During which of the following process does heat rejection takes place in Carnot cycle?
Isothermal expansion
Isentropic expansion
Isothermal compression
Isentropic compression
Correct Answer :
C. Isothermal compression
Related Questions
Stirling cycle consists of
Two constant volume and two isentropic processes
Two constant volume and two isothermal processes
Two constant pressure and two isothermal processes
One constant volume, one constant pressure and two isentropic processes
The compression ratio for petrol engines is
3 to 6
5 to 8
15 to 20
20 to 30
A continuous beam is one which is
Fixed at both ends
Fixed at one end and free at the other end
Supported on more than two supports
Extending beyond the supports
When a closely-coiled helical spring of mean diameter (D) is subjected to an axial load (W), the deflection of the spring (δ) is given by (where d = Diameter of spring wire, n = No. of turns of the spring, and C = Modulus of rigidity for the spring material)
WD3n/Cd⁴
2WD3n/Cd⁴
4WD3n/Cd⁴
8WD3n/Cd⁴
The isothermal and adiabatic processes are regarded as
Reversible process
Irreversible process
Reversible or irreversible process
None of these
The pull required to tear off the plate per pitch length is (where p = Pitch of rivets, t = Thickness of plates, and σt, τ and σc = Permissible tensile, shearing and crushing stresses respectively)
(p - 2d) t × σc
(p - d) t × τ
(p - d) t × σt
(2p - d) t × σt
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 compression ratio for petrol engines is
3 to 6
5 to 8
10 to 20
15 to 30
The property of a working substance which increases or decreases as the heat is supplied or removed in a reversible manner, is known as
Enthalpy
Internal energy
Entropy
External energy
Which of the following statement is wrong?
The closed cycle gas turbine plants are external combustion plants.
In the closed cycle gas turbine, the pressure range depends upon the atmospheric pressure.
The advantage of efficient internal combustion is eliminated as the closed cycle has an external surface.
In open cycle gas turbine, atmosphere acts as a sink and no coolant is required.
The ultimate tensile stress of mild steel compared to ultimate compressive stress is
Same
More
Less
Unpredictable
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 thermodynamic difference between a Rankine cycle working with saturated steam and the Carnot cycle is that
Carnot cycle can't work with saturated steam
Heat is supplied to water at temperature below the maximum temperature of the cycle
A Rankine cycle receives heat at two places
Rankine cycle is hypothetical
Kerosene is distilled at
65° to 220°C
220° to 345°C
345° to 470°C
470° to 550°C
The ratio of maximum shear stress developed in a rectangular beam and a circular beam of the same cross-sectional area is
2/3
3/4
1
9/8
In an extensive property of a thermodynamic system
Extensive heat is transferred
Extensive work is done
Extensive energy is utilised
None of these
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
One kg of carbon produces __________ kg of carbon dioxide.
3/7
7/3
11/3
3/11
The value of cp/cv for air is
1
1.4
1.45
2.3
When a body is subjected to three mutually perpendicular stresses, of equal intensity, the ratio of direct stress to the corresponding volumetric strain is known as
Young's modulus
Modulus of rigidity
Bulk modulus
Poisson's ratio
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
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
The property of a material by virtue of which a body returns to its original, shape after removal of the load is called
Plasticity
Elasticity
Ductility
Malleability
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 ideal efficiency of a Brayton cycle without regeneration, with increase in pressure ratio will
Increase
Decrease
Remain unchanged
Increase/decrease depending on application
The moment of resistance of a balanced reinforced concrete beam is based on the stresses in
Steel only
Concrete only
Steel and concrete both
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
A fletched beam is used to
Change the shape of the beam
Effect the saving in material
Equalise the strength in tension and compression
Increase the cross-section of the beam
The relation between Young's modulus (E), shear modulus (C) and bulk modulus (K) is given by
E = 3K.C/(3K + C)
E = 6K.C/(3K + C)
E = 9K.C/(3K + C)
E = 12K.C/(3K + C)
The section modulus of a circular section about an axis through its C.G., is
πd²/4
πd²/16
πd3/16
πd3/32