At the point of boundary layer separation in fluid flow, the
Shear stress is maximum
Velocity gradient is flat
Density variation is maximum
Shear stress is zero
Correct Answer :
A. Shear stress is maximum
Related Questions
An example of unsteady non uniform flow is the flow of liquid under pressure through a
Tapering pipe at constant flow rate
Tapering pipe at either decreasing or increasing flow rate
Long pipeline of constant diameter
None of these
Percentage of differential pressure lost in a Venturimeter with a tapering of 15° may be about
1
10
25
50
Limestone is added in the blast furnace (during pig iron manufacture) to
Form slag by combining with impurities
Supply heat by undergoing exothermic reaction with impurities
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Reduce slag viscosity
Dryness fraction of dry steam is
0
∞
1
0.5
Recrystallisation temperature of steel is __________ °C.
50
300
500
800
For efficient performance of a blast furnace, the extent of reduction of Wustite (FeO) should be
100% indirect reduction
100% direct reduction
50-60% indirect reduction
30-40% indirect reduction
Water hammer is caused in steam carrying pipelines, because of
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Vibration of the pipeline
High degree of superheat of steam
Its exposure to torrential rain
Leakage in a cooking gas cylinder is detected by
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Pouring soap solution on the surface and locating the gas bubbles
Halide torch
Pungent smell of mercaptans present in the gas
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Insoluble in liquid state
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Elimination of brittleness resulting from welding of saw blades is done by __________ of the welded portion.
Annealing
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Baffles provided on the shell side of a shell and tube heat exchanger are meant for
Providing support for the tubes
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__________ of grey cast iron produces white cast iron.
Tempering
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Rapid cooling
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The swift cup test evaluates the following property of a sheet metal.
Stretchability
Drawability
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Chemical composition
Carbon content
Grain size
Alloying elements content
Gross national product (GNP) means the total value of __________ in a country.
Goods produced
Gold reserve
Earning of the citizens
Taxes paid
Thermit welding uses the following energy source.
Electrical energy
Chemical energy
Energy of high velocity electrons
Heat generated by friction
Large diameter reinforced cement concrete (RCC) pipes are generally joined by __________ joint.
Flanged iron
Collar
Flexible
Expansion
Energy to be supplied to the radioactive nucleus for the emission of a neutron is __________ MeV.
0.8
7.8
200
10000
Which of the following are made out of the carbon steel having carbon content of 0.9 to 1%?
Small punches, broaches reamers and springs
Cutlery, screws, rivets and files
Mandrels, twist drills, small lathe tools and razors
Forgings like can shaft, structural steel plate, threading dies and drawing dies
Solute atoms which cause yield point phenomenon in mild steel are/is
Aluminium
Boron
Carbon
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Preheating before welding is done to
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Burn oil & grease sticking to plate surfaces
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Multistage compression of air as compared to single stage compression offers the advantage of
Power saving per unit weight of air delivered
Moisture elimination in the inter-stage cooler
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Less than the wet bulb temperature
More than the wet bulb temperature
More than the dry bulb temperature
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The excess air required for the combustion of pulverised coal is of the order of about __________ percent.
5
15
30
45
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Normalised
Annealed
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Pressure
Heat
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The lightest non-inflammable gas is
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Ar
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Notched bar impact
Tensile
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