The efficiency of Joule cycle is
Greater than Carnot cycle
Less than Carnot cycle
Equal to Carnot cycle
None of these
Correct Answer :
B. Less than Carnot cycle
Related Questions
When shear force at a point is zero, then bending moment is _________ at that point.
Zero
Minimum
Maximum
Infinity
Young's modulus is defined as the ratio of
Volumetric stress and volumetric strain
Lateral stress and lateral strain
Longitudinal stress and longitudinal strain
Shear stress to shear strain
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.
The efficiency of a gas turbine is given by
(Net work output)/(Workdone by the turbine)
(Net work output)/(Heat supplied)
(Actual temperature drop)/(Isentropic temperature drop)
(Isentropic increase in temperature)/(Actual increase in temperature)
Hooke's law holds good up to
Yield point
Limit of proportionality
Breaking point
Elastic limit
Otto cycle consists of following four processes
Two isothermals 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 efficiency of Diesel cycle increases with
Decrease in cut-off
Increase in cut-off
Constant cut-off
None of these
One kg of carbon produces __________ kg of carbon dioxide.
3/7
7/3
11/3
3/11
The heat supplied to the gas at constant volume is (where m = Mass of gas, cv = Specific heat at constant volume, cp = Specific heat at constant pressure, T2 - T1 = Rise in temperature, and R = Gas constant)
mR (T2 - T1)
mcv (T2 - T1)
mcp (T2 - T1)
mcp (T2 + T1)
When a closely-coiled helical spring of mean diameter (D) is subjected to an axial load (W), the stiffness of the spring is given by
Cd⁴/D3n
Cd⁴/2D3n
Cd⁴/4D3n
Cd⁴/8D3n
The state of a substance whose evaporation from its liquid state is complete, is known as
Vapour
Perfect gas
Air
Steam
If a material expands freely due to heating it will develop
Thermal stresses
Tensile stress
Bending
No stress
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
A column that fails due to direct stress, is called
Short column
Long column
Weak column
Medium column
The ratio of specific heat at constant pressure (cp) and specific heat at constant volume (cv) is always __________ one.
Equal to
Less than
Greater than
None of these
All perfect gases change in volume by 1/273th of its original volume at 0°C for every 1°C change in temperature, when the pressure remains constant. This statement is called
Boyle's law
Charles' law
Gay-Lussac law
Joule's law
A double strap butt joint with equal straps is
Always in single shear
Always in double shear
Either in single shear or double shear
None of these
A cube subjected to three mutually perpendicular stress of equal intensity p expenses a volumetric strain
3p/E × (2/m - 1)
3p/E × (2 - m)
3p/E × (1 - 2/m)
E/3p × (2/m - 1)
The value of cp/cv for air is
1
1.4
1.45
2.3
A process, in which the working substance neither receives nor gives out heat to its surroundings during its expansion or compression, is called
Isothermal process
Hyperbolic process
Adiabatic process
Polytropic process
Which of the following is the correct statement of the second law of thermodynamics?
It is impossible to construct an engine working on a cyclic process, whose sole purpose is to convert heat energy into work.
It is impossible to transfer heat from a body at a lower temperature to a higher temperature, without the aid of an external source.
There is a definite amount of mechanical energy, which can be obtained from a given quantity of heat energy.
All of the above
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
When a system changes its state from one equilibrium state to another equilibrium state, then the path of successive states through which the system has passed, is known as
Thermodynamic law
Thermodynamic process
Thermodynamic cycle
None of these
Kelvin-Planck's law deals with
Conservation of work
Conservation of heat
Conversion of heat into work
Conversion of work into heat
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
The efficiency of Joule cycle is
Greater than Carnot cycle
Less than Carnot cycle
Equal to Carnot cycle
None of these
A process of heating crude oil to a high temperature under a very high pressure to increase the yield of lighter distillates, is known as
Cracking
Carbonisation
Fractional distillation
Full distillation
The general law for the expansion or compression of gases, is
pv = C
pv = m R T
pvn = C
pvγ = C
Modular ratio of two materials is the ratio of
Strains
Stress and strain
Shear stress and shear strain
Moduli and elasticity
The stress developed in a material at breaking point in extension is called
Breaking stress
Fracture stress
Yield point stress
Ultimate tensile stress