The solution of the differential equation $${{dy} \over {dx}} + {y^2} = 0$$ is

A reel of mass $$'‘m'’$$ and radius of gyration $$'‘'k’$$ is rolling down smoothly from rest with one end of the thread wound on it held in the ceiling as depicted in the figure. Consider the thickness of the thread and its mass negligible in comparison with radius $$‘'r'’$$ of the hub and the reel mass $$‘'m'’$$, Symbol $$'‘g’'$$ represents the acceleration due to gravity.

The tension in thread is

A reel of mass $$'‘m'’$$ and radius of gyration $$'‘'k’$$ is rolling down smoothly from rest with one end of the thread wound on it held in the ceiling as depicted in the figure. Consider the thickness of the thread and its mass negligible in comparison with radius $$‘'r'’$$ of the hub and the reel mass $$‘'m'’$$, Symbol $$'‘g’'$$ represents the acceleration due to gravity.

The linear acceletation of the reel is:

A bullet of mass ‘m’ travels at a very high velocity v (as shown in the figure) and gets embedded inside the block of mass ‘M’ initially at rest on a rough horizontal floor. The block with the bullet is seen to move a distance ‘s’ along the floor. Assuming $$\mu $$ to be the coefficient to kinetic friction between the block and the floor and ‘g’ the acceleration due to gravity what is the velocity v of the bullet?

A truss consists of horizontal members (AC, CD, DB and EF) and vertical members (CE and DE) having length 1 each. The members AE, DE and BF are inclined at $${45^0}$$ to the horizontal. For the uniformly distributed load ‘p’ per unit length on the member EF of the truss shown in figure given below, the force in the member CD is

A cylindrical body of cross - sectional area A, height $$H$$ and density $${\rho _s},$$ is immersed to a depth $$h$$ in a liquid of density $$\rho ,$$ and tied to the bottom with a string. The tension in the string is

A water container is kept on a weighing balance. Water from a tap is falling vertically into the container with a volume flow rate of $$'Q'$$; the velocity of the water when it hits the water surface is $$'U'$$. At a particular instant of time the total mass of the container and water is $$'m'.$$ The force registered by the weighing balance at this instant of time is

Air flows through a venture and into atmosphere. Air density is $$\rho $$; atmospheric pressure is $$'\,{P_a}';$$ throat diameter is exit diameter is $$'{D_t}';$$ and exit velocity is $$U.$$ the throat is connected to a cylinder containing a frictionless piston attached to a spring. The spring constant is $$'k'.$$ the bottom surface of the piston is exposed to atmosphere. Due to the flow, the piston moves by distance $$x.$$ assuming incompressible frictionless flow, $$x$$ is

A syringe with a frictionless plunger contains water and has at its end a $$100$$ $$mm$$ long needle of $$1$$ $$mm$$ diameter. The internal diameter of the syringe is $$10$$ $$mm.$$ Water density is $$1000\,\,kg/{m^3}.$$ . The plunger is pushed in at $$10$$ $$mm/s$$ and the water comes out as a jet.

Neglect losses in the cylinder and assume fully developed laminar viscous flow throughout the needle; the Darcy friction factor is $${64/R_e}$$. Where $${R_e}$$ is the Reynolds number. Given that the viscosity of water is $$1.0 \times {10^{ - 3}}\,\,kg/m\,\,\,s,$$ the force $$F$$ in newtons required on the plunger is

A syringe with a frictionless plunger contains water and has at its end a $$100$$ $$mm$$ long needle of $$1$$ $$mm$$ diameter. The internal diameter of the syringe is $$10$$ $$mm.$$ Water density is $$1000\,\,kg/{m^3}.$$ . The plunger is pushed in at $$10$$ $$mm/s$$ and the water comes out as a jet.

Assuming ideal flow, the force $$F$$ in Newton’s required on the plunger to push out the water is

In a counter flow heat exchanger, for the hot fluid the heat capacity $$= 2kJ/kg$$ $$K,$$ mass flow rate $$= 5 kg/s,$$ inlet temperature $$ = {150^ \circ }C$$, outlet temperature $$ = {100^ \circ }C$$. For the cold fluid, heat capacity $$= 4 kJ/kg$$ $$K,$$ mass flow rate $$= 10 kg/s,$$ inlet temperature=$$ = {20^ \circ }C$$. Neglecting heat transfer to the surroundings, the outlet temperature of the cold fluid in $$ = {^ \circ }C$$ is

A plate having $$10\,\,c{m^2}$$ area each side is hanging in the middle of a room of $$100\,\,{m^2}$$ total surface area. The plate temperature and emissivity are respectively $$800$$ $$K$$ and $$0.6.$$

The temperature and emissivity values for the surfaces of the room are $$300$$ $$K$$ and $$0.3$$ respectively. Boltzmannn constant $$\sigma = 5.67 \times {10^{ - 8}}\,\,W/{m^2}{K^4}.$$ The total heat loss from the two surfaces of the plate is

Consider a laminar boundary layer over a heated flat plate. The free stream velocity is $${U_\infty }.$$ At some distance $$x$$ from the leading edge the velocity boundary layer thickness is $${\delta _v}$$ and the thermal boundary layer is $${\delta _r}.$$ If the Prandtl number is greater than $$1,$$ then

Heat is being transferred by convection from water at $${48^ \circ }C$$ to a glass plate whose surface that is exposed to the water is at $${40^0}C.$$ The thermal conductivity of water is $$0.6$$ $$W/mK$$ and the thermal conductivity of glass is $$1.2$$ $$W/mK.$$ The spatial gradient of temp in the water at the water glass interface is
$$dT/dy = 1 \times {10^4}\,\,K/m.$$

The heat transfer coefficient $$h$$ in $$W/{m^2}K$$ is

Heat is being transferred by convection from water at $${48^ \circ }C$$ to a glass plate whose surface that is exposed to the water is at $${40^0}C.$$ The thermal conductivity of water is $$0.6$$ $$W/mK$$ and the thermal conductivity of glass is $$1.2$$ $$W/mK.$$ The spatial gradient of temp in the water at the water glass interface is
$$dT/dy = 1 \times {10^4}\,\,K/m...$$

The value of the temperature gradient in the glass at the water-glass interface in $$K/m$$ is

A manufacturer produces two types of products, $$1$$ and $$2,$$ at production levels of $${x_1}$$ and $${x_2}$$ respectively. The profit is given is$$2{x_1} + 5{x_2}.$$ The production constraints are $$$\eqalign{ & {x_1} + 3{x_2} \le 40 \cr & 3{x_1} + {x_2} \le 24 \cr & {x_1} + {x_2} \le 10 \cr & {x_1} > 0,\,{x_2} > 0 \cr} $$$

The maximum profit which can meet the constraints is

The sale of cycles in a shop in four consecutive months are given as $$70, 68, 82 95.$$ Exponentially smoothing average method with a smoothing factor of $$0.4$$ is used in forecasting. The expected number of sales in the next month is

A project consists of activities $$A$$ to $$M$$ shown in the net in the following figure with the duration of the activities marked in days.

The project can be completed

Market demand for springs is $$8,00,000$$ per annum. A company purchases these springs in lots and sells them. The cost of making a purchase order is Rs.$$1,200.$$ The cost of storage of springs is Rs.$$120$$ per stored piece per annum. The economic order quantity is

In terms of theoretical stress concentration factor $$\left( {{k_t}} \right)$$ and fatigue stress concentration factor $$\left( {{k_f}} \right),$$ the notch sensitivity $$'q'$$ is expressed as

The $$S$$-$$N$$ curve for steel becomes asymptotic nearly at

In a band brake the ratio of tight side band tension to the tension on the slack side is $$3.$$ If the angle of overlap of band on the drum is $${180^ \circ }$$ the coefficient of friction required between drum and the band is

In Oxyacetylene gas welding, temperature at the inner cone of the flame is around

A brass billet is to be excluded from its initial diameter of $$100mm$$ to a final diameter of $$50mm$$. The working temperature is $${700^ \circ }C$$ and the extrusion constant is $$250$$ $$MPa.$$ The force required for extrusion is

Cold working of steel is defined as working

With a solidification factor of $$0.97 \times {10^6}s/{m^2},$$ the solidification time (in seconds) for a spherical casting of $$200$$ $$mm$$ diameter is

Hardness of green sand mould increase with

Match the following

A shell of $$100$$ $$mm$$ diameter and $$100$$ $$mm$$ height with the corner radius of $$0.4$$ $$mm$$ is to be produced by cup drawing. The required blank diameter is

A threaded nut of $$M16, $$ $$ISO$$ metric type having $$2$$ $$mm$$ pitch with a pitch diameter of $$14.701$$ $$mm$$ is to be checked for its pitch diameter using two or three numbers of balls or rollers of the following sizes

A part shown in the gig is machined to the sizes given below

With $$100\% $$ confidence, the resultant dimension $$W$$ will have the specification

The dimensional limits on a shaft of $$25h7$$ are

A metal disc of $$20$$ $$mm$$ diameter is to be punched from a sheet of $$2$$ $$mm$$ thickness. The punch and the die clearance is $$3\% $$. The required punch diameter is

Quality screw threads are produced by

A good cutting fluid should have

A cylinder is turned on a lathe with orthogonal machining principle. Spindle rotates at $$200rpm$$. The axial feed rate is $$0.25$$ $$mm$$ per revolution. Depth of cut is $$0.4mm.$$ The rake angle is $${10^ \circ }.$$ In the analysis it is found that the shear angle is $${27.75^ \circ },$$

In the above problem, the coefficient of friction at the chip tool interface obtained using Earnest and Merchant theory is

A cylinder is turned on a lathe with orthogonal machining principle. Spindle rotates at $$200rpm$$. The axial feed rate is $$0.25$$ $$mm$$ per revolution. Depth of cut is $$0.4mm.$$ The rake angle is $${10^ \circ }.$$ In the analysis it is found that the shear angle is $${27.75^ \circ },$$

The thickness of the produced chip is

A batch of $$10$$ cutting tools could produce $$500$$ components while working at $$50$$ $$rpm$$ with a tool feed of $$0.25$$ $$mm/rev$$ and depth of cut of $$1$$ $$mm.$$ A similar batch of $$10$$ tools of the same specification could produce $$122$$ components while working at $$80$$ $$rpm$$ with a feed of $$0.25$$ $$mm/rev$$ and $$1$$ $$mm$$ depth of cut. How many components can be produced with one cutting tool at $$60$$ $$rpm$$?

Formation on build-up edge during machining can be avoided by using

The arc - voltage characteristics of a $$DC$$ power source has a linear power source characteristic of $$V=20+40L,$$ where $$V$$ is the arc voltage in volts and $$L$$ is the arc length in $$cm.$$ The static volt-ampere characteristic of the power source is approximated by a straight line with open circuit voltage $$=80V$$ and short circuit current is $$600Amps,$$ determine the optimum arc length for maximum power

The state of stress at a point P in a two dimensional loading is such that the Mohr's circle is a point located at 175 MPa on the positive normal stress axis.

The maximum and minimum principal stresses respectively from the Mohr's circle are

A simply supported laterally loaded beam was found to deflect more than a specified value. Which of the following measures will reduce the deflection?

Maximum shear stress developed on the surface of a solid circular shaft under pure torsion is 240 MPa. If the shaft diameter is doubled then the maximum shear stress developed corresponding to the same torque will be

The beams, one having square cross section and another circular cross-section,are subjected to the same amount of bending moment. If the cross sectional area as well as the material of both the beams are the same then

The second moment of a circular area about the diameter is given by (D is the diameter)

The state of stress at a point P in a two dimensional loading is such that the Mohr's circle is a point located at 175 MPa on the positive normal stress axis.

The distance of maximum and minimum principal stresses at the point ''P'' from the Mohr's circle are

A shaft subjected to torsion experiences a pure shear stress $$\tau $$ on the surface. The maximum principal stress on the surface which is at $$45$$⁰ to the axis will have a value

A $$200 \times 100 \times 50$$ mm steel block is subjected to a hydrostatic pressure of $$15$$ MPa. The Young's modulus and Poisson's ratio of the material are 200 GPa and $$0.3$$ respectively. The change in the volume of the block in mm³ is

Two identical circular rods of same diameter and same length are subjected to same magnitude of axial tensile force. One of the rods is made out of mild steel having the modulus of elasticity of 206 GPa. The other rod is made out of cast iron having he modulus of elasticity of 100 GPa. Assume both the materials to be homogeneous and isotropic and the axial force causes the same amount of uniform stress in both the rods. The stresses developed are within the proportional limit of the respective materials. Which of the following observations is correct?

The circular disc shown in its plan view in the figure rotates in a plane parallel to the horizontal plane about the point $$O$$ at a uniform angular velocity $$\omega $$. Two other points $$A$$ and $$B$$ are located on the line $$OZ$$ at distances $${r_A}$$ and $${r_B}$$ from $$O$$ respectively.

The acceleration of point $$B$$ with respect to point $$A$$ is a vector of magnitude

The circular disc shown in its plan view in the figure rotates in a plane parallel to the horizontal plane about the point $$O$$ at a uniform angular velocity $$\omega $$. Two other points $$A$$ and $$B$$ are located on the line $$OZ$$ at distances $${r_A}$$ and $${r_B}$$ from $$O$$ respectively.

The velocity of point $$B$$ with respect to point $$A$$ is a vector of magnitude

The lengths of the links of a 4-bar linkage with revolute pairs only are $$p,q,r$$ and $$s$$ units. Given that $$p < q < r < s.$$ Which of these links should be the fixed one, for obtaining a ‘double crank’ mechanism?

The mechanism used in a shaping machine is

The overall gear ratio in a 2 stage speed reduction gear box (with all spur gears) is 12. The input and output shafts of the gear box are collinear. The countershafts which is parallel to the input and output shafts has a gear (Z₂ teeth) and pinion (Z₃ = 15 teeth) to mesh with pinion (Z₁ = 16 teeth) on the input shafts and gear (Z₄ teeth) on the output shafts respectively. It was decided to use a gear ratio of 4 with 3 module in the first stage and 4 module in the second stage.

Z₂ and Z₄ are

The overall gear ratio in a 2 stage speed reduction gear box (with all spur gears) is 12. The input and output shafts of the gear box are collinear. The countershafts which is parallel to the input and output shafts has a gear (Z₂ teeth) and pinion (Z₃ = 15 teeth) to mesh with pinion (Z₁ = 16 teeth) on the input shafts and gear (Z₄ teeth) on the output shafts respectively. It was decided to use a gear ratio of 4 with 3 module in the first stage and 4 module in the second stage.

The centre distance in the second stage is

For a certain engine having an average speed of $$1200$$ rpm, a flywheel approximated as a solid disc, is required for keeping the fluctuation of speed within $$2$$% about the average speed. The fluctuation of kinetic energy per cycle is found to be $$2$$kJ. What is the least possible mass of the flywheel if its diameter is not exceed $$1$$ m?

A flexible rotor-shaft system comprises of a $$10kg$$ rotor disc placed in the middle of a mass-less shaft of diameter $$30$$ $$mm$$ and length $$500mm$$ between bearings (shaft is being taken mass-less as the equivalent mass of the shaft is included in the rotor mass) mounted at the ends. The bearings are assumed to simulate simply supported boundary conditions. The shaft is made of steel for which the value of $$E$$ is $$\,2.1\, \times \,{10^{11}}\,$$. Pa. What is the critical speed of rotation of the shaft?

A uniform rigid slender bar of mass $$10$$ $$kg.$$ is hinged at the left end is suspended with the help of spring and damper arrangement as shown in the figure where $$K = 2kN/m,$$ $$C =500Ns/m$$ and the stiffness of the torsional spring $${K_\theta }$$ is 1 kN/m/rad. Ignore the hinge dimensions.

The un-damped natural frequency of oscillations of the bar about the hinge point is

A uniform rigid slender bar of mass $$10$$ $$kg.$$ is hinged at the left end is suspended with the help of spring and damper arrangement as shown in the figure where $$K = 2kN/m,$$ $$C =500Ns/m$$ and the stiffness of the torsional spring $${K_\theta }$$ is 1 kN/m/rad. Ignore the hinge dimensions.

The damping coefficient in the vibration equation is given by

Nitrogen gas (molecular weight $$28$$) is enclosed in a cylinder by a piston, at the initial condition of $$2$$ bar, $$298$$ $$K$$ and $$1\,\,{m^3}$$. In a particular process, the gas slowly expands under isothermal condition, until the volume becomes $$2{m^3}.$$ Heat exchange occurs with the atmosphere at $$298$$ $$K$$ during this process.

The entropy change for the system during the process in $$kJ/K$$ is

Match the following

In a Rankine cycle, regeneration results in higher efficiency because

Considering the variation of static pressure and absolute velocity in an impulse stream turbine, across one row of moving blades

Nitrogen gas (molecular weight $$28$$) is enclosed in a cylinder by a piston, at the initial condition of $$2$$ bar, $$298$$ $$K$$ and $$1\,\,{m^3}$$. In a particular process, the gas slowly expands under isothermal condition, until the volume becomes $$2{m^3}.$$ Heat exchange occurs with the atmosphere at $$298$$ $$K$$ during this process.

The work interaction for the Nitrogen gas is

Considering the relationship $$TdS=dU+PdV$$ between the entropy $$(S),$$ internal energy $$(U),$$ pressure $$(P),$$temperature $$(T)$$ and volume $$(V),$$
Which of the following statements is correct?

An industrial heat pump operates between the temperatures of $${27^ \circ }C$$ and $$ - {13^ \circ }C.$$ The rates of heat addition and heat rejection are $$750$$ $$W$$ and $$1000$$ $$W,$$ respectively. The $$COP$$ for the heat pump is

A $$2$$ $$kW,$$ $$40$$ liter water heater is switched on for $$20$$ minutes. The heat capacity $${C_p}$$ for water is $$4.2$$ $$kJ/kg$$ $$K.$$ Assuming all the electrical energy has gone into heating the water, increase of the water temperature in degree centigrade is