For the same compression ratio, the efficiency of Diesel cycle is __________ Otto cycle.
Greater than
Less than
Equal to
None of these
Correct Answer :
B. Less than
Related Questions
The value of one bar (in S. I. units) is equal to
1 × 102 N/m2
1 × 103 N/m2
1 × 104 N/m2
1 × 105 N/m2
Otto cycle is also known as
Constant pressure cycle
Constant volume cycle
Constant temperature cycle
Constant temperature and pressure cycle
The ultimate tensile stress of mild steel compared to ultimate compressive stress is
Same
More
Less
Unpredictable
The efficiency of the Carnot cycle is (where T1 and T2 = Highest and lowest temperature during the cycle)
(T1/T2) - 1
1 - (T1/T2)
1 - (T2/T1)
1 + (T2/T1)
Stirling and Ericsson cycles are
Reversible cycles
Irreversible cycles
Semi-reversible cycles
Quasi-static cycles
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 total energy of a molecule is shared equally by the various degrees of freedom possessed by it. This law is known as
Law of equipartition of energy
Law of conservation of energy
Law of degradation of energy
None of these
The heat and work are mutually convertible. This statement is called __________ law of thermodynamics.
Zeroth
First
Second
Third
Slenderness of a column is zero when
Ends are firmly fixed
Column is supported on all sides throughout the length
Length is equal to radius of gyration
Length is twice the radius of gyration
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
Hooke's law holds good up to
Yield point
Limit of proportionality
Breaking point
Elastic limit
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
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
After reaching the yielding stage while testing a mild steel specimen, strain
Becomes constant
Starts decreasing
Increases without any increase in load
None of the above
The compression ratio for petrol engines is
3 to 6
5 to 8
10 to 20
15 to 30
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
When a bar is subjected to a change of temperature and its deformation is prevented, the stress induced in the bar is
Tensile stress
Compressive stress
Shear stress
Thermal stress
Reversed joule cycle is called
Carnot cycle
Rankine cycle
Brayton cycle
Bell Coleman cycle
The amount of heat required to raise the temperature of the unit mass of gas through one degree at constant volume, is called
Specific heat at constant volume
Specific heat at constant pressure
Kilo Joule
None of these
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
An open system is one in which
Heat and work crosses the boundary of the system, but the mass of the working substance does not crosses the boundary of the system
Mass of the working substance crosses the boundary of the system but the heat and work does not crosses the boundary of the system
Both the heat and work as well as mass of the working substance crosses the boundary of the system
Neither the heat and work nor the mass of the working substance crosses the boundary of the system
One kg of carbon produces __________ kg of carbon dioxide.
3/7
7/3
11/3
3/11
The gas constant (R) is equal to the
Sum of two specific heats
Difference of two specific heats
Product of two specific heats
Ratio of two specific heats
The energy stored in a body when strained within elastic limit is known as
Resilience
Proof resilience
Strain energy
Impact energy
A composite shaft consisting of two stepped portions having spring constants K₁ and K₂ is held between two rigid supports at the ends. Its equivalent spring constant is
K₁ K₂
(K₁ + K₂)/ 2
(K₁ + K₂)/ K₁ K₂
K₁ K₂/ (K₁ + K₂)
The isothermal and adiabatic processes are regarded as
Reversible process
Irreversible process
Reversible or irreversible process
None of these
The value of modulus of elasticity for mild steel is of the order of
2.1 × 10⁵ kg/cm²
2.1 × 10⁶ kg/cm²
2.1 × 10⁷ kg/cm²
0.1 × 10⁶ kg/cm²
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 __________ states that change of internal energy of a perfect gas is directly proportional to the change of temperature.
Boyle's law
Charle's law
Gay-Lussac law
Joule's law
The total elongation produced in a bar of uniform section hanging vertically downwards due to its own weight is equal to that produced by a weight
Of same magnitude as that of bar and applied at the lower end
Half the weight of bar applied at lower end
Half of the square of weight of bar applied at lower end
One fourth of weight of bar applied at lower end