The total elongation produced in a bar of uniform section hanging vertically downwards due to its own weight is equal to that produced by a weight
Of same magnitude as that of bar and applied at the lower end
Half the weight of bar applied at lower end
Half of the square of weight of bar applied at lower end
One fourth of weight of bar applied at lower end
Correct Answer :
B. Half the weight of bar applied at lower end
Related Questions
The efficiency of the Carnot cycle may be increased by
Increasing the highest temperature
Decreasing the highest temperature
Increasing the lowest temperature
Keeping the lowest temperature constant
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.
Otto 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
The bending equation is
M/I = σ/y = E/R
T/J = τ/R = Cθ/l
M/R = T/J = Cθ/l
T/l= τ/J = R/Cθ
For which material the Poisson's ratio is more than unity
Steel
Copper
Aluminium
None of the above
The distillation carried out in such a way that the liquid with the lowest boiling point is first evaporated and recondensed, then the liquid with the next higher boiling point is then evaporated and recondensed, and so on until all the available liquid fuels are separately recovered in the sequence of their boiling points. Such a process is called
Cracking
Carbonisation
Fractional distillation
Full distillation
The behaviour of super-heated vapour is similar to that of
Perfect gas
Air
Steam
Ordinary gas
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
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 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
An open cycle gas turbine works on
Carnot cycle
Otto cycle
Joule's cycle
Stirling cycle
The section modulus of a circular section about an axis through its C.G., is
πd²/4
πd²/16
πd3/16
πd3/32
The entropy __________ in an irreversible cyclic process.
Remains constant
Decreases
Increases
None of these
The smallest quantity of a substance, which can exist by itself in a chemically recognizable form is known as
Element
Compound
Atom
Molecule
During which of the following process does heat rejection takes place in Carnot cycle?
Isothermal expansion
Isentropic expansion
Isothermal compression
Isentropic compression
The columns whose slenderness ratio is less than 80, are known as
Short columns
Long columns
Weak columns
Medium columns
The shear force at the centre of a simply supported beam with a gradually varying load from zero at both ends to w per metre at the centre, is
Zero
wl/4
wl/2
wl²/2
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
The property of a material which allows it to be drawn into a smaller section is called
Plasticity
Ductility
Elasticity
Malleability
Which of the following gas has the highest calorific value?
Coal gas
Producer gas
Mond gas
Blast furnace gas
Two shafts 'A' and 'B' transmit the same power. The speed of shaft 'A' is 250 r.p.m. and that of shaft 'B' is 300 r.p.m.
The shaft 'B' has the greater diameter
The shaft 'A' has the greater diameter
Both are of same diameter
None of these
First law of thermodynamics deals with
Conservation of heat
Conservation of momentum
Conservation of mass
Conservation of energy
The atomic mass of sulphur is
12
14
16
32
When a system changes its state from one equilibrium state to another equilibrium state, then the path of successive states through which the system has passed, is known as
Thermodynamic law
Thermodynamic process
Thermodynamic cycle
None of these
Hooke's law holds good up to
Yield point
Limit of proportionality
Breaking point
Elastic limit
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 equal to (where l = Original length, and δl = Change in length)
l/δl
δl/l
l.δl
l + δl
The shape of cantilever for uniformly distributed load will be
Straight line
Parabolic
Elliptical
Cubic
Which of the following has the highest calorific value?
Peat
Lignite
Bituminous coal
Anthracite coal
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