Mechanical Engineering

MECHANICAL ENGINEERING

1. An impulse turbine

(A) Makes use of a draft tube

(B) Always operates submerged

(C) Converts the pressure head into velocity head through the vanes

(D) Is most suited for low head installations

2. Power required to drive a centrifugal pump is directly proportional to

(A) Diameter of its impeller

(B) Square of diameter of its impeller

(C) Cube of diameter of its impeller

(D) Fourth power of diameter of its Impeller

3. The locus of the common point on the two meshing spur gears is known as

(A) Addendum circle

(B) Duodenum circle

(C) Pitch circle

(D) Base circle

4. When there is a reduction in amplitude over every cycle of vibration then the body is said to have

(A) Free vibration

(B) Forced vibration

(C) Damped vibration

(D) Natural vibration

5. For machining at high speed the tool material should have

(A) Wear resistance

(B) Red hardness

(C) Toughness

(D) All of these

6. MIG welding is

(A) A gas welding process

(B) An electric resistance welding process

(C) A electric resistance welding process

(D) A forge welding process involving high temperatures and low pressures

7. The ability of sand to permit the metal to shrink when it solidifies is known is

(A) Plasticity (B) Permeability

(C) Collapsibility (D) Cohesiveness

8. Rivets are generally specified by

(A) Overall length

(B) Shank diameter

(C) Thickness of plates to be jointed

(D) Diameter of head

9. Which of the following is steady flow compressor

(A) Reciprocating compressor

(B) Centrifugal compressor

(C) Voot blower

(D) Vane blower

10. A closed cycle gas turbine works on

(A) Carnot cycle (B) Rankine cycle

(C) Brayton cycle (D) Joule cycle

11. Thermal conductivity of solid metals

(A) Decreases with rise in temperature

(B) Does not vary with temperature

(C) Increases with rise in temperature

(D) Remains constant with rise in Temperature

12. During adiabatic saturation process, air property which remains constant, is known as

(A) Wet bulb temperature

(B) Dry bulb temperature

(C) Relative humidity

(D) Specific humidity

13. Bell-Coleman cycle as applied to

refrigeration operates

(A) On open air system

(B) On vapour compression system

(C) On vapour absorption system

(D) On none of these

14. The gears in which axes of the shaft connected by them, intersect, are known as

(A) Spur gears (B) Bevel gears

(C) Spiral gears (D) Gear train

15. Shot peening

(A) Is done at re-crystallization temperature

(B) Changes the crystalline structure at materials

(C) Improves the fatigue life of small parts

(D) Refines the grain structure

16. In a bomb calorimeter the heat released by the fuel is absorbed by

(A) Atmospheric air

(B) Water

(C) Metal container

(D) Bomb, water and metal container

17. Nitriding is done

(A) On low carbon steels only

(B) To impart blue colour to steels

(C) To improve machinability

(D) To increase surface hardness

18. The extent of cold work that a metal can withstand depends on

(A) Purity of metal

(B) Carbon percentage

(C) Ductility

(D) Room temperature

19. Which engine has the highest air fuel ratio

(A) Petrol engine (B) Gas engine

(C) Diesel engine (D) Gas turbine

20. Annealing of steels is done to

(A) Remove internal stresses

(B) Produce soft core under hard surface

(C) Produce hard core under soft surface

(D) Introduce capacity to withstand shocks

General Engineering

GENERAL ENGINEERING

1. The probability of hitting a target from one gun 9/10, from another gun is 7/10. If both gun are fired at the same time, the probability of hitting the target is
(A) 2/20
(B) 63/100
(C) 16/20
(D) 63/20

2. If the three vectors a, b and c are coplanar , then the missed product a x b. c is
(A) Zero
(B) Non-Zero
(C) Unity
(D) None of these

3. When a body hits an obstacle, the force with which it hits the obstacle depends upon its
(A) average velocity
(B) velocity at the instant of collision
(C) initial velocity
(D) all of these

4. The wavelength of visible light is of the order of
(A) 1µm
(B) 100 µm
(C) 1mm
(D) 1 Å

5. Whenever a source of sound moves towards an observer
(A) the frequency heard by the observer is less than that of the source
(B) the frequency heard by the observer is greater than that of the source
(C) the frequency heard by the observer is unchanged
(D) the wavelength of sound heard is greater than that of the sound emitted

6. Moving electric charges will interact with
(A) electric field only
(B) magnetic field only
(C) both of these
(D) none of these

7. Gamma radiation is most similar to
(A) sound waves (B) X-ray
(C) Alpha particles (D) neutrons

8. The fundamental particle responsible for keeping the nucleus together is
(A) meson
(B) anti proton
(C) positron
(D) muon

9. Air contains 21% oxygen by volume and the rest nitrogen. If the barometer pressure is 740 mm of Hg the partial pressure of oxygen is close to
(A) 155 mm of Hg
(B) 310 mm of Hg
(C) 465 mm of Hg
(D) 162 mm of Hg

10. In the electrolytic cell
(A) electrical energy is converted into chemical energy
(B) chemical energy is converted into electrical energy
(C) mechanical energy is converted into potential energy
(D) potential energy is converted into kinetic energy

11. The force required to maintain a body at constant speed in free space is equal to 
(A) the mass of the body
(B) zero
(C) the weight of the body
(D) the force required to stop it

12. If the length of a spring is halved, the spring constant becomes
(A) half
(B) 1/4th
(C) double
(D) four times

13. The coefficient of static friction depends on
(A) the material of the bodies in contact
(B) the quality of surface finish of the bodies
(C) the presence of foreign matter between the surface
(D) all of these

14. The units of angular impulse in SI system are
(A) Nms
(B) Ns
(C) Nm/s
(D) Ns/m

15. Stainless steel contains iron and
(A) Chromium and nickel
(B) Chromium and carbon
(C) Nickel and carbon
(D) Chromium and manganese

16. The property of material by which it offers resistance to scratching or indentation is called
(A) Brittleness
(B) Hardness
(C) Toughness
(D) Resilience

17. The failure of a material due to repeated stressing is known as
(A) Creep
(B) Fracture
(C) Fatigue
(D) Brittle Fracture

18. The electric device which blocks DC but allows AC is called
(A) Capacitor
(B) Inductor
(C) Amplifier
(D) Transducer

19. When a charge is moved from one point to another in an electric field, the work done is
(A) independent of the path
(B) zero along the direction of the field
(C) measured in Joules per metre
(D) measure in Volt per metre

20. A capacitor with lowest leakage is
(A) Paper
(B) Ceramic
(C) Polyester (D) Mica

21. A zener diode operates
(A) In an extremely high forward bias
(B) In an extremely low reverse bias
(C) In an extremely low forward bias
(D) In a reverse bias higher than laid down voltage

22. The specific gravity of a lead acid cell is often used as a measure of its
(A) Rate of discharge
(B) Operating temperature
(C) State of charge
(D) Life expectancy

23. An uniformly distributed load is one which
(A) Acts at a point on a beam
(B) Spreads uniformly over the whole length of a beam
(C) Varies uniformly over the whole length of a beam
(D) loads the beam from one end only

24. A steam engine device which keeps the speed of the engine, all loads, constant is known as
(A) Flywheel
(B) Eccentric
(C) Connecting rod
(D) Governor

25. The refrigerant hiving the lowest freezing point is
(A) Ammonia
(B) Carbon dioxide
(C) Freon – 11
(D) Freon – 22

26. Heat and work are
(A) Path functions
(B) Properties of a substance
(C) Point functions
(D) Absolute units

General Engineering - Solved

1. Two free parallel wires carrying current in the opposite directions

(a) Attract each other

(b) Repel each other

(c) Do not effect each other

(d) Get rotated to be perpendicular to each other

Ans.(b)

2. All the magnetic materials looses their magnetic property when

(a) Dipped in water

(b) Dipped in oil

(c) Brought near piece of iron

(d) Strongly heated

Ans.(d)

3. Potassium paramagnet is used for

(a) Dechlorination

(b) Improving colour

(c) Reducing acidity

(d) Reducing hardness

Ans.(b)

4. Which of the following material has the highest carbon percentage?

(a) Cast iron

(b) Mild steel

(c) High carbon steel

(d) Stainless steel

Ans.(a)

5. Which of the following paints is most fire resistant

(a) Bituminous paint

(b) Asbestos paint

(c) Aluminum paint

(d) Synthetic paint

Ans.(b)

6. The gas which is mainly responsible for the explosion in sewers is

(a) Methane

(b) Ethane

(c) Ammonia

(d) Carbon- monoxide

Ans.(d)

7. The Wind screen of car made of

(a) Sheet glass

(b) Wired glass

(c) Laminated glass

(d) Flint glass

Ans.(c)

8. Which of the welding process is used for welding of structures?

(a) Gas welding

(b) Fusion welding

(c) Thermic welding

(d) Arc welding

Ans.(d)

9. In a d.c generator, following losses will be minimum

(a) Copper loss

(b) Iron loss

(c) Friction loss

(d) Shunt field copper loss

Ans.(b)

10. Corona loss is less when the shape of the conductor is

(a) Circular

(b) Flat

(c) Oval

(d) Independent of shape

Ans.(a)

11. The core of the transformer is assembled with laminated sheet so as to reduce

(a) Hysteresis loss

(b) Copper loss

(c) Magnetic noise

(d) Eddy current loss

Ans.(d)

12. Which of the following instrument is used for measuring the rate of flow of liquid of pipes

(a) Hydro meter

(b) Venturi meter

(c) Viscometer

(d) Falter pump

Ans.(b)

13. The proper use of lubricants cannot reduce

(a) Static friction

(b) Inertia

(c) Sliding friction

(d) Rolling friction

Ans.(b)

14. Infra red radiation can be detected by

(a) Spectrometer

(b) Pyrometer

(c) Nanometer

(d) Photometer

Ans.(b)

15. Which of the following is used in optical fibers

(a) Total internal reflection

(b) Scattering

(c) Diffraction

(d) Refraction

Ans.(a)

16. Metal attains super- conduction properties below the temperature of

(a) 0 deg K

(b) 100 deg C

(c) 100 deg K

(d) 10 deg K

Ans.(d)

17. Powder clinges to the skin because of following property

(a) Adhesion

(b) Cohesion

(c) Surface tension

(d) Capillary action

Ans.(a)

18. The sparking at the brushes in the d.c generator is attributed to

(a) Quick reversal of current

(b) Reactance voltage

(c) Armature reaction

(d) High resistance of the brushes

Ans.(c)

19. D.C series motor should always be started with load because

(a) At no load it will rotate at dangerously high speed

(b) At no load it will not develop high starting torque

(c) It cannot start without load

(d) It draw a small amount of current at no load

Ans.(a)

20. A tunnel diode is

(a) High resistivity p-n junction diode

(b) A slow switching device

(c) An amplifying device

(d) A very heavily doped p-n junction diode

Ans.(d)

21. The effective channel length of a MOSFET in saturation decreases with increase in

(a) Gate voltage

(b) Drain voltage

(c) Source voltage

(d) Body voltage

Ans. (b)

22. The ON voltage and forward breakover voltage of an SCR depends on the

(a) Gate current alone

(b) Band gap of the semiconductor alone

(c) Gate current and the semiconductor band gap respectively

(d) Semiconductor bandgap and the gate current respectively

Ans.(c)

23. Negative feedback in amplifier

(a) Improves the signal to noise ratio at the input

(b) Improves the signal to noise ratio at the output

(c) Does not affect the signal to noise ratio at the output

(d) Reduce the distortion.

Ans.(b)

24. An ideal Op- Amp is an ideal

(a) Voltage controlled current source

(b) Voltage controlled voltage source

(c) Current controlled current source

(d) Current controlled voltage source

Ans.(b)

25. One of the following types of noise becomes of great importance at high frequencies. It is the

(a) Shot noise

(b) Random noise

(c) Impulse noise

(d) Transit- time noise

Ans.(d)

26. Piezoelectricity effect is the polarization of a dielectric under the influence of

(a) Light

(b) Mechanical stress

(c) Electrical stress

(d) Heat

Ans.(b)

27. Entropy of mixture of two gases after sudden mixing is

(a) Greater than

(b) Less than

(c) Same as sum of entropy of individual gases

(d) Unpredictable

Ans.(a)

28. If air filter is removed in a petrol engine, the air/fuel ratio will

(a) Increase

(b) Decrease

(c) Increase and decrease

(d) Remains unchanged

Ans.(a)

29. In a two stage compression , inter -cooling is used for

(a) Reducing work of compression in the first stage

(b) Reducing temperature in the first stage

(c) Reduced work in the second stage

(d) Reducing work and temperature in the second stage

Ans.(d)

30. Which component of refrigeration system controls the flow of refrigerant

(a) Expansion valve

(b) Condenser

(c) Compressor

(d) Evaporator

Ans.(a)

31. Laser beam welding has widest application in

(a) Mass production in heavy industry

(b) Jobbing industry

(c) Electronic industry

(d) Structure and bridge work

Ans.(c)

32. In Equation x-2y+3z=0 and 2x+5y+3z=0, y equals

(a) 0

(b) 1

(c) 2

(d) 3

Ans.(a)

33. If a system of equation has one or more solution it is called

(a) Compatible

(b) Consistent

(c) Homogeneous

(d) Simultaneous

Ans.(b)

34. In a microprocessor the register which holds the address of the next instruction to be fetched is

(a) Accumulator

(b) Program counter

(c) Stack pointer

(d) Instruction register

Ans.(b)

35. The mnemonics used in writing a program is called

(a) Assembly language

(b) Fetch cycle

(c) Microinstruction

(d) Object program

Ans.(a)

36. For which of the following devices, is DMA the most suitable

(a) Keyboard

(b) Mouse

(c) Joy stick

(d) Hard stick

Ans.(d)

37. In real time operating system, which of the following is the most suitable scheduling scheme?

(a) Round robin

(b) First come first served

(c) Random scheduling

(d) Preemptive

Ans.(d)

38. In client –server system , data is usually stored on the

(a) Server

(b) Client

(c) Network

(d) None of the above

Ans.(a)

39. Identify the natural

(a) LISP

(b) PROLOG

(c) Both (a) and (b)

(d) Neither (a) and (b)

Ans.(c)

40. An interrupt that can temporarily ignored by the counter is known as

(a) Vectored interrupt

(b) Non – maskable interrupt

(c) Maskable interrupt

(d) Low priority interrupt

Ans.(c)

Mechanical Engineering- Solved

1. The resultant force acting on a body will be zero if the body

(a) Rotate with uniform deceleration

(b) Rotate with uniform acceleration

(c) Does not rotate

(d) Rotates

Ans: (c)

2. The movement of a force

(a) Occurs about a point

(b) Measures the capacity to do useful work

(c) Occurs only when bodies are in motion

(d) Measures the ability to produce turning or twisting about an axis

Ans: (d)

3. After reaching the yielding stage while testing a mild steel specimen strain

(a) Becomes constant

(b) Strain start decreasing

(c) Increasing without any increase in load

(d) Non of the above

Ans: (c)

4. Volumetric strain for a rectangular of length L, breadth B, and thickness T subjected to a pull of P is given by

(a) e (1-2m)

(b) e (1-2/m)

(c) e (m-2)

(d) e (2/M-1)

Ans: (b)

5. The mechanism used in petrol engine is

(a) Crank mechanism

(b) Slider mechanism

(c) Slider crank mechanism

(d) Natural lines and circular

Ans: (c)

6. M 10 screws have a pitch of

(a) 0.5 mm

(b) 1.25 mm

(c) 2.50 mm

(d) 5.00 mm

Ans: (b)

7. A coarse screw of major diameter 6.00 mm and pitch is designated as

(a) 1x6M

(b) Coarse M 6

(c) M 6

(d) 6Mx6x1

Ans: (c)

8. Longitudinal vibration are set to occur when the particles of a body moves.

(a) Perpendicular to its axis

(b) Parallel to its axis

(c) In a circle about its axil

(d) None of these

Ans: (b)

9. A mass of 1 Kg is attached to the end of a sprig with stiffness 0.7 N/mm.. The critical damping coefficient of the system is

(a) 1.40 Ns/m

(b) 18.522 Ns/m

(c) 52.92 Ns/m

(d) 529.20 Ns/m

Ans: (c)

10. An ideal fluid is

(a) Similar to a perfect gas

(b) Friction less and incompressible

(c) One which obeys Newtons laws of viscosity

(d) One which satisfies continuity equation

(e) One which flows through pipes with least friction

Ans: (b)

11. The stress Strain relation of the Newtonian fluids is

(a) Linear

(b) Parabolic

(c) Hyperbolic

(d) Involutic

Ans: (a)

12. The Reynolds No. may be defined as the ration of

(a) Viscous forces to inertial forces

(b) Elastic forces to pressure forces

(c) Viscous forces to gravity forces

(d) None of the above

Ans: (d)

13. All heat transfer processes

(a) Involve transfer of energy

(b) Involve temperature difference between the bodies

(c) Obeys the first law of the thermodynamics

(d) Obeys second law of thermodynamics

Ans: (b)

14. Which insulating material is a suitable low temperature application?

(a) Cork

(b) Asbestos paper

(c) Diatomaceous earth

(d) 85 % magnesia

Ans: (c)

15. A heat exchanger that can remove fix quantity of heat form a system is available where should it be installed for best economy

(a) Prior to first stage compression

(b) As intercooler

(c) After final stage compression

(d) Depends upon size of installation

Ans: (a)

16. The performance of air compressor at high altitudes as compared to that at sea level will be

(a) Better

(b) Same

(c) Inferior

(d) Will depend upon temperature of air

Ans: (c)

17. Which is incorrect?

(a) Compression ration= Initial volume +final Volume

(b) Final pressure= Initial Pressure x Compression ration

(c) Initial pressure= Final pressure+Compression ration

(d) None of the above

Ans: (d)

18. During adiabatic compression

(a) No heat leaves or enters the system

(b) Maximum work is done

(c) Specific heat remains constant

(d) Temperature remains constant

Ans: (a)

19. In multistage turbines by introducing reheating

(a) Thermal efficiency improves

(b) The output of turbine increases

(c) Work done by compressor reduces

(d) The ratio compressor work/turbine decreases

Ans: (a)

20. In Jet engine the compression ration

(a) Varies with altitude

(b) Varies with square of speed

(c) Varies as cube of speed

(d) remains constant

Ans: (b)

21. An axial flow compressor has

(a) Larger blade at gas entry and smaller blades at exit

(b) Smaller blade at gas entry and larger blades at exit

(c) Identical blades at exit as well as entry

(d) Size of blades remains same only angles changes

Ans: (a)

22. An axial flow compressor is suitable for

(a) High volume flow rates with a small pressure rise

(b) High volume flow rate with high pressure rise

(c) Low volume flow rates with low pressure rise

(d) Low volume flow rates with high pressure rise

Ans: (c)

23. Thermal efficiency of a gas turbine cycle can be improved by

(a) Reheating between the expansion stage

(b) Intercooling between compression stages

(c) Regeneration

(d) Any of the above

Ans: (d)

24. Gas turbine used in aircraft is of

(a) Open cycle type

(b) Closed cycle type with reheating

(c) Closed cycle type with reheating and regeneration

(d) Open cycle type with reheating, regeneration and intercooling

Ans: (a)

25. In a nozzle under choked flow conditions pressures waves travel, in the divergent portion, at

(a) Subsonic speed

(b) Sonic speed

(c) Super sonic

(d) Subsonic to supersonic speed

Ans: (b)

26. In a nozzle if back pressure is equal to inlet pressure

(a) No flow occurs

(b) Maximum flow occurs

(c) Flow is subsonic in diverging section

(d) Flow is supersonic in convergent section as well as supersonic section

Ans: (b)

27. The flow on two sides of a normal shock wave is

(a) Subsonic

(b) Sonic

(c) Supersonic

(d) Supersonic on one side and subsonic on the other side

Ans: (d)

28. The diverging portion of the nozzle acts as a diffuser for

(a) Subsonic flow

(b) Supersonic flow

(c) Both the subsonic as well as supersonic flow

(d) None of the above

Ans: (a)

29. Identify the correct statement

(a) All materials undergo plastic deformation

(b) A completely brittle material would not fracture at elastic limit

(c) Brittleness is an important engineering consideration, because it allows the material to be redistribute localize stresses.

(d) A metal which is brittle in tension may be ductile under hydro static compression

Ans: (d)

30. The defect responsible for the phenomenon of slip by which most metals deform plastically, is known as

(a) Fracture

(b) Twining

(c) Dislocation

(d) Strain hardening

Ans: (c)

31. Fatigue failure occurs when a part is subjected to

(a) Tensile stress

(b) Compressive stress

(c) Torsion

(d) Fluctuating stress

Ans:(d)

32. Stress concentration occurs when

(a) A body is subjected to excessive stress

(b) A body is subjected to unidirectional stress

(c) A body is subjected to fluctuating stress

(d) A body is subjected to non uniform stress distribution

Ans: (d)

33. Stress concentration may be caused by

(a) Change in cross sectional area

(b) Change in shape

(c) Change in dimension

(d) A hole or a notch in the body

Ans:(d)

34. The inability of a body to change its state of rest or uniform motion along a straight line is called its

(a) Momentum

(b) Velocity

(c) Acceleration

(d) Inertia

Ans: (d)

35. A material subjected to reversal of stresses does not fail at a stress known as

(a) fatigue stress

(b) Proof stress

(c) Safe stress

(d) Endurance stress

Ans: (d)