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Mechanical Engineering

In first-angle projection, the top view is placed:

Hidden edges on a machine drawing are shown by:

The throat thickness of a fillet weld of leg size s is:

According to Unwin's formula, rivet diameter d (mm) for plate thickness t (mm) is:

The efficiency of a riveted joint is the ratio of:

A double-start thread has a pitch of 2 mm. Its lead is:

The thread best suited for a bench vice, where heavy axial force acts in one direction, is:

A key which transmits torque only by friction is the:

A key that permits axial movement of the hub along the shaft is the:

The difference between the minimum size of a hole and the maximum size of the mating shaft is called:

The fit H7/p6 is an example of:

On a surface-texture symbol, a horizontal bar added to the basic tick means:

Interchangeability of parts in mass production is achieved mainly by:

As the tolerance specified on a component is made tighter, the manufacturing cost generally:

The property that allows a metal to be drawn into wires is:

The energy absorbed by a material up to the elastic limit is called:

In a Vickers hardness test, the indenter is a:

In the Izod impact test, the specimen is held as a:

Duralumin is an alloy of aluminium mainly with:

Brass is an alloy of:

The minimum chromium content for a steel to be called stainless is about:

Fatigue failure occurs under:

Which process improves fatigue strength by inducing compressive residual stress?

The creep stage used as the basis for design is:

In galvanic corrosion between zinc and steel, the metal that corrodes is:

Dezincification of brass is an example of:

Testing of a welded pressure vessel without damaging it is carried out by:

Value analysis of a component mainly aims to:

The number of atoms per unit cell in an FCC structure is:

The atomic packing factor of a BCC structure is:

γ-iron (austenite) has which crystal structure?

In an edge dislocation, the Burgers vector is:

According to Gibbs' phase rule at constant pressure, the degrees of freedom at the eutectic point of a binary alloy are:

The reaction Liquid + Solid α → Solid β on cooling is called:

The eutectoid composition in the iron-carbon diagram is about:

Pearlite is a lamellar mixture of:

The hardest micro-constituent obtained by rapid quenching of steel is:

In spheroidal graphite (ductile) cast iron, graphite nodules are produced by adding:

Which of the following is a thermosetting plastic?

According to the Hall-Petch relation, decreasing grain size:

Annealing is often carried out between stages of deep drawing in order to:

Replacing several machined metal parts by a single injection-moulded plastic part is attractive mainly when:

Kirchhoff's Voltage Law is based on the conservation of:

Two 10 Ω resistors connected in parallel have an equivalent resistance of:

The form factor of a sinusoidal wave is:

In a star-connected three-phase system, line voltage equals:

The synchronous speed of a 4-pole, 50 Hz induction motor is:

A 4-pole, 50 Hz induction motor runs at 1440 rpm. Its slip is:

The DC motor best suited for electric traction and cranes is the:

The direction of induced EMF in a generator is found by:

A transformer has maximum efficiency when:

Transformer cores are laminated mainly to reduce:

A Zener diode is mainly used as a:

For a BJT with α = 0.98, the current gain β is:

Power-factor improvement capacitors are installed in an industrial plant mainly to:

Fitting a variable-frequency drive to a centrifugal pump saves energy because pump power varies approximately as:

While operating a lathe or drilling machine, the operator should NOT:

The correct extinguisher for a fire on live electrical equipment is:

A micrometer with 0.5 mm pitch and 50 thimble divisions has a least count of:

In a lathe, the lead screw is used for:

The cutting speed when turning a 50 mm diameter bar at 200 rpm is approximately:

Long, gentle tapers on a lathe are best produced by:

The quick-return mechanism is used in a:

In down (climb) milling, the cutter rotates:

Number of crank turns on a dividing head (40:1) to cut a 20-tooth gear is:

For grinding a very hard material, the wheel should be:

The standard point angle of a general-purpose twist drill is:

In DC arc welding with straight polarity (DCSP), the electrode is connected to the:

The oxy-acetylene flame used for welding brass is:

A bar is turned over a length of 300 mm at a feed of 0.2 mm/rev and 500 rpm. The machining time is:

The main industrial-engineering benefit of using jigs and fixtures is:

An organisation structure in which an employee reports to two bosses is:

Functional organisation was introduced by:

Who is known as the father of modern (administrative) management theory?

The Hawthorne experiments are associated with:

Management by Objectives (MBO) was popularised by:

In Blake and Mouton's Managerial Grid, the ideal (team management) style is:

The informal channel of communication in an organisation is called:

According to Herzberg, salary and working conditions are:

The highest level need in Maslow's hierarchy is:

Selection in HRM is generally called a negative process because it:

Fixed cost Rs 50,000, selling price Rs 25/unit, variable cost Rs 15/unit. Break-even quantity is:

An information system that integrates finance, HR, production and sales on a common database is:

The Delphi method is used for:

Time study, standardisation of tools and methods, and the differential piece-rate system were introduced by:

According to Herzberg's two-factor theory, salary and working conditions are:

A system that allows both mass and energy to cross its boundary is:

Which of the following is an intensive property?

Heat and work are:

The zeroth law of thermodynamics forms the basis of:

The temperature at which Celsius and Fahrenheit scales read the same value is:

The value of the universal gas constant is:

For air, cp = 1.005 kJ/kg·K and cv = 0.718 kJ/kg·K. The gas constant R is:

A real gas behaves most like an ideal gas at:

Dryness fraction of dry saturated steam is:

Wet steam at a pressure where hf = 500 kJ/kg and hfg = 2200 kJ/kg has x = 0.9. Its enthalpy is:

At the critical point of water, the latent heat of vaporisation is:

The Mollier chart is a plot of:

Specific energy consumption of a plant is normally expressed as:

One kilowatt-hour of energy is equal to:

For a closed system, the first law of thermodynamics is expressed as:

For an ideal gas, internal energy is a function of:

In a constant-volume process, the work done is:

In an isothermal process of an ideal gas, the change in internal energy is:

The polytropic index n for a reversible adiabatic process is:

0.5 m³ of air at 1 bar is compressed isothermally to 0.1 m³. The work done (magnitude) is approximately:

During a throttling process, which property remains constant?

Steam enters a nozzle with negligible velocity and an enthalpy drop of 100 kJ/kg. The exit velocity is about:

In an adiabatic steam turbine with negligible KE and PE changes, work output per kg equals:

A perpetual motion machine of the first kind violates:

Air is freely expanded into an insulated vacuum. For the air:

When an evacuated, insulated rigid tank is filled with an ideal gas from a supply line at Tline, the final gas temperature is:

The indirect (heat-loss) method of finding boiler efficiency is preferred because it:

An economiser in a boiler plant recovers waste heat to:

The Kelvin-Planck statement implies that:

A perpetual motion machine of the second kind violates:

A Carnot engine works between 527 °C and 27 °C. Its efficiency is:

The Carnot cycle consists of:

The efficiency of a Carnot engine depends on:

A refrigerator operates between −3 °C and 27 °C. Its maximum (Carnot) COP is:

For the same temperature limits, COP of a heat pump is related to COP of a refrigerator by:

Which of the following is NOT a cause of irreversibility?

For an irreversible cycle, the Clausius inequality gives ∮δQ/T:

The entropy of an isolated system undergoing a real process:

An isentropic process is:

Isentropic efficiency of a compressor is defined as:

One tonne of refrigeration is equal to:

Cogeneration (combined heat and power) raises overall energy utilisation because it:

The Otto cycle consists of two isentropic processes and two:

The air-standard efficiency of an Otto cycle with r = 8 and γ = 1.4 is approximately:

For the same compression ratio and heat input, the most efficient cycle is:

For the same maximum pressure and temperature, the most efficient cycle is:

The efficiency of a Diesel cycle, for a fixed compression ratio, increases when:

The Brayton cycle is the ideal cycle for:

The efficiency of an ideal Brayton cycle depends on:

In a Rankine cycle, the process in the condenser is:

Reheating in a Rankine cycle is mainly used to:

In a vapour compression refrigeration cycle, the expansion process is:

One ton of refrigeration is equal to about:

In a lithium bromide–water absorption system, the refrigerant is:

A back-pressure steam turbine is used in industry mainly to:

A vapour-absorption refrigeration system is attractive in a plant that has:

In a four-stroke engine, the number of power strokes per revolution of the crankshaft is:

The camshaft of a four-stroke engine rotates at:

In a CI engine, fuel is ignited by:

The typical compression ratio of a diesel engine is:

Load in an SI engine is controlled by varying the quantity of mixture using the throttle. This is called:

The anti-knock quality of petrol is expressed by:

To reduce knocking in a CI engine, one should:

Engine swept volume 500 cc and clearance volume 50 cc. The compression ratio is:

An engine has IP = 50 kW and BP = 40 kW. Its mechanical efficiency is:

In a two-stroke petrol engine, the ports are opened and closed by:

The component that converts reciprocating motion of the piston to rotary motion is the:

The function of a flywheel in an IC engine is to:

A diesel generating set gives its best specific fuel consumption when loaded to about:

In selecting the rating of a DG set for a factory, the most important additional consideration beyond the running load is:

Summer air-conditioning generally involves:

In a fire-tube boiler:

Which of the following is a water-tube boiler?

The Benson boiler is characterised by:

An economiser in a boiler is used to:

Which of the following is a boiler mounting (not an accessory)?

For minimum work in a two-stage air compressor with perfect intercooling, compressing from 1 bar to 16 bar, the intermediate pressure is:

The work required for compressing air is minimum when compression is:

Refrigerant R-717 is:

R-134a replaced R-12 mainly because R-134a has:

For saturated air:

During evaporative cooling (desert cooler), which remains approximately constant?

Specific humidity of moist air is given by:

In a compressed-air system, reducing the compressor discharge pressure by 1 bar typically saves about:

Humidity control is essential in a textile spinning mill mainly because:

A fluid is a substance that:

The no-slip condition states that at a solid wall the fluid:

The Eulerian method of describing fluid flow:

One poise is equal to:

With an increase in temperature, the viscosity of a liquid:

Blood and paints are examples of:

A fluid which requires a minimum yield stress before it flows, like toothpaste, is a:

The excess pressure inside a soap bubble of diameter d is:

Mercury in a clean glass capillary tube shows:

Standard atmospheric pressure is equivalent to a water column of about:

A piezometer cannot be used to measure:

For a vertical rectangular gate of depth d with its top at the free surface, the centre of pressure is at depth:

A fluid such as sewage sludge or toothpaste, which needs a minimum shear stress before it begins to flow, is called a:

A rising differential pressure across an industrial filter or bag house indicates that:

A flow in which velocity at a point does not change with time is called:

Flow through a long straight pipe of constant diameter at a constant rate is:

Reynolds number is the ratio of:

Flow in a circular pipe is generally laminar when the Reynolds number is less than about:

Water (ν = 1 × 10⁻⁶ m²/s) flows at 0.1 m/s in a 10 mm pipe. The flow is:

Air flow may be treated as incompressible when the Mach number is less than about:

The line traced by dye injected continuously at a fixed point in a flow is a:

In steady flow, streamlines, pathlines and streaklines:

The stream function ψ exists for:

The velocity potential function exists only when the flow is:

Streamlines and equipotential lines intersect each other at:

In a free vortex flow, velocity varies with radius as:

Turbulent flow is generally desirable in a heat exchanger because it:

Sudden closing of a valve in a long water pipeline causes:

Bernoulli's equation is based on the conservation of:

Which is NOT an assumption of Bernoulli's equation?

Water flows from a 200 mm pipe into a 100 mm pipe. If velocity in the larger pipe is 1 m/s, velocity in the smaller pipe is:

The coefficient of discharge of a venturimeter is about:

A pitot tube is used to measure:

The theoretical velocity of a jet from an orifice under a head of 5 m is about:

For a sharp-edged orifice, Cd = Cc × Cv is approximately:

Discharge over a triangular notch is proportional to:

The force exerted by a jet on a stationary flat plate held normal to it is:

According to Buckingham's π-theorem, a problem with 7 variables and 3 fundamental dimensions has:

Ship models and spillway models are designed using:

In a Froude-scaled model with length ratio 1:25, the discharge ratio (model/prototype) is:

Compared with an orifice plate, a venturi meter has:

The flow meter that measures mass flow rate directly and is used for costly process fluids is the:

For laminar flow in a circular pipe, the maximum velocity is:

The friction factor for laminar flow in a pipe at Re = 1600 is:

In laminar pipe flow, the shear stress is:

According to Hagen-Poiseuille, for a given pressure drop the discharge through a pipe varies as:

For laminar flow between two fixed parallel plates, umax/Vavg is:

The Darcy-Weisbach equation gives head loss as:

For pipes connected in parallel:

The head loss due to sudden expansion from velocity V1 to V2 is:

Power transmitted through a pipe is maximum when the friction head loss equals:

Boundary layer thickness is the distance from the wall where velocity reaches:

For a laminar boundary layer on a flat plate, thickness varies with distance x as:

Flow separation occurs when:

Controlling the flow of a centrifugal pump by throttling a discharge valve is inefficient because it:

Frictional head loss in a pipe carrying a given fluid varies approximately with:

A Pelton wheel is a:

A Kaplan turbine is best suited for:

Which turbine is most suitable for a head of 500 m?

The specific speed of a turbine is given by:

In a Pelton wheel, the flow of water is regulated by:

The function of the casing of a Pelton wheel is to:

In a Francis turbine, the guide vanes (wicket gates) serve to:

Double regulation (adjustable guide vanes and runner blades) is a feature of the:

The main function of a turbine governor is to:

Cavitation in a reaction turbine is most likely at the:

A draft tube is used in:

The cone angle of a conical draft tube should not exceed about:

The turbine most widely used in Nepali micro-hydro schemes because it is simple and can be made locally is the:

Cavitation in a hydraulic machine occurs when the local pressure falls:

A centrifugal pump works on the principle of:

The most commonly used impeller blade shape in centrifugal pumps is:

Priming of a centrifugal pump is necessary because:

Which pump does NOT require priming?

A centrifugal pump should be started with the delivery valve:

To avoid cavitation in a pump:

Which action INCREASES the available NPSH?

If the speed of a centrifugal pump is doubled, the head developed becomes:

If pump speed is doubled, the power required becomes:

Two identical pumps connected in parallel will:

The specific speed of a pump is given by:

Negative slip in a reciprocating pump means:

According to the affinity laws, if the speed of a centrifugal pump is reduced to half, the power required becomes about:

A pump running far away from its best efficiency point typically suffers:

The principle of transmissibility of forces is applicable to:

Lami's theorem applies to:

The moment of a couple about any point in its plane is:

A hinged (pin) support in a 2-D structure provides:

Two forces of 3 N and 4 N act at right angles. Their resultant is:

The angle of repose is equal to:

The force of friction between two dry surfaces is:

D'Alembert's principle converts a dynamic problem into:

The maximum horizontal range of a projectile is obtained when it is projected at:

The work-energy theorem states that the net work done on a body equals the change in its:

A ball dropped from 4 m rebounds to 1 m. The coefficient of restitution is:

In a perfectly plastic collision, the coefficient of restitution is:

The tension ratio of a flat belt about to slip on a pulley is given by:

As the included angle between two sling legs lifting a load increases, the tension in each sling:

Hooke's law is valid up to the:

A steel bar 2 m long, area 100 mm², carries 20 kN. With E = 200 GPa, the elongation is:

The elongation of a bar hanging under its own weight W is:

A bar is fully restrained and heated by ΔT. The thermal stress is:

The theoretical maximum value of Poisson's ratio for an isotropic material is:

The relation between E, G and μ is:

If E = 200 GPa and μ = 0.25, the modulus of rigidity G is:

Volumetric strain of a rectangular bar subjected to axial load P is:

For a material with Poisson's ratio 0.5, the bulk modulus is:

The strain energy stored in a bar under axial load P is:

The maximum stress due to a suddenly applied load compared to the same load applied gradually is:

Modulus of resilience is:

A load applied suddenly (but without impact velocity) produces a stress approximately:

The factor of safety used for lifting equipment such as chains and slings is usually:

The centroid of a triangle of height h lies at a distance from its base of:

The centroid of a semicircular area of radius r from its diameter is:

The moment of inertia of a rectangle b × d about its base is:

The polar moment of inertia of a solid circular shaft of diameter d is:

Bending moment in a beam is maximum where the shear force:

A simply supported beam of span L carries a UDL w. The maximum bending moment is:

A cantilever of length L carries a point load W at the free end. The maximum deflection is:

The maximum deflection of a simply supported beam with a central point load W is:

For a rectangular beam section, the maximum shear stress is:

A plane truss with j joints is perfect if the number of members m is:

The maximum shear stress in a solid shaft of diameter d transmitting torque T is:

A shaft subjected to bending moment M and torque T has an equivalent torque of:

A shaft transmitting 15 kW at 300 rpm carries a torque of about:

The load capacity of a pallet-rack beam is often limited not by stress but by:

Which of the following is a higher pair?

A kinematic chain becomes a mechanism when:

According to Kutzbach's criterion, a planar linkage with 4 links and 4 binary lower pairs has DOF:

A planar linkage has 5 links and 6 binary joints. Its degree of freedom is:

Grashof's law for a four-bar chain having at least one fully rotating link is:

The Whitworth quick-return mechanism is an inversion of the single slider-crank chain obtained by fixing the:

An elliptical trammel is an inversion of the:

The number of instantaneous centres in a six-link mechanism is:

Kennedy's theorem states that the three instantaneous centres of three bodies in relative motion:

The Coriolis component of acceleration is present in:

Oldham's coupling is used to connect two shafts that are:

The Ackermann steering gear is preferred over the Davis steering gear because it:

The mechanism that gives a very large mechanical advantage near the end of its stroke, used in presses and clamping devices, is the:

The quick-return motion of a shaper is obtained from a:

The gyroscopic couple on a body spinning with angular velocity ω and precessing with ωp is:

A ship's rolling motion produces:

The function of a governor is to:

A governor is said to be isochronous when:

The height of a Watt governor running at 60 rpm is approximately:

The maximum fluctuation of energy in a flywheel is:

For complete dynamic balancing of several rotating masses in different planes:

The frequency of the secondary unbalanced force of a reciprocating engine is:

For high-speed cams, the preferred follower motion is:

In a cross-belt drive, the driven pulley rotates:

Power transmitted by a belt is maximum when centrifugal tension equals:

A gear train in which the first and last gears are on the same axis is a:

The standard pressure angle of modern involute gears is:

A flywheel is fitted to a punching press mainly to:

A worm gear reducer used for continuous duty is often avoided in energy-saving projects because:

On principal planes, the shear stress is:

The maximum shear stress planes are inclined to the principal planes at:

For σx = 80 MPa, σy = 20 MPa and τxy = 40 MPa, the maximum principal stress is:

In a state of pure shear τ, the principal stresses are:

The theory of failure most suitable for brittle materials is:

According to the von Mises (distortion energy) theory, the shear yield strength is:

Which of the following is statically indeterminate?

The effective length of a column with both ends fixed (actual length L) is:

In a thin cylindrical shell under internal pressure, hoop stress is:

A cylinder is treated as thin when its wall thickness is less than about:

In a thick cylinder under internal pressure, the maximum hoop stress occurs at the:

For a rectangular shaft under torsion, the maximum shear stress occurs at the:

In a thin cylindrical pressure vessel, the hoop stress is:

Replacing an open channel section of a machine frame by a closed box section mainly improves its:

Which pattern allowance is negative?

Draft allowance is provided on patterns to:

Low permeability of moulding sand mainly causes:

Chaplets in a mould are used to:

The sprue in a gating system is tapered downwards to:

According to Chvorinov's rule, solidification time is proportional to:

Grey cast iron is usually melted in a:

Turbine blades and jewellery are generally produced by:

Hot-chamber die casting is suitable for:

Cast iron pipes are best produced by:

A casting defect caused when two streams of metal meet but fail to fuse is:

Hot tears in castings are mainly caused by:

In full annealing, steel is cooled:

Normalising differs from annealing mainly in that the steel is:

The structure obtained by quenching steel from the austenitic range is:

The purpose of tempering hardened steel is to:

Hardenability of steel is measured by the:

Austempering produces a structure of:

Which case-hardening process does NOT require quenching after treatment?

Cyaniding is carried out in a bath of:

Carburising is generally applied to:

Induction hardening depth is reduced by:

In powder metallurgy, sintering is done at a temperature: