A beam is having-a-triangular cross section with its neutral axis XX. The section modulus about XX is given by
ISRO Scientist or Engineer Mechanical 2012
For the following questions answer them individually
A rectangular column is subjected to an eccentric load P at distance ‘e’ from centroidal Axis. The stress diagram at Cross- section will be
Two shafts A & B are made of same material. The radius of the shaft A is half that of shaft B. The power transmitted by the shaft A will be ___________ that of shaft B.
Four linear elastic springs are connected to mass ‘M’ as shown in Figure. The natural frequency of the system is
Which bearing offers lowest friction
A circular disk of radius R rolls without slipping at a velocity V. The magnitude of the velocity at point P shown in the figure is
In the viscous damped vibration, the logarithmic decrement value over five cycles is found to be 8.11. What is viscous damping factor of vibratory system?
An elevator weighing 1000Kg attains an upward velocity of 4m/sec in two seconds with uniform acceleration. The tension (in N) in supporting cable will be $$(g = 9.8m/sec^2)$
A block weighting 981 N is resting on Horizontal surface. The co-efficient of friction between the block and horizontal surface is $$\mu = 0.2.$$ A vertical cable attached to block provides partial support as shown. A man can pull horizontally with a force of 100 N. What will be the tension (T)(in N)in the cable if the man is just able to move the block to the right?
A vehicle suspension system consists of a leaf spring and a damper. The stiffness of the leaf spring is 3.6 KN/m and damping constant of the damper is 400 Ns/m. If the mass is 50Kg, then the damping factor and damped natural frequency respectively are
A rotating disc of 1m diameter has two eccentric masses of 0.5 kg each at radi of 50mm and 60mm at angularposition of $$0^\circ$$ and $$150^\circ$$, respectively. A balancing mass of 0.1Kg is to be used to balance the rotor. Whatis the radial position of balancing mass?
Two mating spur gears have 40 & 120 teeth respectively. The pinion rotates at 1200 rpm and transmit torque of 20Nm. The torque transmitted by the gear is
The figure below shows a steel rod of $$25 mm^2$$ cross sectional area. It is loaded at four points, Kk, L, M, N. Assume E steel = 200 GPa. The total change in length of the rod due to loading is
Planetary gear is in contact with the fixed gear as shown in the figure. The number of rotations made by the planetary gear for one rotation of the arm is
The Mohr circle reduces to a point when the body is subjected to
Shear stress distribution for a rectangular beam subjected to transverse loading is
Area moment of inertia for the quadrant shown below is
A column of length ‘L’is fixed at bottom end and hinged at the other end. This column is restrained from lateral displacement at $${\frac{1}{3}^{rd}} $$height. The buckling load is given by
A shaft has two heavy rotors mounted on it. The transverse natural frequency considering each rotor separately is 100 hz & 200 hz respectively. The lowest critical speed is
A mass ‘M' is suspended from a ceiling through a string of length ‘L’. This mass moves in a circle of horizontal radius ‘r’ at constant speed such that it is a conical pendulum. The tension in the string will be
The stress in the rod AB in the pin jointed truss ABCD is
The number of degrees of freedom for the following mechanism is
A plate is held by a chain AB through hinge joints. The plate is pulled with a force T as shown in figure. The tension in the chain is given by
In a turn buckle joint, both mating rods will have
In flat belt drive, the belt can be subjected to a maximum tension (T) and centrifugal tension $$(T_c)$$. The condition of transmission of maximum power is given by
The diameter of a soap bubble which has an inside pressure of $$2.5 N/m^2$$ over the atmospheric pressure and a surface tension of 0.0125 N/m is
Find the loss of head dueto friction in a smooth pipe of rectangular cross section of $$1m \times 0.5m$$ and 10m long. Velocity of flow is 10 m/s and the friction coefficient is 0.01962.
Whena supersonic flow is admitted into a convergent, the flow will
Which configuration measures the stagnation pressure?
The maximum lift in a centrifugal pump would be close to ‘X’ if the pump is handling cold water $$(25^\circ C)$$ from an open tank at sea level with no friction and turbulence loses, where ‘X’ is equal to
Both pressure and velocity of steam drops in the moving blades of
A model of a golf ball is to be studied to determine the effects of the dimples. A sphere 10 times larger in diameter than an actual golf ball is used in the wind tunnel study. What speed should be selected for the model to simulate a prototype speed of50 m/s?
The sound of explosion on a ship located 10km away from the beach was heard 28.6 seconds after the explosion was seen. Estimate the temperatureofair at that time.
A spherical balloon is filled with helium at sea level. Helium and balloon material together weigh 500 N.If the net upward lift force on the balloon is also 500 N, whatis the diameter of the balloon?
Air at $$ 20^\circ C $$ and $$ 10^5 $$ Pa enters the bottom of an $$ 85^\circ $$ conical flow meter duct at a mass flow rate of 0.3 kg/s, as shown in the figure. It supports the centered conical body by steady annular flow around the cone and exits at the same velocity as it enters. Estimate the weight of the body in Newtons
A jet of water issues from a nozzle with a velocity 20 m/s on a flat plate moving away from it at 10 m/s. The cross sectional area of the jet is $$ 0.01 m^2$$ and the density of water $$= 1000 kg/m^3.$$ The force developed on the plate is
The laminar boundary layer thickness varies as
An increase in pressure of a liquid from 7.5 MPa to 15 MPa results into 0.2 percent decrease in its volume. The Coefficient of compressibility of the liquid in $$ m^2/N $$ is
A reservoir of capacity $$0.01m^3$$ is completely filled with a fluid of coefficient of compressibility $$0.75 x 10^{-9} m^2/N$$. The amount of fluid that will spill over $$(in m^3)$$,if pressure in the reservoir is reduced by $$ 2 \times 10^7 N/m^2 $$ is
The extent of pressure produced due to water hammer depends on
Rank of the matrix
$$ A = \begin{bmatrix}1 & 1 & 2 \\1 & 2 & 3 \\ 0 & -1 & 1 \end{bmatrix} $$ is
The value of $$t$$ for which $$A + tB$$ is perpendicular to $$C$$ where $$A = i + 2j + 3k, B = -i + 2j + k$$ and $$C = 3i + j$$
$$ \overline{A} \times \overline{B} $$ is a vector
The equation of the plane through the line $$ \frac {x - 1}{3} = \frac {y - 4}{2} = \frac {z - 4}{-2} $$ and parallel to the line $$ \frac {x + 1}{2} = \frac {y - 1}{-4} = \frac {z + 2}{1} $$ is
Let $$E$$ and $$F$$ be any two events with $$4 P(E \cup F) = 0.8, P(E) = 0.4$$ and $$P (E/F) = 0.3$$.Then $$(F)$$ is .
The approximate value of y(0.1) from $$\frac {dy} {dx} = x^2 y-1, y(0) = 1$$ is
1+ i is equivalent to
In a class of 45 students, the mean mark of 25 girls is 32 and the mean mark of 20 boys is 27.5. What is the class mean?
If $$ L \left\{ f(t) \right\} = F (s),$$ then the value of $$ L \left\{ e^{-at} f(t) \right\} $$ is
The probability that A happens is $$\frac{1}{3}$$. The odds against happening of A are
Draft on pattern for casting is provided for
Welding spatter is
Which of the following statementsis false about annealing? Annealing is done to
The property of corrosion resistance of chromium Stainless Steel is due to
Hot working operation is carried out at
The engineering and true strains for a bar which is doubled in length during tension test are
The purpose of adding wood flour to the moulding sand is to improve
Stretch forming is a process in which
In which type of welding, a pool of molten metal is used?
A mild steel block of width 40mm is being milled using a straight slab cutter 70mm diameter with 30 teeth. If the cutter rotates at 40 rpm, and depth of cut is 2mm, what is the value of maximum uncut chip thickness when the table feed is 20 mm/min?
Match the list I with list II and select the correct answer from the codes given in the lists below:
A shaft has a dimension $$ \phi 35^{\frac {-0.009} {-0.025}},$$ the respective values of fundamental deviation and tolerance are
When a material sustains steady loads for long periods of time, the material may continue to deform until they may tend to fracture under the same load. This phenomenon is known as
Which one of the following is a wrong statement?
The most popular and standard typeforall purpose tool steels is 18:4:1 High Speed Steel (H.S.S.), which contains.
Water is boiled at $$1\times10^5 $$ Pa pressure in a coffee maker equipped with an immersion-type electric_heating-element. The coffee maker initially contains 1 kg of water. Once boiling started, it is observed that half of the water in the coffee maker evaporated in 18 minutes. If the heat loss from the coffee maker is negligible, the power rating of the heating element is
An adiabatic heat exchanger is used to heat cold water at $$15^\circ C$$ entering at a rate of 5 kg/s by hotair at $$90^\circ C$$ entering also at rate of 5 kg/s. If the exit temperatureof hot air is $$20^\circ C$$, the exit temperature of cold water is
Logmean area ‘A’ can be given as.
Nusselt number is the ratio of
Zeroth law of thermodynamics is not valid for the following
When air expands from initial pressure $$P_1$$ and volume $$V_1$$ tofinal volume $$5V_1$$ following the law $$PV^n = C$$
Air is compressed to half the volume at constant pressure, then the change in entropy
A cycle is shown below on P-V diagram
This cycle is represented in T-S diagram by
If 2 bar of air at $$27^\circ C$$ is heated to $$177^\circ C$$ at constant volume, the pressure will be
A friction less heat engine can be 100 percent efficient only if its exhaust temperature is
An ideal engine absorbs heat at $$ 127^\circ C$$ andrejects at $$ 77^\circ C$$. Theefficiency is
A Francis turbine running at 200 rpm develops a power of 5000 kW under a head of 25m.
The power output under a head of 100 m will be
Steam expands in a turbine from 40 bar, $$ 500^\circ C$$ to 0.10 bar isentropically. Assuming ideal conditions, given enthalpy drop 1198.8 kJ/kg, nozzle angle $$16^\cir$$ and N as 300 rpm. Mean diameter of the wheel,if the turbine were of simple impulse stage, will be
A refrigerator removes heat froma refrigerated space at $$0-5^\circ C$$ at a rate of 0.35 kJ/s and rejects it to an environment at $$20^\circ C$$. The minimum required power input is
For the same compression ratio, the thermodynamic cycles in the order of decreasing efficiencies are
