The efficiency of Diesel cycle depends upon
Temperature limits
Pressure ratio
Compression ratio
Cut-off ratio and compression ratio
Correct Answer :
D. Cut-off ratio and compression ratio
Related Questions
The limit of eccentricity for no tensile conditions for a column of circular section of diameter (D) is
d/4
d/8
d/12
d/16
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
The neutral axis of a transverse section of a beam passes through the centre of gravity of the section and is
In the vertical plane
In the horizontal plane
In the same plane in which the beam bends
At right angle to the plane in which the beam bends
Which of the following has the minimum atomic mass?
Oxygen
Sulphur
Nitrogen
Carbon
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
A pressure vessel is said to be a thick shell, when
It is made of thick sheets
The internal pressure is very high
The ratio of wall thickness of the vessel to its diameter is less than 1/10.
The ratio of wall thickness of the vessel to its diameter is greater than 1/10.
The ratio of molar specific heats for mono-atomic gas is
1
1.4
1.67
1.87
The strain energy stored in a solid circular shaft subjected to shear stress (τ), is: (Where G = Modulus of rigidity for the shaft material)
τ²/ 2G × Volume of shaft
τ/ 2G × Volume of shaft
τ²/ 4G × Volume of shaft
τ/ 4G × Volume of shaft
The specific heat at constant volume is
The amount of heat required to raise the temperature of unit mass of gas through one degree, at constant pressure
The amount of heat required to raise the temperature of unit mass of gas through one degree, at constant volume
The amount of heat required to raise the temperature of 1 kg of water through one degree
Any one of the above
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
When a body is subjected to a direct tensile stress (σx) in one plane accompanied by a simple shear stress (τxy), the maximum normal stress i
(σx/2) + (1/2) × √(σx² + 4 τ²xy)
(σx/2) - (1/2) × √(σx² + 4 τ²xy)
(σx/2) + (1/2) × √(σx² - 4 τ²xy)
(1/2) × √(σx² + 4 τ²xy)
Which of the following is the extensive property of a thermodynamic system?
Pressure
Volume
Temperature
Density
When a perfect gas is expanded through an aperture of minute dimensions, the process is known as
Isothermal process
Adiabatic process
Free expansion process
Throttling process
Diesel cycle consists of following four processes
Two isothermal and two isentropic
Two isentropic and two constant volumes
Two isentropic, one constant volume and one constant pressure
Two isentropic and two constant pressures
The torsional rigidity of a shaft is expressed by the
Maximum torque it can transmit
Number of cycles it undergoes before failure
Elastic limit up to which it resists torsion, shear and bending stresses
Torque required to produce a twist of one radian per unit length of shaft
Which of the following gas has the highest calorific value?
Coal gas
Producer gas
Mond gas
Blast furnace gas
The extremeties of any diameter on Mohr's circle represent
Principal stresses
Normal stresses on planes at 45°
Shear stresses on planes at 45°
Normal and shear stresses on a plane
Which of the following is a proper sequence?
Proportional limit, elastic limit, yielding, failure
Elastic limit, proportional limit, yielding, failure
Yielding, proportional limit, elastic limit, failure
None of the above
One Joule (J) is equal to
1 N-m
1 kN-m
10 N-m/s
10 kN-m/s
The heat and work are mutually convertible. This statement is called __________ law of thermodynamics.
Zeroth
First
Second
Third
Stirling and Ericsson cycles are
Reversible cycles
Irreversible cycles
Semi-reversible cycles
Adiabatic irreversible cycles
The maximum stress produced in a bar of tapering section is at
Smaller end
Larger end
Middle
Anywhere
A beam which is fixed at one end and free at the other is called
Simply supported beam
Fixed beam
Overhanging beam
Cantilever beam
Which of the following is an irreversible cycle?
Carnot
Stirling
Ericsson
None of the above
The condition for the reversibility of a cycle is
The pressure and temperature of the working substance must not differ, appreciably, from those of the surroundings at any stage in the process
All the processes, taking place in the cycle of operation, must be extremely slow
The working parts of the engine must be friction free
All of the above
Proof resilience per material is known as
Resilience
Proof resilience
Modulus of resilience
Toughness
The strain energy stored in a body due to suddenly applied load compared to when it is applied gradually is
Same
Twice
Four times
Eight times
The stress induced in a body, when suddenly loaded, is ________ the stress induced when the same load is applied gradually.
Equal to
One-half
Twice
Four times
High air-fuel ratio in gas turbines
Increases power output
Improves thermal efficiency
Reduces exhaust temperature
Do not damage turbine blades
A coil is cut into two halves, the stiffness of cut coil will be
Double
Half
Same
None of these