetrical arrangements (e.g. CH4 or CCl4) are non-polar
Generally, non-polar compounds are chemically inactive, conduct electricity poorly and do not ionise
Most of the hydrocarbons are non-polar
None of these
Which of the following is prone to cup and cone fracture?
Cast iron
Soft brass
Round specimen of ductile metal
Flat tensile specimen of ductile metal
Thermit welding uses the following energy source.
Electrical energy
Chemical energy
Energy of high velocity electrons
Heat generated by friction
The life of a ball bearing is inversely proportional to
(Load)1
(Load)2
(Load)3
(Load)0.33
The materials which fracture even at small strains are termed as brittle, while those materials which exhibit an appreciable deformation before failure are termed as
Rigid
Tough
Ductile
Plastic
The thickness of oxide film is y at time t. If 
are the temperature dependent constants, the parabolic law of oxidation is given by
__________ is a non volatile film forming constituent of a paint.
Thinner
Dryer
Drying oil
None of these
While the recrystallisation temperature for pure metals is 0.3 Tm, the same for alloys is equal to __________ × Tm (where, Tm Melting temperature).
0.25
0.45
0.70
0.95
Fatigue limit improvement by over stressing the metal by successively increasing the load is called coaxing. In fatigue failure, the material fails
Below the yield point
Above the yield point
Below the elastic limit
At the elastic limit
With increase in annealing temperature, the following defect density decreases.
Vacancy
Dislocation
Grain boundary
All of these
A form of stress corrosion failure termed as 'season cracking' is generally observed in
Thermosetting polymers
High carbon steels
Brasses
Borosilicate glasses
In a forced draft cooling tower, water is cooled from 95 to 80°F by exposure to air with a wet bulb temperature of 70°F. In this case, the
Range is 15°F
Approach is 10°F
Both (A) & (B)
Neither (A) nor (B)
Cold chisels hammers are made of
High speed steel
High carbon steel
Forged steel
Mild steel
Projection welding & stud welding is categorised as the __________ welding.
Pressure
Thermit
Resistance
Arc