The stress at which extension of the material takes place more quickly as compared to the increase in load is called
Elastic point of the material
Plastic point of the material
Breaking point of the material
Yielding point of the material
Correct Answer :
D. Yielding point of the material
Related Questions
The amount of heat required to raise the temperature of 1 kg of water through one Kelvin is called
Specific heat at constant volume
Specific heat at constant pressure
kilo-Joule
None of these
The weakest section of a diamond riveting is the section which passes through
The first row
The second row
The central row
One rivet hole of the end row
When the gas is heated at constant pressure, the heat supplied
Increases the internal energy of the gas
Increases the temperature of the gas
Does some external work during expansion
Both (B) and (C)
The unit of energy is S. I. units is
Joule (J)
Joule metre (Jm)
Watt (W)
Joule/metre (J/m)
Select the wrong statement
A Joule cycle consists of two constant volume and two isentropic processes.
An Otto cycle consists of two constant volume and two isentropic processes.
An Ericsson cycle consists of two constant pressure and two isothermal processes.
All of the above
The compression ratio for petrol engines is
3 to 6
5 to 8
10 to 20
15 to 30
The change of entropy, when heat is absorbed by the gas, is
Positive
Negative
Positive or negative
None of these
According to Kelvin-Planck's statement of 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 possible to construct an engine working on a cyclic process, whose sole purpose is to convert heat energy into work
It is impossible to construct a device which operates in a cyclic process and produces no effect other than the transfer of heat from a cold body to a hot body
None of the above
Which of the following statement is correct?
The increase in entropy is obtained from a given quantity of heat at a low temperature.
The change in entropy may be regarded as a measure of the rate of the availability or unavailability of heat for transformation into work.
The entropy represents the maximum amount of work obtainable per degree drop in temperature.
All of the above
When a body is subjected to two equal and opposite pushes, as a result of which the body tends to reduce its length, then
The stress and strain induced is compressive
The stress and strain induced is tensile
Both A and B is correct
None of these
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
A composite bar made up of steel and copper bars of equal lengths are heated through 100°C. The stresses developed shall be
Tensile in both the material
Tensile in steel and compressive in copper
Compressive in steel and tensile in copper
Compressive in both the materials
If the value of n = 0 in the equation pvn = C, then the process is called
Constant volume process
Adiabatic process
Constant pressure process
Isothermal process
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 heat and work are mutually convertible. This statement is called __________ law of thermodynamics.
Zeroth
First
Second
Third
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
The efficiency of Ericsson cycle is __________ Carnot cycle.
Greater than
Less than
Equal to
None of these
When a perfect gas is expanded through an aperture of minute dimensions, the process is known as
Isothermal process
Adiabatic process
Free expansion process
Throttling process
According to kinetic theory of gases, the velocity of molecules __________ with the increase in temperature.
Remains constant
Increases
Decreases
None of these
The ratio of specific heat at constant pressure (cp) and specific heat at constant volume (cv) is
Equal to one
Less than one
Greater than one
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 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
The bending stress in a beam is _________ section modulus.
Inversely proportional to two times
Directly proportional to
Inversely proportional to
None of these
In order to know whether a column is long or short, we must know its
Ultimate shear stress of the column
Factor of safety
Torque resisting capacity
Slenderness ratio
The maximum stress produced in a bar of tapering section is at
Smaller end
Larger end
Middle
Anywhere
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 efficiency of Diesel cycle increases with
Decrease in cut-off
Increase in cut-off
Constant cut-off
None of these
The absolute zero temperature is taken as
-273°C
73°C
237°C
-237°C
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
Formula based on IS codes is based on
Straight line formula
Eulers formula
Rankines formula
Secant formula