Temperature of hot gases flowing in a pipe is measured by a thermocouple inserted in the thermal well. The thermal well made of __________ will facilitate the most accurate measurement of the temperature.
Copper
Steel
Aluminium
Brass
Correct Answer :
A. Copper
Related Questions
Change in volume of metals from absolute zero temperature to their melting points is
Almost same for all metals
Different for different metals
Less for low melting point metals
Less for high melting point metals
Out of the following __________ iron has the best capability to bear sudden & excessive shocks.
White
Cast
Wrought
Pig
Air/fuel ratio by weight for combustion of methane with theoretical quantity of air will be about
9 : 1
17 : 1
23 : 1
29 : 1
__________ is the most suitable lubricant for drawing mild steel wires?
Kerosene
Water
Sodium stearate
Lime water
Case hardening is not done by
Nitriding
Hot dipping
Electroplating
Both b & c
The effect of friction on the flow of steam through a nozzle is to decrease the __________ of steam.
Wetness
Mass flow rate
Both 'a' & 'b'
Neither 'a' nor 'b'
Atomic __________ is a whole number for an element.
Number
Weight
Radius
None of these
Brinell Hardness Number (BHN) for talc is approximately in the range of
1-5
20-30
100-150
200-250
When the wavelength of incident X-rays increases, the angle of diffraction
Decreases
Increases
Remain constant
Shows no systematic variation
__________ is the process of coating the surface of steel with aluminium oxide, thereby imparting it increased resistance to corrosion & oxidation upto a temperature of 700°C.
Veneering
Galvanising
Electroplating
Calorising
A solid aluminium ball, when quenched in a water bath maintained at 40°C, cools down from 550°C to 450°C in 20 seconds. The expected temperature of the ball after next 20 seconds may be about __________ °C.
370
340
320
300
Water hammer is caused in steam carrying pipelines, because of
Partial condensation of steam
Vibration of the pipeline
High degree of superheat of steam
Its exposure to torrential rain
Coarse grained steels have
Low toughness
No tendency to distort
High density
Very high toughness
Normalising of an object does not
Refine coarse grain structure obtained during hot working
Improve ductility
Improve yield strength
Improve mechanical properties
Which of the following pairs is not correctly matched?
Uranium - 233 : Fertile material
Binding energy : Mass defect
Scattering: Absorption cross-section
Number of nucleons : Mass number
Percentage of argon (by volume) in dry atmospheric air is about
0.09
0.3
0.57
0.94
__________ of grey cast iron produces white cast iron.
Tempering
Rapid heating
Rapid cooling
Slow cooling
Alumina, silica, lime and iron oxide are the basic raw material for the manufacture of Portland cement. The component of Portland cement which first hardens is
'Cryogenics' is concerned with the generation & use of low temperature in the range of
0°K to 123°K
0°C to - 123°C
0°C to - 273°C
0°K to 273°K
Shampoos are commercially not available in the form of
Powder
Gaseous mixture
Solution
Emulsion
Factor of safety in machine design is defined as the ratio of ultimate stress to __________ stress.
Working
Bearing
Yield
None of these
Nusselt number is related to Grashoff number (Gr) in turbulent & laminar flow respectively, in respect of free convection over a vertical flat plate as
Gr0.25, Gr
Gr0.25, Gr0.33
Gr, Gr0.25
Gr0.33, Gr0.25
Which of the following is the most suitable abrasive for grinding high tensile strength materials?
Silicon carbide
Corundum
Aluminium oxide
Boron carbide
The most abundant metal present in the earth's crust is;
Iron
Copper
Titanium
Aluminium
Neutrons are present in all atoms except that of
He
C
H
Ar
For infinite parallel planes having emissivities ε1 & ε2, the interchange factor for radiation from surface 1 to surface 2 is given by
A high pressure boiler generates steam at a pressure greater than __________ kg/cm2.
10
30
50
80
The cooling rate required to freeze 1 ton of water at 0°C into ice at 0°C in 24 hours is __________ BTU/hr.
100
200
1000
2000
Which of the following is the correct nature of shear stress distribution along the cross section in a horizontal circular pipe under steady state fluid flow condition?
Pick out the wrong statement.
Ductile fracture of a stressed material, which exhibits a large plastic deformation is commonly caused by the formation and coalescence of voids in the necked region
Brittle fracture is caused by the propagation of pre-existing cracks in the material and involves minimum plastic deformation
Fatigue fracture of a material is always brittle in nature and takes place due to the existence of line imperfections
Brittle materials are generally tested in tension