The ideal efficiency of a Brayton cycle with regeneration, with increase in pressure ratio will
Increase
Decrease
Remain unchanged
Increase/decrease depending on application
Correct Answer :
B. Decrease
Related Questions
Which of the following is an intensive property of a thermodynamic system?
Volume
Temperature
Mass
Energy
The compression ratio for petrol engines is
3 to 6
5 to 8
15 to 20
20 to 30
Strain energy is the
Energy stored in a body when strained within elastic limits
Energy stored in a body when strained up to the breaking of a specimen
Maximum strain energy which can be stored in a body
Proof resilience per unit volume of a material
Which of the following statement is correct?
The stress is the pressure per unit area
The strain is expressed in mm
Hook's law holds good upto the breaking point
Stress is directly proportional to strain within elastic limit
The reading of the pressure gauge fitted on a vessel is 25 bar. The atmospheric pressure is 1.03 bar and the value of 'g' is 9.81 m/s2. The absolute pressure in the vessel is
23.97 bar
25 bar
26.03 bar
34.81 bar
The pressure exerted by an ideal gas is ________ of the kinetic energy of all the molecules contained in a unit volume of gas.
One-half
One-third
Two-third
Three-fourth
A cantilever beam is one which is
Fixed at both ends
Fixed at one end and free at the other end
Supported at its ends
Supported on more than two supports
The isothermal and adiabatic processes are regarded as
Reversible process
Irreversible process
Reversible or irreversible process
None of these
Which is the false statement about true stress strain method?
It does not exist
It is more sensitive to changes in both metallurgical and mechanical conditions
It gives a more accurate picture of the ductility
It can be correlated with stress strain values in other tests like torsion, impact, combined stress tests etc.
In case of an under-reinforced beam, the depth of actual neutral axis is __________ that of the critical neutral axis.
Same as
Less than
Greater than
None of these
A cycle consisting of __________ and two isothermal processes is known as Stirling cycle.
Two constant pressure
Two constant volume
Two isentropic
One constant pressure, one constant volume
For which material the Poisson's ratio is more than unity
Steel
Copper
Aluminium
None of the above
The processes occuring in open system which permit the transfer of mass to and from the system, are known as
Flow processes
Non-flow processes
Adiabatic processes
None of these
The bending stress in a beam is _________ section modulus.
Inversely proportional to two times
Directly proportional to
Inversely proportional to
None of these
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
When a body is subjected to a direct tensile stress (σx) in one plane accompanied by a simple shear stress (τxy), the maximum shear stress is
(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)
The property of a material which allows it to be drawn into a smaller section is called
Plasticity
Ductility
Elasticity
Malleability
Workdone in a free expansion process is
Zero
Minimum
Maximum
Positive
In open cycle gas turbine plants
The indirect heat exchanger and cooler is avoided
Direct combustion system is used
A condenser is used
All of the above
A concentrated load is one which
Acts at a point on a beam
Spreads non-uniformly over the whole length of a beam
Spreads uniformly over the whole length of a beam
Varies uniformly over the whole length of a beam
The rivets are used for __________ fastenings.
Permanent
Temporary
Semi-permanent
None of these
The natural solid fuel is
Wood
Coke
Anthracite coal
Pulverised coal
The heat and mechanical energies are mutually convertible. This statement was established by
Boyle
Charles
Joule
None of these
A tri-atomic molecule consists of __________ atoms.
One
Two
Three
Four
A thin mild steel wire is loaded by adding loads in equal increments till it breaks. The extensions noted with increasing loads will behave as under
Uniform throughout
Increase uniformly
First increase and then decrease
Increase uniformly first and then increase rapidly
Relation between cp and cv is given by (where cp = Specific heat at constant pressure, cv = Specific heat at constant volume, γ = cp/cv, known as adiabatic index, and R = Gas constant)
cv/ cp =R
cp - cv = R
cv = R/ γ-1
Both (B) and (C)
The volumetric or molar specific heat at constant pressure is the product of
Molecular mass of the gas and the specific heat at constant volume
Atomic mass of the gas and the gas constant
Molecular mass of the gas and the gas constant
None of the above
According to First law of thermodynamics,
Total internal energy of a system during a process remains constant
Total energy of a system remains constant
Workdone by a system is equal to the heat transferred by the system
Internal energy, enthalpy and entropy during a process remain constant
The ratio of molar specific heats for mono-atomic gas is
1
1.4
1.67
1.87
The shear force diagram of a cantilever beam of length l and carrying a uniformly distributed load of w per unit length will be
A right angled triangle
An isosceles triangle
An equilateral triangle
A rectangle