The most applicable failure theory for metals like Aluminium is
ISRO Scientist or Engineer Mechanical Dec 2017
For the following questions answer them individually
Which one of the following is FALSE?
A statistical process control chart which shows the number of defects found in a subgroup of fixed size is
Complex irregular three dimensional surfaces can be located using the following method
The force in member BC of steel truss structure shown in figure below is (Cross section of each member is A, Length of each member is ‘l')
Buckling loads (Pi) of 4 columns of equal length and cross section, but with different end conditions are shown below. Which ofthe following is TRUE?
The bar AB weighs 10 kg per meter and is supported by cable AC and a pin at B. Reaction at B is ( take g = 10 m/s$$^2$$)
Arrange the metals Aluminium, Copper, Iron & Silver in increasing order of thermal conductivity
Modulus of resilience for the below material is
Which of the following is FALSE?
Two dimensionally equal blocks made of material M1 and M2 are placed on flat horizontal surface as shown in figure below. Young’s modulus of the materials are El & E2 resp. A
uniform pressure ‘p’ is applied over the blocks through a thick plate (AB) symmetrically placed over the blocks. For E1 > E2, consider the statements below.
(p) Stress in both blocks are same
(q) Strain in both blocks are same
(r) Plate AB tilts and point B moves downward
(s) Plate AB tilts and point A moves downward
Which of the above sentencesare correct?
In tolerancing of a part, unless otherwise specified, individual features of size must
A horizontal bar AB assumedto be rigid, is supported by two wires CE & DF, having lengths L and 2L respectively and pinned at A. If each wire hascross sectional area A, the tensile stress $$\sigma_1$$ and $$\sigma_2$$ in wires CE and DF are respectively,
A 3 m long steel shaft has to transmit 7.5 kW at 3600 rpm. Required shaft diameter is given by (Take allowable shear stress = 100 N/mm$$^2$$, $$\pi^2 = 10$$)?
For thin cylindrical shell structures loaded in compression, the design is based on
Thefrictional shear stress ($$\tau$$) in metal forming is expressed as
where ‘m’is the friction shear factor and ‘$$\overline{\sigma}$$’ is the flow stress
Governing differential equation for small deflections of elastic beamsis given by
A point moves accordingto the relation $$x = 8t^2 \cos(\omega t), y = -4t^3 \sin(\omega t)$$, where x and y are in meters, and t in seconds. If angular velocity $$\omega = 8 \pi$$ rad/sec, velocity vector of the point at t = 0.5 sec is given by
A 10 mm thick plate-1 is welded to another plate-2 (10 mm thk) using fillet weld of thickness 10 mm,on two sides of plate-1 as shown in figure. Plate-1 projects outside plate-2 by 85 mm. An end load of 1 KN acts on plate-1. The primary shear stress produced in the weld throat is
Isochoric changesin ideal gas are characterized by
A cantilever beam ofcross section area ‘A’, moment of Inertia ‘I’ and length ‘L’ is having
natural frequency $$\omega 1$$. If the beam is accidently broken into two halves, the natural
frequency of the remaining cantilever beam $$\omega 2$$ will be such that
In CAD, the geometric transformation is expressed as P * = [T]P where T is the transformation matrix. If the matrix T is diagonal, then the transformation is called
A water tank is located 3 m above ground and depth of water in tank is 2 m. Exit pipe is 50 mm in dia and 50 m long. Velocity of water at the exit at the ground level is approximately (Take friction factor f = 0.05, g = 10 m/s$$^2$$)
The work ratio of a gas turbine is a function of
The distribution of temperature T, at a particular instant, across a large concrete wall, 1 m thick, which is heated from one sideis given by the equation $$T = 150 - 80x + 16x^2$$, where the distance x is in meters and Tis in degree Celsius. Thermal conductivity of wall is 0.6 W/mK, area of cross section is 10 m?. The heat accumulated in unit time at this instant in the concrete wall is —
Which one of the following is the permanent mould casting process?
Identify the geometric characteristic that describe the feature geometry and the inter-relationship of part features
Isothermal compressibility of an ideal gas is
Datum features on the part are
The eigen values of $$A = \begin{bmatrix}2 & 2 & 4 \\2 & -1 & 2 \\4 & 2 & 2 \end{bmatrix}$$ are,
In process charts, the symbol used for inspection is
Efficiency of gas turbines lies between
Which one of the following is impulse turbine?
Which of the following is FALSEfor bolted joints?
Root opening of a Single Vee groove weld joint of plate thickness "t" is
A cubic B-spline curve requires minimum .......... control points.
Transportation method is concerned with
The reaction in which a liquid phase transform into twodifferent solid phases is called
Margin wearin drill is due to
The specific speed of the Kaplan turbine is
If $$f(t) = e^{at}$$, its Laplace Transform (for s > a) is given by
Smallest thickness which can be measured bya slip gauge is
The deflection of an elastic member at the point of application of a force in the direction of that force is given by the derivative of member's total strain energy taken with respect to applied force. This is known as
Thumb rule between feed and nose radius in rough turning is
Which of the following is FALSE?
Which of the following is true for ductile materials?
The specific metal cutting energy is expressed as
where '$$\alpha$$' is rake angle, '$$\beta$$' is friction angle, '$$\phi$$' is shear angle and '$$\tau$$' shear stress
For isotropic materials, the modulus of Elasticity in tension and shear (E and G)are related to the Poisson’s ratio (v) as follows
Which of the following is NOT true?
A block (of cross section 4 $$\times$$ 3 m size) of 20 kg mass rests on a flat horizontal surface as shown in figure below. If the coefficient of friction between the block and the surface is $$\frac{1}{4}$$, the force ‘F’ which will cause block to move is approximately given by
A point P moves along the path $$y = x^2 - 4$$. What is the displacement when the point moves from x = 1 to x = 3
The pulley system shown in figure has a mass of 1.5 kg and a radius of gyration of 0.2 m. The angular acceleration of the pulleys, when the suspended masses are released is
A U tube manometer shown in figure is used to measure the gauge pressure of water of density $$\rho_1 = 1000 kg/m^3$$. If the density of manometer liquid $$\rho_2$$ is $$12000 kg/m^3$$ hl = 0.5 m & h2 = 1.0 m, gauge pressure at ‘A’, the centre of tube is (take g = 10 m/s$$^2$$)
A man draws 3 balls from a jug containing 5 whiteballs and 7 black balls. He gets Rs. 20 for each white ball and Rs. 10 for each black ball. What is his expectation?
The missing dimension in the following simple part is
Which one of the following is FALSE about Boronizing process?
In dynamic balancing of machines, which of the following is NOT a method of measuring the magnitude andlocation of correction weight for a two plane correction?
The stress produced in a wire of diameter 6 mm, when it is bend around a large cylinder of diameter 2 m can be obtained as (Young’s modulus of both wire and cylinder = 200 GPa, the stress strain curve of the material is given below)
The critical pressure ratio for maximum discharge in steam nozzle is
The type of locator used to prevent jamming during locating of a workpiece is
A carton carrying vessel of mass 10 tons (width = length = 5 m, height = 6 m), floats on water. The mass of contents of the vessel are symmetrically placed. If the vessel tilts by 0.01 radians by moving a 50 kg carton from the centre by a distance of 2 m towards side in horizontal direction, the metacentric height of the vessel is (g = 10m/s$$^2$$)
The maximum value of reduction in rolling process is
Where ‘D’ is roll diameter and ‘$$\alpha$$’ is the angleof bite
Which of the following is TRUE for vibration of a mechanical system
What is the maximum rate that a heat pump which uses 1 kW of electric power can supply heat to a house at $$27^\circ C$$ when the outside temperature is $$12^\circ C$$
Evaluate $$\int_{0}^{1} \int_{0}^{1} \frac{1}{\sqrt{(1 - x^2)(1 - y^2)}} dxdy$$
White iron structure consists of
A cantilever beam of rectangular cross section (depth ‘d’, width ‘b’ & length ‘L’) is subjected to a shear force ‘F’ at its free end as shown in figure. The beam is made of material which follows maximum shear stress theory. Which of the following is TRUE?
A jet engine consumes 1 kgof fuel for each 40 kg ofair intake. Fuel consumption is 1 kg/sec. When aircraft travels in still air at 200 m/sec, velocity of discharge gases with respect to engine is 700 m/sec. The power developed by engine is
Which of the following is most appropriate for vapour power cycles?
Load Vs Displacement curve shown in the following figure pertains to
The reheatfactor $$R_f$$ for a steam turbineis usually in the range of
Adaptive responserate forecasting is related to
Process in which lowest tolerances in cast products of ferrous and non ferrous metals can be achieved is
Pickling treatment is cleaning the casting with
Element which makes steel stainless
Isentropic process is related to
Tolerances generally followed for tooling design are
Whichof the following is FALSE about Normal distribution?
The temperature of the products of combustion when the maximum amountof chemical energy is converted to thermal energy is
Fredric W Taylor introduced a system of working known as
