When coal is strongly heated continuously for 42 to 48 hours in the absence of air in a closed vessel, the process is known as __________ of fuel.
Atomisation
Carbonisation
Combustion
None of these
Correct Answer :
B. Carbonisation
Related Questions
The stress developed in a material at breaking point in extension is called
Breaking stress
Fracture stress
Yield point stress
Ultimate tensile stress
The value of modulus of elasticity for mild steel is of the order of
2.1 × 10⁵ kg/cm²
2.1 × 10⁶ kg/cm²
2.1 × 10⁷ kg/cm²
0.1 × 10⁶ kg/cm²
The hyperbolic process is governed by
Boyle's law
Charles' law
Gay-Lussac law
Avogadro's law
If Kh is the torque resisting capacity of a hollow shaft and Ks is that of a solid shaft, of the same material, length and weight. Then,
Kh > Ks
Kh < Ks
Kh = Ks
None of these
A process, in which the gas is heated or expanded in such a way that the product of its pressure and volume remains constant, is called
Isothermal process
Hyperbolic process
Adiabatic process
Polytropic process
A body is subjected to a direct tensile stress of 300 MPa in one plane accompanied by a simple shear stress of 200 MPa. The maximum shear stress will be
-100 MPa
250 MPa
300 MPa
400 MPa
A circular shaft fixed at, A has diameter D for half of its length and diameter D/2 over the other half, as shown in the below figure. If the rotation of B relative to A is 0.1 radian, the rotation of C relative to B will be
0.4 radian
0.8 radian
1.6 radian
3.2 radian
Stirling and Ericsson cycles are
Reversible cycles
Irreversible cycles
Semi-reversible cycles
Adiabatic irreversible cycles
If both Stirling and Carnot cycles operate within the same temperature limits, then efficiency of Stirling cycle as compared to Carnot cycle
More
Less
Equal
Depends on other factors
Which of the following statement is wrong?
The deformation of the bar per unit length in the direction of the force is called linear strain.
The Poisson's ratio is the ratio of lateral strain to the linear strain.
The ratio of change in volume to the original volume is called volumetric strain.
The bulk modulus is the ratio of linear stress to the linear strain.
An adiabatic process is one in which
No heat enters or leaves the gas
The temperature of the gas changes
The change in internal energy is equal to the mechanical workdone
All of the above
The amount of heat required to raise the temperature of the unit mass of gas through one degree at constant volume, is called
Specific heat at constant volume
Specific heat at constant pressure
Kilo Joule
None of these
The pull required to crush the rivet per pitch length is
p.t.σt
d.t.σc
π/4 × d² × σt
π/4 × d² × σc
The bending stress in a beam is _________ section modulus.
Inversely proportional to two times
Directly proportional to
Inversely proportional to
None of these
In order to prevent crushing of masonry at the base of the dam, the maximum stress should be __________ the permissible stress of the soil.
Equal to
Less than
More than
None of these
The ratio of direct stress to volumetric strain in case of a body subjected to three mutually perpendicular stresses of equal intensity, is equal to
Young's modulus
Bulk modulus
Modulus of rigidity
Modulus of elasticity
The value of one bar (in S. I. units) is equal to
1 × 102 N/m2
1 × 103 N/m2
1 × 104 N/m2
1 × 105 N/m2
When gas is heated at constant pressure, the heat supplied is utilised in
Increasing the internal energy of gas
Doing some external work
Increasing the internal energy of gas and also for doing some external work
None of the above
When a body is subjected to a direct tensile stress (σ) in one plane, then maximum normal stress occurs at a section inclined at __________ to the normal of the section.
0°
30°
45°
90°
A material obeys hooks law up to
Plastic limit
Elastic limit
Yield point
Limit of proportionality
True stress strain-curve for materials is plotted between
Load/original cross-sectional area and change in length/original length
Load/ instantaneous cross-sectional area and loge (original area/ instantaneous area)
Load/ instantaneous cross-sectional area and change in length/ original length
Load/ instantaneous area and instantaneous area/original area
One reversible heat engine operates between 1600 K and T2 K and another reversible heat engine operates between T2 K and 400 K. If both the engines have the same heat input and output, then temperature T2 is equal to
800 K
1000 K
1200 K
1400 K
A composite bar made up of steel and copper bars of equal lengths are heated through 100°C. The stresses developed shall be
Tensile in both the material
Tensile in steel and compressive in copper
Compressive in steel and tensile in copper
Compressive in both the materials
A vertical column has two moments of inertia (i.e. Ixx and Iyy ). The column will tend to buckle in the direction of the
Axis of load
Perpendicular to the axis of load
Maximum moment of inertia
Minimum moment of inertia
The amount of heat required to raise the temperature of __________ water through one degree is called kilojoules.
1 g
10 g
100 g
1000 g
According to Regnault's law, the specific heat at constant pressure (cp) and specific heat at constant volume (cv) _________ with the change in pressure and temperature of the gas.
Change
Do not change
Both (A) and (B)
None of these
The capacity of a strained body for doing work on the removal of the straining force, is called
Strain energy
Resilience
Proof resilience
Impact energy
Which of the following cycles is not a reversible cycle?
Carnot
Ericsson
Stirling
None of the above
The standard value of atmospheric pressure taken at sea level is
1.013 bar
760 mm of Hg
1013 × 102 N/m2
All of these
Kerosene is distilled at
65° to 220°C
220° to 345°C
345° to 470°C
470° to 550°C