The value of specific heat at constant pressure (cp) is __________ that of at constant volume (cv).
Less than
Equal to
More than
None of these
Correct Answer :
C. More than
Related Questions
True stress strain-curve for materials is plotted between
Load/original cross-sectional area and change in length/original length
Load/ instantaneous cross-sectional area and loge (original area/ instantaneous area)
Load/ instantaneous cross-sectional area and change in length/ original length
Load/ instantaneous area and instantaneous area/original area
Second law of thermodynamics defines
Heat
Work
Internal energy
Entropy
The efficiency of Joule cycle is
Greater than Carnot cycle
Less than Carnot cycle
Equal to Carnot cycle
None of these
The unit of energy is S. I. units is
Joule (J)
Joule metre (Jm)
Watt (W)
Joule/metre (J/m)
A body is subjected to a tensile stress of 1200 MPa on one plane and another tensile stress of 600 MPa on a plane at right angles to the former. It is also subjected to a shear stress of 400 MPa on the same planes. The maximum normal stress will be
400 MPa
500 MPa
900 MPa
1400 MPa
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.
A column is said to be a short column, when
Its length is very small
Its cross-sectional area is small
The ratio of its length to the least radius of gyration is less than 80
The ratio of its length to the least radius of gyration is more than 80
The absolute zero temperature is taken as
-273°C
73°C
237°C
-237°C
A cycle consisting of one constant pressure, one constant volume and two isentropic processes is known as
Carnot cycle
Stirling cycle
Otto cycle
Diesel cycle
If both Stirling and Carnot cycles operate within the same temperature limits, then efficiency of Stirling cycle as compared to Carnot cycle
More
Less
Equal
Depends on other factors
A body is subjected to a direct tensile stress of 300 MPa in one plane accompanied by a simple shear stress of 200 MPa. The maximum shear stress will be
-100 MPa
250 MPa
300 MPa
400 MPa
In the tensile test, the phenomenon of slow extension of the material, i. e. stress increasing with the time at a constant load is called
Creeping
Yielding
Breaking
Plasticity
The work ratio of simple gas turbine cycle depends upon
Maximum cycle temperature
Minimum cycle temperature
Pressure ratio
All of these
The process is adiabatic, if the value of n in the equation pvn = C, is
0
1
γ
∝
The efficiency of the Carnot cycle may be increased by
Increasing the highest temperature
Decreasing the highest temperature
Increasing the lowest temperature
Keeping the lowest temperature constant
Which of the following is an intensive property of a thermodynamic system?
Volume
Temperature
Mass
Energy
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)
The ratio of root mean square velocity to average velocity of gas molecules at a particular temperature is
0.086
1.086
1.086
4.086
A steel bar of 5 mm is heated from 25°C to 45°C and it is free to expand. The bar will induce
No stress
Shear stress
Tensile stress
Compressive stress
The radius of the Mohrs circle in the given figure is equal to
Sum of two principal stresses
Difference of two principal stresses
Half the sum of two principal stresses
Half the difference of two principal stresses
Strain is defined as the ratio of
Change in volume to original volume
Change in length to original length
Change in cross-sectional area to original cross-sectional area
Any one of the above
Mond gas is obtained by
Partial combustion of coal, coke, anthracite coal or charcoal in a mixed air steam blast
Carbonisation of bituminous coal
Passing steam over incandescent coke
Passing air and a large amount of steam over waste coal at about 650°C
In an isothermal process,
There is no change in temperature
There is no change in enthalpy
There is no change in internal energy
All of these
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 molecular mass expressed in gram (i.e. 1 g - mole) of all gases, at N. T. P., occupies a volume of
0.224 litres
2.24 litres
22.4 litres
224 litres
The ratio of the largest load in a test to the original cross-sectional area of the test piece is called
Elastic limit
Yield stress
Ultimate stress
Breaking stress
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
A mixture of gas expands from 0.03 m3 to 0.06 m3 at a constant pressure of 1 MPa and absorbs 84 kJ of heat during the process. The change in internal energy of the mixture is
30 kJ
54 kJ
84 kJ
114 kJ
The efficiency of Carnot cycle is maximum for
Gas engine
Petrol engine
Steam engine
Reversible engine
The columns whose slenderness ratio is less than 80, are known as
Short columns
Long columns
Weak columns
Medium columns