In a differential manometer a head of 0.6m of fluid A in limb 1 is found to balance a head of 0.3m of fluid B in limb 2. The ratio of specific gravities of A to B is

At x = 0, the function f (x) = |x| will be

The center of pressure of a plane submerged surface

A piece of metal of specific gravity 7 floats in mercury of specific gravity 13.6, what fraction of its volume is under mercury?

A right circular cylinder, open at the top, is filled with a liquid of specific gravity 1.2, and rotated about its vertical axis at such a speed that half of the liquid spills out. The pressure at the center of the bottom is

Consider the following statements about velocity potential:
1.Velocity potential is a vector function similar to stream function
2.It is a fully three dimensional function and not limited to two
coordinates
3.Velocity potential does not exist at stagnation points
4.Velocity potential exists only if the flow is irrotational 
Which of the above statements are correct? 

Principle mechanism of material removal in ECM?

In flow through a pipe, the transition from laminar to turbulent flow does not depend on

A 0.20m diameter pipe 20m long transports oil at a flow rate of0.01m³/s. Calculate power required to maintain flow if dynamic viscosity and density of oil is 0.08 Pas and 900 kg/m³ respectively

Pressure loss for laminar flow through pipeline is dependent

Fanno line is a flow in a constant area duct 

In an adiabatic flow with friction through a constant area duct, the following phenomenon are predicted:
1.The flow downstream tends to be sonic irrespective of the Mach-number upstream
2.In the case of initially supersonic flow, any increase in duct length beyond choked flow would make the exit flow subsonic
3.In the case of initially subsonic flow, any increase in duct length will not change sonic flow at the exit
4.The optimum pipe length for sonic outlet in supersonic flow is considerably longer than that of subsonic flow for the same flow rate 
Which of these are correct? 

In a reciprocating pump, air vessels are used to

Consider the following statements pertaining to centrifugal pumps:
1.The inlet to the impeller of a centrifugal pump is always axial, while the outlet may be radial or inclined.
2.The impeller may be shrouded on both sides with an eye at the centre and vanes curved backwards.
3.Impeller of double entry type has a balanced radial thrust.
4.Un-shrouded and part shrouded impeller are used only where high efficiency is unimportant. 
Which of these statements are correct? 

A centrifugal pump is fully primed, but on starting it fails to deliver fluid. Thr probable reasons are listed below:
1.Leaky foot valve or suction line
2.Suction head is very slow
3.Insufficient motor speed
4.Damaged or closed delivery valve 
Which of these reasons are correct? 

A centrifugal pump is to discharge 0.118 m³/s at speed of 1450 rpm against a head of 25m. The impeller diameter is 25cm, its width at outlet is 5cm and manometric efficiency is 75%. The vane angle at outer periphery of impeller is

A turbine is working under a head of 200m. The power developed by the turbine is 100kW and discharge through the turbine is 0.125 m³/s. In such case, the ratio of unit power to unit discharge for the turbine will be

Two geometrical similar pumps are running at 1000 rpm speed (both). If one pump has impeller diameter of 0.3m and discharges 20Ips against 20m head, and the other pump gives half of this discharge rate; calculate head and diameter of second pump

Frictional losses in the nozzle

In a nozzle designed for maximum discharge conditions, the flow velocity in the convergent section of the nozzle is

In the centrifugal compressor, the work input is equal to the sum of

For a centrifugal compressor with radial vanes, slip factor is the ratio of

The specific speed of a centrifugal compressor is generally

In a centrifugal compressor, the highest Mach number leading to shock wave in the fluid flow occurs at

The rating of the fuse wire is always expressed in

In an axial flow compressor, the ratio of pressure rise in the rotor blades to the pressure rise in the compressor in one stage is known as

CNC machine interpolator controls

If a row interchanged in the matrix, then the  determinant of matrix is

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
 

A body of mass 20kg falls freely in vacuum. It has fallen through a vertical distance of 50m. The gravitational acceleration may be assumed as 10m/s². What is the thermodynamic work done by the body?

A closed gaseous system undergoes a reversible constant pressure process at 2bar in which 100 kJ of heat is rejected and the volume changes from 0.2m³ to 0.1m³. The change in the internal energy of the system is

A Carnot engines receives 100kJ of heat at 600K. Heat is rejected at 300K. The displacement volume is 0.2 m³. The mean effective pressure is

The ratio of static enthalpy rise in the rotor to the static enthalpy rise in the stage of an axial flow compressor is defined as:

The eigen values of a symmetric matrix are all

During a thermodynamic process, 100kJ of heat is transferred from a reservoir at 800K to a sink at 400K. The ambient temperature is 300K. the loss of available energy is

The vapor pressure of a liquid at any arbitrary temperature can be estimated approximately with the help of

In order to determine the quality of wet steam by a separating and throttling calorimeter, the steam should be first separated and then throttled such that the final state is

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?

The tendency of detonation is high in engines of larger cylinder diameter because of

An open cycle pressure gas turbine uses a fuel of calorific value 40,000 kJ/kg with airfuel ratio of 80 : 1 and develops a net output of 80kJ/kg of air. The thermal efficiency of the cycle is

Consider the following statements regarding cycles:
1.Stirling cycle consists of two isothermal and two adiabatic processes.
2.In vapor compression cycle, the refrigerant is in form of dry saturated vapor before entering compressor.
3.Diesel cycle consists of one constant pressure; one constant volume and two isentropic processes 
Which of the above statements are correct? 

The efficiency of vapor power Rankine cycle can be increased by
1 .Increasing the temperature of the working fluid at which heat is added
2.Increasing the pressure of the working fluid at which heat is added
3.Decreasing the temperature of the working fluid at which heat is rejected 
Which of the above statements are correct? 

The velocity of a gas flowing through a duct is 300 m/s; its temperature is 127°C; Gas constant R = 0.25 kJ/kg K, the ratio of specific heat is C_p/C_V = 𝛾 = 1.6. What is the value of Mach number?

When a system is taken from state ‘x’ to state ‘y’, 30kJ of heat flows into the system and the system does 10kJ of work. When the system is returned from ‘y’ to ‘x’ along another path, work done on the system is 8kJ. What is the amount of heat liberated or absorbed?

The values of heat transfer and work transfer for the processes of a thermodynamic cycle are given below:
Process                         Heat transfer                          Worktransfer
                                                (kJ)                                      (kJ) 
1                                        300                                          300
2                                         0                                             250
3                                      -100                                           -100
4                                       0                                               -250
The thermal efficiency of the cycle and the work ratio will be respectively

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 :