A closely-coiled helical spring is cut into two halves. The stiffness of the resulting spring will be
Same
Double
Half
One-fourth
Correct Answer :
B. Double
Related Questions
The strain energy stored in a body due to suddenly applied load compared to when it is applied gradually is
Same
Twice
Four times
Eight times
The area under the temperature-entropy curve (T - s curve) of any thermodynamic process represents
Heat absorbed
Heat rejected
Either (A) or (B)
None of these
The reading of the pressure gauge fitted on a vessel is 25 bar. The atmospheric pressure is 1.03 bar and the value of 'g' is 9.81 m/s2. The absolute pressure in the vessel is
23.97 bar
25 bar
26.03 bar
34.81 bar
When two plates are butt together and riveted with cover plates with two rows of rivets, the joint is known as
Lap joint
Butt joint
Single riveted single cover butt joint
Double riveted double cover butt joint
When a body is subjected to a direct tensile stress (σx) in one plane accompanied by a simple shear stress (τxy), the minimum normal stress is
(σx/2) + (1/2) × √(σx² + 4 τ²xy)
(σx/2) - (1/2) × √(σx² + 4 τ²xy)
(σx/2) + (1/2) × √(σx² - 4 τ²xy)
(1/2) × √(σx² + 4 τ²xy)
According to Avogadro's law, the density of any two gases is __________ their molecular masses, if the gases are at the same temperature and pressure.
Equal to
Directly proportional to
Inversely proportional to
None of these
Brayton cycle consists' of following four processes
Two isothermals and two isentropic
Two isentropic and two constant volumes
Two isentropic, one constant volume and one constant pressure
Two isentropic and two constant pressures
In compression test, the fracture in cast iron specimen would occur along
The axis of load
An oblique plane
At right angles to the axis of specimen
Would not occur
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
Workdone in a free expansion process is
Zero
Minimum
Maximum
Positive
The gas turbine cycle with regenerator improves
Thermal efficiency
Work ratio
Avoids pollution
None of these
The thickness of a thin cylindrical shell with hemispherical ends is __________ that of spherical ends.
Equal to
More than
Less than
None of these
Carnot cycle has maximum efficiency for
Petrol engine
Diesel engine
Reversible engine
Irreversible engine
Stirling and Ericsson cycles are
Reversible cycles
Irreversible cycles
Semi-reversible cycles
Quasi-static cycles
Modulus of rigidity may be defined as the ratio of
Linear stress to lateral strain
Lateral strain to linear strain
Linear stress to linear strain
Shear stress to shear strain
When a body is subjected to three mutually perpendicular stresses, of equal intensity, the ratio of direct stress to the corresponding volumetric strain is known as
Young's modulus
Modulus of rigidity
Bulk modulus
Poisson's ratio
The ratio of direct stress to volumetric strain in case of a body subjected to three mutually perpendicular stresses of equal intensity, is equal to
Young's modulus
Bulk modulus
Modulus of rigidity
Modulus of elasticity
The efficiency of Diesel cycle with decrease in cut-off
Increases
Decreases
First increases and then decreases
First decreases and then increases
The following cycle is used for air craft refrigeration
Brayton cycle
Joule cycle
Carnot cycle
Reversed Brayton cycle
According to Euler's column theory, the crippling load for a column of length (l) with one end fixed and the other end free is __________ the crippling load for a similar column hinged at both the ends.
Equal to
Less than
More than
None of these
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
A process, in which the temperature of the working substance remains constant during its expansion or compression, is called
Isothermal process
Hyperbolic process
Adiabatic process
Polytropic process
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 ideal efficiency of a Brayton cycle without regeneration, with increase in pressure ratio will
Increase
Decrease
Remain unchanged
Increase/decrease depending on application
Two closely coiled helical springs 'A' and 'B' are equal in all respects but the number of turns of spring 'A' is half that of spring 'B' The ratio of deflections in spring 'A' to spring 'B' is
1/8
1/4
1/2
2
In case of an under-reinforced beam, the depth of actual neutral axis is __________ that of the critical neutral axis.
Same as
Less than
Greater than
None of these
A cylindrical section having no joint is known as
Joint less section
Homogeneous section
Perfect section
Seamless section
The mass of excess air supplied is equal to
(23/100) × Mass of excess carbon
(23/100) × Mass of excess oxygen
(100/23) × Mass of excess carbon
(100/23) × Mass of excess oxygen
The efficiency of a Carnot engine depends on
Working substance
Design of engine
Size of engine
Temperatures of source and sink
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