Volumetric strain for a rectangular specimen of length l, breadth b and thickness t subjected to a pull of P is given by
e (1 - 2m)
e (1 - 2/m)
e (m - 2)
e (2/m - 1)
Correct Answer :
B. e (1 - 2/m)
Related Questions
The value of 1 mm of Hg is equal to
1.333 N/m2
13.33 N/m2
133.3 N/m2
1333 N/m2
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 bar of copper and steel form a composite system, which is heated to a temperature of 40°C. The stress induced in the copper bar will be
Tensile
Compressive
Shear
Zero
A column that fails due to direct stress, is called
Short column
Long column
Weak column
Medium column
The ratio of specific heat at constant pressure (cp) and specific heat at constant volume (cv) is always __________ one.
Equal to
Less than
Greater than
None of these
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
The lower layer of the beam as shown in the below figure, will be
In tension
In compression
Neither in tension nor in compression
None of these
Which of the following statement is incorrect?
The liquid fuels have higher calorific value than solid fuels
The solid fuels have higher calorific value than liquid fuels
A good fuel should have low ignition point
The liquid fuels consist of hydrocarbons
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
The processes occuring in open system which permit the transfer of mass to and from the system, are known as
Flow processes
Non-flow processes
Adiabatic processes
None of these
The value of Poisson's ratio for steel is between
0.01 to 0.1
0.23 to 0.27
0.25 to 0.33
0.4 to 0.6
According to Kelvin-Planck's statement, a perpetual motion of the __________ is impossible.
First kind
Second kind
Third kind
None of these
The compression ratio for petrol engines is
3 to 6
5 to 8
15 to 20
20 to 30
A cycle consisting of two adiabatic and two constant pressure processes is known as
Otto cycle
Ericsson cycle
Joule cycle
Stirling cycle
Kerosene is distilled at
65° to 220°C
220° to 345°C
345° to 470°C
470° to 550°C
The efficiency of Joule cycle is
Greater than Carnot cycle
Less than Carnot cycle
Equal to Carnot cycle
None of these
Efficiency of a riveted joint is the ratio of its strength (max. load it can resist without failure) to the strength of the un-punched plate in
Tension
Compression
Bearing
Any one of the above
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
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
Strain is equal to (where l = Original length, and δl = Change in length)
l/δl
δl/l
l.δl
l + δl
During a tensile test on a specimen of 1 cm cross-section, maximum load observed was 8 tonnes and area of cross-section at neck was 0.5 cm². Ultimate tensile strength of specimen is
4 tonnes/ cm²
8 tonnes/ cm²
16 tonnes/ cm²
22 tonnes/ cm²
The buckling load for a given material depends on
Slenderness ratio and area of cross-section
Poisson's ratio and modulus of elasticity
Slenderness ratio and modulus of elasticity
Slenderness ratio, area of cross-section and modulus of elasticity
For a beam, as shown in the below figure, when the load W is applied in the centre of the beam, the maximum deflection is
Wl3 / 48EI
5Wl3 / 384EI
Wl3 / 392EI
Wl3 / 384EI
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
A molecule consisting of one atom is known as
Mono-atomic
Di-atomic
Tri-atomic
Poly-atomic
The atomic mass of sulphur is
12
14
16
32
When coal is strongly heated continuously for 42 to 48 hours in the absence of air in a closed vessel, the process is known as __________ of fuel.
Atomisation
Carbonisation
Combustion
None of these
One kg of ethylene (C2H4) requires 2 kg of oxygen and produces 22/7 kg of carbon dioxide and __________ kg of water or steam.
9/7
11/7
7/4
1/4
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
When the expansion or compression takes place according to the law pvn = C, the process is known as
Isothermal process
Adiabatic process
Hyperbolic process
Polytropic process