Which of the following statement is correct?
The stress is the pressure per unit area
The strain is expressed in mm
Hook's law holds good upto the breaking point
Stress is directly proportional to strain within elastic limit
Correct Answer :
D. Stress is directly proportional to strain within elastic limit
Related Questions
A closely-coiled helical spring is cut into two halves. The stiffness of the resulting spring will be
Same
Double
Half
One-fourth
A tri-atomic molecule consists of __________ atoms.
One
Two
Three
Four
The general gas energy equation is (where Q1 - 2 = Heat supplied, dU = Change in internal energy, and W1 - 2 = Work done in heat units)
Q1 - 2 = dU + W1 - 2
Q1 - 2 = dU - W1 - 2
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Q1 - 2 = dU × W1 - 2
The compression ratio for petrol engines is
3 to 6
5 to 8
15 to 20
20 to 30
The heat and work are mutually convertible. This statement is called __________ law of thermodynamics.
Zeroth
First
Second
Third
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 value of specific heat at constant pressure (cp) is __________ that of at constant volume (cv).
Less than
Equal to
More than
None of these
The ratio of molar specific heats for mono-atomic gas is
1
1.4
1.67
1.87
The heating of gas at constant volume is governed by
Boyle's law
Charles' law
Gay-Lussac law
Avogadro's law
For same compression ratio and for same heat added
Otto cycle is more efficient than Diesel cycle
Diesel cycle is more efficient than Otto cycle
Efficiency depends on other factors
Both Otto and Diesel cycles are equally efficient
Tensile strength of a material is obtained by dividing the maximum load during the test by the
Area at the time of fracture
Original cross-sectional area
Average of (A) and (B)
Minimum area after fracture
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
The shape of cantilever for uniformly distributed load will be
Straight line
Parabolic
Elliptical
Cubic
The compression ratio for Diesel engines is
3 to 6
5 to 8
15 to 20
20 to 30
The rivets are used for __________ fastenings.
Permanent
Temporary
Semi-permanent
None of these
Percentage reduction in area performing tensile test on cast iron may be of the order of
50 %
25 %
20 %
30 %
The gas in cooling chamber of a closed cycle gas turbine is cooled at
Constant volume
Constant temperature
Constant pressure
None of these
Hooke's law holds good up to
Yield point
Limit of proportionality
Breaking point
Elastic limit
Strain energy is the
Energy stored in a body when strained within elastic limits
Energy stored in a body when strained up to the breaking of a specimen
Maximum strain energy which can be stored in a body
Proof resilience per unit volume of a material
Elasticity of Mild Steel specimen is defined by
Hookes law
Yield point
Plastic flow
Proof stress
The specific heat of water is
1.817
2512
4.187
None of these
Relation between cp and cv is given by (where cp = Specific heat at constant pressure, cv = Specific heat at constant volume, γ = cp/cv, known as adiabatic index, and R = Gas constant)
cv/ cp =R
cp - cv = R
cv = R/ γ-1
Both (B) and (C)
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
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
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Stirling cycle
Otto cycle
None of these
The general gas equation is (where p = Pressure, v = Volume, m = mass, T = Absolute temperature, and R = Gas constant)
pv = mRT
pv = RTm
pvm = C
pv = (RT)m
Which of the following is correct?
Absolute pressure = Gauge pressure + Atmospheric pressure
Gauge pressure = Absolute pressure + Atmospheric pressure
Atmospheric pressure = Absolute pressure + Gauge pressure
Absolute pressure = Gauge pressure - Atmospheric pressure
The absolute zero pressure will be
When molecular momentum of the system becomes zero
At sea level
At the temperature of - 273 K
At the centre of the earth
The entropy __________ in an irreversible cyclic process.
Remains constant
Decreases
Increases
None of these
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Same
Twice
Four times
Eight times