Hydrogen in liquid steels is dissolved
As tiny gas bubbles
In the atomic form
In the ionic form
In the molecular form
Correct Answer :
A. As tiny gas bubbles
Related Questions
The maximum stress below which a material can withstand an infinite number of cycle of stress, is termed as the
Fatigue strength
Creep strength
Resilience
Endurance limit
Viscoelastic behaviour is observed in __________ materials.
Non-crystalline organic polymeric
Ceramic
All crystalline
All amorphous
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'
The elastic strain in copper is due to the
Motion of dislocations
Stretching of atomic bonds
Breakage of atomic bonds
None of the above
Maraging steels derive their strength from the following mechanism:
A fine, highly dislocated and strong martensite
Fine dispersions of inter-metallic of Fe, Ni, Ti etc
Fine dispersions of alloy carbides in a ferrite matrix
Fine dispersions of 
C nucleated on dislocations in austenite
The most important function of a washer is to provide bearing area and washers are normally specified by their hole diameters. The diameter of washer as compared to the nut is
More
Less
Same
More but less than the diameter of bolt
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
The trace metal present in insulin is
Cu
Zn
Fe
Ni
The starting of a car takes time in winter, because the
Octane number of fuel is decreased
Fuel supply for ignition is not sufficient
Vaporisation of the fuel is decreased
Pour point of fuel decreases
Heat transfer by __________ is almost absent in case of fluidised bed drying operation.
Radiation
Conduction
Convection
Both (B) & (C)
Density in the solid state is slightly less than that in its liquid state, in case of
Carbon dioxide
Water
Mercury
None of these
Which of the following is not the commercial name of poly-methyl-methacrylate (PMMA)?
Styrofoam
Lucite
Perspex
Plexiglass
Steel rods are normally used for concrete reinforcement because concrete and steel have almost equal
Tensile strength
Compressive strength
Young's modulus
Thermal co-efficient of expansion
For infinite parallel planes having emissivities ε1 & ε2, the interchange factor for radiation from surface 1 to surface 2 is given by
__________ cannot increase the fatigue strength of a material.
Grain refining
Grain coarsening
Surface hardening
Shot peening
Out of the following, the __________ pipe has the least corrosion resistance.
Mild steel
Copper
Cast iron
Wrought iron
Difference at any instant between the value of the controlled variable and the set point is called the
Deviation
Derivative time
Error ratio
Differential gap
Air standard Otto cycle is more efficient than the diesel cycle for the same
Heat addition & compression ratio
Heat addition & pressure
Compression ratio & pressure
Cylinder dimension & rpm
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
A semi-conductor is damaged & behaves like a conductor, on passing a strong electric current through it, because it heats up the crystals & breaks the covalent bonds resulting in __________ electrons.
Lack of free
Excess of
Decrease in
None of these
A solution which resists change in its pH value on addition of acid/alkali is called the __________ solution.
Neutral
Ideal
Buffer
Zero pH
Otto cycle used in spark ignition petrol engines is also known as the constant __________ cycle.
Volume
Pressure
Heat
None of these
The most commonly used moderator in nuclear power plants is
Graphite
Light water
Heavy water
Beryllium
Age hardening is connected with
Babbitt metal
Gun metal
Stainless steel
Duralumin
__________ is used for tying the steel columns to concrete foundation.
Grouting
Eyebolt
Anchor bolts
Refractory castables
An alloy of Fe - 0.4 % C is
Cast iron
Hypo-eutectoid steel
Hyper-eutectoid steel
Eutectoid steel
Melting point & boiling points of liquid oxygen are respectively - 218.8°C & - 183°C, while the same for liquid nitrogen is - 210°C & - 195.8°C respectively. The difference in melting points of liquid oxygen & liquid nitrogen is not equal to 8.8
°C
°F
°K
°R
The thermodynamic law, 
= constant, is not followed by the
Free expansion of an ideal gas
Adiabatic expansion of steam in turbine
Adiabatic compression of air
Ideal compression of air
The pressure drop per unit length for laminar flow of fluid through a long pipe is proportional to (where, A = cross-sectional area of the pipe & D = Diameter of the pipe)
A
D
1/A
1/A2
The difference in one unit of Rockwell hardness number corresponds to a difference in the depth of indentation of __________ mm.
0.001
0.01
0.002
0.02