Consider the following motions :
1. Piston reciprocating inside an engine cylinder
2. Motion of a shaft between foot-step bearings
Which of the above can rightly be considered as successfully constrained motion?

A rotor weighing 2 kN is supported on bearings A and B which are 1 m apart. The centre of mass of the rotor is at a distance 0.4 m from bearing A. It is observed that there is an unbalanced couple of magnitude 300 N-m which leaves the shaft balanced statically.The dynamic reactions at the supports will be

A cam is a mechanical member used to impart a desired motion to a follower by direct contact. Which one of the under-listed follower motion types will produce the least jerk to the system?

In a circular are cam with a roller follower, acceleration of the follower depends on
1. cam speed and location of centre of circular arc
2. roller diameter and radius of circular arc
Which of the above is/are correct?

A manufacturing company is selling a product for 15 per unit with variable cost of  10 per unit. The fixed cost of the asset is 50,000. How many units should be produced to breakeven?

Hot wire anemometer is used to measure_______________?

A gear of 28 cm pitch circle diameter has 40 teeth. The circular pitch will nearly be

Consider the following statements regarding gear tooth designing for gear drive :
1. Tooth profiles not designed as per ‘law of gearing’ will cause vibration and impact problems even at low speed.
2. As the gears go through their mesh, the pitch point must remain stationary on the line of centres.
3. In a correctly designed tooth profile, the line of action of successive instantaneous points of contact will pass through the stationary pitch point.
Which of the above statements are correct?

The flywheel of a steam engine has a radius of gyration of 1 m and mass 2000 kg. The starting torque of the engine is 2000 N-m. The kinetic energy of the flywheel after 10 seconds from start is

Consider two shafts connected with two gears as per the following options :
1. One on each shaft.
2. Through an intermediate gear mounted on an intermediate shaft, and every shaft having one gear only.
3. Through an intermediate gear mounted on an intermediate shaft having two gears, whereas the other shafts have one gear each
Which of the above represent(s) a simple gear train?

A riveting machine is driven by a constant-torque 3 kW motor. The moving parts including the flywheel are equivalent to 150 kg at 0.6 m radius. One riveting operation takes 1 second and absorbs 10000 N-m of energy. The speed of the flywheel is 300 r.p.m. before riveting. What is the speed (to nearest 10 r.p.m.) after riveting and what is the number of rivets that can be closed per minute?

Which one of the following statements is correct?

The thickness of the continuous weld used for connecting a horizontal square bar of 150 mm size and of cantilevered length 500 mm to a vertical plate, with the bar carrying a 25 kN vertical load at its outer tip, given that the permissible direct shear stress of the weld is 20 N/mm², is

A shaft of 50 mm diameter transmits a torque of 800 N-m. The width of the rectangular key used is 10 mm. The allowable shear stress of the material of the key being 40 MPa, the required length of the key would be

A governor is said to be hunting if the speed of the engine

The diameter of the pin in a bushed pin type flexible coupling is to be increased for the purpose of

The problem of interference in involute profile gears can be overcome by which one of the following means?

The bearing modulus for a bearing is 1628. What is the bearing characteristic number considered for bearing design?

Two shafts of diameter 30 mm each are connected by a flange coupling. Six bolts, each of diameter 8 mm, are used on a pitch circle of diameter 90 mm. If the allowable shear stress of the bolt material is 80 MPa, what is the torque transmitting capacity of the bolts to the nearest 10 units?

While selecting the elements of power transmission with speed reduction, the order of preference based on a minimum cost is

A solid shaft is designed to transmit 100 kW while rotating at N r.p.m. If the diameter of the shaft is doubled and allowed to operate at 2 N r.p.m., the power that can be transmitted by the latter shaft is

What shall be the centre distance between the axes of pinion and gear when a 20° full-depth involute profile pinion with 20 teeth meshes with a gear that has 50 teeth for a module of 6 mm?

The diameter of a shaft to transmit 25 kW at 1500 r.p.m. given that the ultimate strength is 150 MPa and the factor of safety is 3, will nearly be

A thick lubrication is

If the dynamic load capacity of a ball bearing is increased to 1.5 times its earlier value without changing its equivalent load, the life of the bearing increases to

The speed of the crankshaft is found to vary between 120 r.p.m. and 150 r.p.m. during one cycle of operation. What is the coefficient of fluctuation of speed?

The state of stress at a point when completely specified enables one to determine the
1. maximum shearing stress at the point
2. stress components on any arbitrary plane containing that point
Which of the above is/are correct?

A body is subjected to a direct tensile stress of 300 MPa in one plane accompanied by a simple shear stress of 200 MPa. The maximum normal stress on the plane will be

A metal piece under the stress state of three principal stresses 30, 10 and 5 kg/mm² is undergoing plastic deformation. The principal strain rates will be in the proportions of

An isotropic elastic material is characterized by

The Miller indices of a material in a plane are proportional to

The modulus of elasticity of E-glass is 72 GPa and that of epoxy resin is 3 GPa. The modulus of elasticity (to the nearest unit magnitude) for a composite material consisting of 60% by volume of continuous E-glass fibre and 40% epoxy resin for the matrix, when stressed under isostress conditions, is

In developing abrasive ceramics which are used to wear, grind or cut away other materials which are (necessarily) softer, they should have, besides wear resistance,
1. a high degree of toughness
2. a low degree of toughness
3. refractoriness
Which of the above is/are correct?

Consider the following in case of high-energy forming processes :
1. The evacuation between die and blank in explosive forming is done by a vacuum pump.
2. The pressure waves produced in water in explosive forming deform the blank to the die shape.
3. The electrohydraulic forming makes use of discharge of large amount of electrical energy used in a capacitor blank.
4. In Petroforge, the piston is moved by combustion of fuel moving at the rate of 150-200 m/s.
Which of the above are correct?

In abrasive jet machining process, the main mechanism of material removal takes place due to

Consider that the following materials are usable for manufacturing dies, moulds in investment casting process for the purpose of large-scale production :
1. Aluminum alloy
2. Magnesium alloy
3. Brass
4. Low-carbon steel
Which of the above are correctly usable?

The occurrence of casting defect ‘rat tail’ is possible because of
1. soft ramming of sand
2. continuous large flat surface on the mould
3. excessive hardness of the mould
Which of the above reasons are correct?

Components produced by die casting have finer grain, higher strength and greater hardness at the skin than at the centre due to

A 125 mm long, 10 mm diameter stainless steel rod is being turned to 9 mm diameter, 0.5 mm depth of cut. The spindle rotates at 360 r.p.m. With the tool traversing at an axial speed of 175 mm/min, the metal removal rate is nearly

The feed in face milling for a width of 70 mm with a cutter of 160 mm diameter, having 10 inserts and rotating at 360 r.p.m., with a feed rate of 0.5 m/min, is nearly

A lathe consumes 500 W when running idle and 2500 W when cutting a steel specimen at 30 m/min. If the depth of cut is 4 mm and feed rate is 0.25 mm/rev, the cutting force and the approximate value of torque at a spindle run of 120 r.p.m. will respectively be

For a shaper, the length of stroke is 210 mm, the number of double strokes per minute is 32 and the ratio of return time to cutting time is  2 : 3. The cutting speed will be

The headstock of a lathe has 9 speeds with minimum speed of 100 r.p.m. and maximum speed of 1600 r.p.m. If the speeds are in geometric progression, then the ratio is

Surface cracking occurring at low temperatures in hydrostatic extrusion is known as

Flank wear occurs mainly on the
1. nose part of the cutting tool
2. front relief face and side relief face of the cutting tool
3. face of the cutting tool at the shortest distance from the cutting edge
Which of the above is/are correct?

A part programme for any arbitrary object is given as follows :
N001     G91      G71 M03           S600     EBOB
N002     G00      X 10.00             Y10.00 EOB
N003     G00      Z–10.00            EOB
N004     G83      Z–60.00            F100     EOB
N005     G80      EOB
N006     M02      EOB
The above programming format will be used as Canned cycle for

In case of TIG welding of aluminum alloys, the amount of shielding gas used can be determined from the band of white deposit (aluminum oxide) alongside of the weld bead. A hairline width white band indicates that the quantum of shielding gas used has been
1. more than required
2. lesser than required
3. adequate as required
Which of the above is correct?

A cylindrical Robot can reach any point in a cylinder of height L and radius 2L, except for the points in an inner cylinder of height L and radius L. The volume for the cylindrical Robot work envelope will be

Consider the following statements about forging:
1. Forgings have high strength and ductility.
2. Forgings offer great resistance to impact and fatigue loads.
3. Forging assures uniformity in density as well as dimensions of the forged parts.
Which of the above statements are correct?

Endurance limit is of primary concern in the design of a/an
1. rotating shaft
2. industrial structure
3. column
4. machine base
Which of the above is/are correct?

A spherical waterdrop of 1 mm in diameter splits up in air into 64 smaller drops of equal size. The surface tension coefficient of water in air is 0.073 N/m. The work required in splitting up the drop is

Consider the following statements pertaining to stability of floating bodies:
1. A floating body will be stable when the centre of gravity is above the centre of buoyancy.
2. The position of metacentres corresponding to different axes of rotation are generally different for the same floating object.
3. For cargo ships, the metacentric height varies with loading.
Which of the above statements are correct?

Water is coming out from a tap and falls vertically downwards. At the tap opening, the stream diameter is 20 mm with uniform velocity of 2 m/s. Assuming steady inviscid flow, constant pressure atmosphere everywhere, and neglecting curvature and surface tension effects, the diameter of the stream 0.5 m below the tap opening is nearly

Consider the following statements:
1. At low Reynolds numbers of any flow, viscous forces dominate over inertial forces.
2. Transition from laminar to turbulent flow occurs over a range of Reynolds numbers depending on the surface presented to the flow.
Which of the above statements is/are correct?

In a steady laminar flow of a given discharge through a circular pipe of diameter D, the head loss is proportional to

The centre-line velocity in a pipe flow is 2m/s. What is the average flow velocity in the pipe if the Reynolds number of the flow is 800?

During a constant pressure expansion of a gas, 33.3% heat is converted into work while the temperature rises by 20 K. The specific heat of the gas at constant pressure as a proportion of work, W is

A system of 100 kg mass undergoes a process in which its specific entropy increases from 0.3 kJ/kg K to 0.4 kJ/kg K. At the same time, the entropy of the surroundings decreases from 80 kJ/kg K to 75 kJ/kg K. The process is

A reversible heat engine rejects 80% of the heat supplied during a cycle of operation. If the engine is reversed and operates as a refrigerator, then its coefficient of performance shall be

For the same efficiency of the Brayton cycle and the Carnot cycle working between temperature limits of T_max and T_min, the power contribution of the Brayton cycle will be

A heat engine working on the Carnot cycle receives heat at the rate of 50 kW from a source at 1300 K and rejects it to a sink at 400 K. The heat rejected is

An ideal gas is flowing through an insulated pipe at the rate of 3.3 kg. There is a pressure drop of 15% from the inlet to the outlet of the pipe. What is the rate of energy loss because of this pressure drop due to friction, given that R_gas= 0.287 kJ/kg K and the reference temperature T0 is 300 K?

A furnace is provided with an insulating refractory lining. The overall thermal conductivity of the material is 0.03 W/mK. The thickness of the lining is 100 mm. The inner and outer temperatures are 250°C and 50°C, respectively. The heat loss to the surroundings will be

A wall of 0.6m thickness has normal area of 1.5 m² and is made up of material of thermal conductivity 0.4 W/mK. If the temperature on the two sides of the wall are 800°C and 1000°C, the thermal resistance of the wall is

Heat is lost from a 100 mm diameter steam pipe placed horizontally in ambient air at 30°C. If the Nusselt number is 25 and the thermal conductivity of the air is 0.03 W/m K, then the heat transfer coefficient will be

Knocking in a spark ignition engine can be reduced by
1. retarding the spark
2. supercharging
3. increasing the engine speed
4. using a fuel of long straight chain structure Select the correct answer using the code given below.

A 4-cylinder diesel running at 1200 r.p.m. developed 18.6 kW. The average torque when one cylinder was cut out was 105 N m. If the calorific value of the fuel was 42000 kJ/kg and the engine used 0.34 kg of diesel/kW hr, the indicated thermal efficiency was nearly

In a Morse test on a 2-cylinder, 2-stroke SI engine, the brake power is 9 kW and the BHP of individual cylinders with spark cutoff are 4.25 kW and 3.75 kW, respectively. The mechanical efficiency of the engine is

Consider the following statements for refrigeration and air-conditioning:
1. In a refrigerating machine, the heat exchanger that absorbs heat is connected to a conditioned space.
2. A refrigerating cycle operating reversibly between two heat reservoirs has the highest coefficient of performance.
3. The lower the refrigeration required and the higher the temperature of heat rejection to the surroundings, the larger the power consumption.
Which of the above statements are correct?

In a refrigerator, the evaporator and condenser coil temperatures are –33°C and 27°C, respectively. Assuming that the maximum COP is realized, the required power input for a refrigerating effect of 4 kW is

Consider the following statements: The volumetric efficiency of a reciprocating compressor can be improved by
1. decreasing the clearance volume
2. cooling the intake air
3. heating the intake air
Which of the above statements is/are correct?

Consider the following statements :
The presence of air inside condensers
1. remains as a non-condensable gas
2. reduces the condensing coefficient
3. tends to cling to the surface
4. introduces large thermal resistance
Which of the above statements are correct?

The refrigeration system of an ice plant working between temperatures of –5°C and 25°C produces 20 kg of ice per minute from water at 20°C. The specific heat of water is 4.2 kJ/kg and latent heat of ice is 335 kJ/kg. The refrigeration capacity of the refrigeration plant is

Consider the following statements in respect of a vapour-absorption refrigeration cycle :
1. The absorption refrigeration cycle is generally used when waste heat is available from an existing source or when free energy like solar energy is to be used.
2. There are no moving parts in the absorption refrigeration plant except a small liquid pump.
3. The value of the coefficient of performance is nearly the same in both vapour-absorption and vapour- compression refrigeration plants.
Which of the above statements are correct?

Air at 30°C and 1 bar has a specific humidity of 0.016 kg/kg of dry air. By considering the saturation pressure of water vapour at 30°C as 4.246 kPa, the relative humidity of the air will be

Consider the following statements in respect of an evaporative cooling process :
1. The wet-bulb temperature remains constant.
2. The dew-point temperature remains constant.
3. The enthalpy remains constant.
Which of the above statements are correct?

Which of the following statements are correct?
1. The specific speed of a turbine is the speed at which a homologous turbine develops 1 mhp under unit heat at its maximum efficiency.
2. The specific speed is a dimensionless parameter used for the selection of turbines.
3.The function of guide vanes in reaction turbines is to minimize shock at entry of the fluid onto the runner blades.
Select the correct answer using the code given below :

A centrifugal pump lifts 0.0125m³/sof water from a well with a static lift of 30 m. If the brake power of the driving electric motor is 5 kW, what is the overall efficiency of the pump-set?

Consider the following statements in respect of ideal and practical gas turbine cycles:
1. In the ideal cycle case, the cycle efficiency depends on the pressure ratio only.
2. In the practical cycle case (with irreversibilities in the compression and expansion processes), The cycle efficiency depends on the maximum temperature as well as on the pressure ratio.
3. In the practical cycle case, at a given maximum temperature, the maximum efficiency and the maximum work done occur at a same pressure ratio.
Which of the above statements are correct?

A jet of water issues from a sharp-edged vertical orifice under a constant heat of 0.51 m. At a certain point of the issuing jet, the horizontal and vertical coordinates measured from vena contracta are 0.406 m and 0.085 m, respectively. What is the value of the coefficient of velocity?

Consider the following statements for single stage reciprocating compressors :
1. Isothermal process is the most desirable process for compression.
2. The size of clearance volume provided in the compressor has no effect on work done per kg of air delivered.
3. The volumetric efficiency of the compressor decreases with increasing pressure.
Which of the above statements are correct?

Consider the following statements in respect of regenerative Rankine cycle:
1. Regeneration increases the efficiency of the cycle.
2. The boiler capacity is increased for a given output.
3. The capacity of the condenser is reduced.
Which of the above statements are correct?

Volumetric analysis of a certain flue gas gave CO₂ 15%, O₂ 5% and rest as N₂. The gas was at a temperature of 200°C and a pressure of 5 bar. The partial pressure of N₂ in the flue gas is

Consider the following statements:
1. The efficiency of heat transfer in a condenser will improve by increase of the overall heat transfer coefficient.
2. The efficiency of heat transfer in a condenser will improve by increase of the velocity of flow of water in the tube.
3. The difference between the temperature of steam entering the condenser and the inlet water temperature should be maximum for maximum efficiency.
Which of the above statements are correct?

The total power developed by a three stage velocity compounded impulse steam turbine is 900 kW. The power magnitudes developed in the first and the second stages are, respectively

Consider the following statements in respect of natural-draft cooling towers :
1. Theoretically the water can be cooled to even below the dry-bulb temperature of the induced air flow.
2. Natural draft cooling towers are 100 m or more in height.
3. The inner and outer surfaces are surfaces of revolution of a segment of a hyperbola about the vertical axis-affording improved strength rather than any thermodynamic augmentation.
Which of the above statements are correct?

Consider the following statements :
1. Wind velocity at about 20 m height above the ground is taken as the rated velocity for design of windmills.
2. The total power of a wind stream is directly proportional to the cube of average velocity.
3. Wind turbine operates with variable load over a narrow range between cut-in and cut-out velocities.
4. Vertical wind machine operates in all wind directions, but it needs yaw adjustment.
Which of the above statements are correct?

Which fuel cell is suitable for spacecraft applications?

A flywheel on a motor speeds up from rest to 1000 r.p.m. in 6 seconds. The number of revolutions made thereby is nearly :

Two steel balls of 2 kg and 4 kg mass, respectively are pressed on the two ends of a spring, all pre-placed on a smooth surface. When released, the smaller ball moves with an acceleration of 2m/s².The simultaneous acceleration of the bigger ball will be :

A bullet of mass 0.03 kg moving with a speed of 400 m/s penetrates 12 cm into a fixed block of wood. The average force exerted by the wood on the bullet will be:

In the design of beams for a given strength, consider that the conditions of economy of use of the material would avail as follows:
1.Rectangular cross-section is more economical than square section area of the beam.
2. Circular section is more economical than square section.
3. I-section is more economical than a rectangular section of the same depth.
Which of the above are correct?

Which one of the following statements is correct?

A beam of rectangular section (12 cm wide × 20 cm deep) is simply supported over a span of 12 m. It is acted upon by a concentrated load of 80 kN at the midspan. The maximum bending stress induced is:

A uniform bar, simply supported at the ends, carries a concentrated load P at mid-span. If the same load be, alternatively, uniformly distributed over the full length of the bar, the maximum deflection of the bar will decrease by

A thin cylindrical pressure vessel and a thin spherical pressure vessel have the same mean radius, same wall thickness and are subjected to same internal pressure. The hoop stresses set up in these vessels cylinder in relation to sphere) will be in the ratio

A boy walks up a stalled escalator in 90 seconds. When the same escalator moves, he is carried up in 60 seconds. How much time would it take him to walk up the moving escalator?

On completion of heat treatment, the austenite structure would be retained if:

Which of the following statements is correct?

The correct order of increasing resistivity among the following materials is :