The fuel mostly used in steam boilers is
Brown coal
Peat
Coking bituminous coal
Non-coking bituminous coal
Correct Answer :
D. Non-coking bituminous coal
Related Questions
Shear stress induced in a shaft subjected to tension will be
Maximum at periphery and zero at center
Maximum at center
Uniform throughout
None of the above
Which is the incorrect statement about Carnot cycle?
It is used as the alternate standard of comparison of all heat engines.
All the heat engines are based on Carnot cycle.
It provides concept of maximising work output between the two temperature limits.
All of the above
The efficiency and work ratio of a simple gas turbine cycle are
Very low
Low
High
Very high
If the rivets in adjacent rows are staggered and the outermost row has only one rivets, the arrangement of the rivets is called
Chain riveting
Zigzag riveting
Diamond riveting
Crisscross riveting
The stress necessary to initiate yielding is
Considerably greater than that necessary to continue it
Considerably lesser than that necessary to continue it
Greater than that necessary to stop it
Lesser than that necessary to stop it
A thin cylindrical shell of diameter (D) and thickness (t) is subjected to an internal pressure (p). The ratio of longitudinal strain to volumetric strain is
(m - 1)/ (2m - 1)
(2m - 1)/ (m - 1)
(m - 2)/ (3m - 4)
(m - 2)/ (5m - 4)
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
Producer gas is obtained by
Partial combustion of coal, coke, anthracite coal or charcoal in a mixed air steam blast
Carbonisation of bituminous coal
Passing steam over incandescent coke
Passing air and a large amount of steam over waste coal at about 650°C
The efficiency of Stirling cycle is __________ Carnot cycle.
Greater than
Less than
Equal to
None of these
The absolute zero pressure will be
When molecular momentum of the system becomes zero
At sea level
At the temperature of - 273 K
At the centre of the earth
Stirling and Ericsson cycles are
Reversible cycles
Irreversible cycles
Semi-reversible cycles
Quasi-static cycles
The maximum tangential stress in a thick cylindrical shell is always _________ the internal pressure acting on the shell.
Equal to
Less than
Greater than
None of these
First law of thermodynamics deals with
Conservation of heat
Conservation of momentum
Conservation of mass
Conservation of energy
Two shafts 'A' and 'B' transmit the same power. The speed of shaft 'A' is 250 r.p.m. and that of shaft 'B' is 300 r.p.m.
The shaft 'B' has the greater diameter
The shaft 'A' has the greater diameter
Both are of same diameter
None of these
The __________ is obtained when carbonisation of coal is carried out at 500° to 700° C.
Soft coal
Hard coal
Pulverised coal
Bituminous coal
A close cycle gas turbine gives __________ efficiency as compared to an open cycle gas turbine.
Same
Lower
Higher
None of these
A process, in which the temperature of the working substance remains constant during its expansion or compression, is called
Isothermal process
Hyperbolic process
Adiabatic process
Polytropic process
When both ends of a column are fixed, the effective length is
Its own length
Twice its length
Half its length
1/√2 × its length
The assumption made in Euler's column theory is that
The failure of column occurs due to buckling alone
The length of column is very large as compared to its cross-sectional dimensions
The column material obeys Hooke's law
All of the above
The general law of expansion or compression is pvn = C, The process is said to be hyperbolic, if n is equal to
0
1
γ
∝
The energy absorbed in a body, when it is strained within the elastic limits, is known as
Strain energy
Resilience
Proof resilience
Modulus of resilience
Within elastic limit, stress is
Inversely proportional to strain
Directly proportional to strain
Square root of strain
Equal to strain
The entropy of water at 0°C is assumed to be
1
0
-1
10
A bar of copper and steel form a composite system, which is heated to a temperature of 40°C. The stress induced in the copper bar will be
Tensile
Compressive
Shear
Zero
The general law for the expansion or compression of gases, is
pv = C
pv = m R T
pvn = C
pvγ = C
The efficiency of Diesel cycle with decrease in cut-off
Increases
Decreases
First increases and then decreases
First decreases and then increases
The hard coke is obtained when carbonisation of coal is carried out at
300° to 500°C
500° to 700°C
700° to 900°C
900° to 1100°C
The property of a material by virtue of which it can be beaten or rolled into plates is called
Malleability
Ductility
Plasticity
Elasticity
One kg of carbon monoxide requires 4/7 kg of oxygen and produces
11/3 kg of carbon dioxide gas
7/3 kg of carbon monoxide gas
11/7 kg of carbon dioxide gas
8/3 kg of carbon monoxide gas
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