Hooke's law holds good up to
Yield point
Limit of proportionality
Breaking point
Elastic limit
Correct Answer :
B. Limit of proportionality
Related Questions
The stress induced in a body due to suddenly applied load compared to when it is applied gradually is
Same
Half
Two times
Four times
Steam coal is a
Pulverised coal
Brown coal
Coking bituminous coal
Non-coking bituminous coal
The work ratio of a gas turbine plant 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 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 hyperbolic process is governed by
Boyle's law
Charles' law
Gay-Lussac law
Avogadro's law
For the same compression ratio, the efficiency of Diesel cycle is __________ Otto cycle.
Greater than
Less than
Equal to
None of these
Which of the following has the minimum atomic mass?
Oxygen
Sulphur
Nitrogen
Carbon
The extremeties of any diameter on Mohr's circle represent
Principal stresses
Normal stresses on planes at 45°
Shear stresses on planes at 45°
Normal and shear stresses on a plane
The cycle in which heat is supplied at constant volume and rejected at constant pressure is known as
Dual combustion cycle
Diesel cycle
Atkinson cycle
Rankine cycle
The general law for the expansion or compression of gases, is
pv = C
pv = m R T
pvn = C
pvγ = C
The deformation of a bar under its own weight is _________ the deformation, if the same body is subjected to a direct load equal to weight of the body.
Equal to
Half
Double
Quadruple
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
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
The efficiency of the dual combustion cycle for the same compression ratio is __________ Diesel cycle.
Greater than
Less than
Equal to
None of these
The expansion ratio (r) is the ratio of (where v1 = Volume at the beginning of expansion, and v2 = Volume at the end of expansion)
v1/v2
v2/v1
(v1 + v2)/v1
(v1 + v2)/v2
When gas is heated at constant pressure, the heat supplied is utilised in
Increasing the internal energy of gas
Doing some external work
Increasing the internal energy of gas and also for doing some external work
None of the above
Elasticity of Mild Steel specimen is defined by
Hookes law
Yield point
Plastic flow
Proof stress
A cylindrical section having no joint is known as
Joint less section
Homogeneous section
Perfect section
Seamless section
When it is indicated that a member is elastic, it means that when force is applied, it will
Not deform
Be safest
Stretch
Not stretch
The measurement of a thermodynamic property known as temperature is based on
Zeroth law of thermodynamics
First law of thermodynamics
Second law of thermodynamics
None of these
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
The thermal efficiency of an ideal gas turbine plant is given by (where r = Pressure ratio)
rγ - 1
1 - rγ - 1
1 - (1/r) γ/γ - 1
1 - (1/r) γ - 1/ γ
The condition for the reversibility of a cycle is
The pressure and temperature of the working substance must not differ, appreciably, from those of the surroundings at any stage in the process
All the processes, taking place in the cycle of operation, must be extremely slow
The working parts of the engine must be friction free
All of the above
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
Diesel cycle consists of following four processes
Two isothermal and two isentropic
Two isentropic and two constant volumes
Two isentropic, one constant volume and one constant pressure
Two isentropic and two constant pressures
If the radius of wire stretched by a load is doubled, then its Youngs modulus will be
Doubled
Halved
Becomes four times
None of the above
Which of the following is the correct statement?
All the reversible engines have the same efficiency.
All the reversible and irreversible engines have the same efficiency.
Irreversible engines have maximum efficiency.
All engines are designed as reversible in order to obtain maximum efficiency.
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
For a beam, as shown in the below figure, the deflection at C is (where E = Young's modulus for the beam material, and I = Moment of inertia of the beam section.
Wl3/48 EI
Wa²b²/3EIl
[Wa/(a√3) x EIl] x (l² - a²)3/2
5Wl3/384 EI
In a belt drive, the pulley diameter is doubled, the belt tension and pulley width remaining same. The changes required in key will be
Increase key length
Increase key depth
Increase key width
Double all the dimensions