Mechanical objective questions

ENGINEERING MECHANICS
1.The friction experienced by a body, when in motion, is known as
A.rolling friction
B. dynamic friction
C.limiting friction
D.static friction
2.Two balls of equal mass and of perfectly elastic material are lying on the floor. One of the ball
with velocity v is made to struck the second ball. Both the balls after impact will move with a
velocity
A. v B. v/2
C. v/4 D. v/8
3.The term 'force' may be defined as an agent which produces or tends to produce, destroys or
tends to destroy motion.
A. Agree B. Disagree
4.The velocity ratio in case of an inclined plane inclined at angle θ to the horizontal and weight
being pulled up the inclined plane by vertical effort is
A. sin θ
B. cos θ
C. tan θ
D. cosec θ
5.The range of projectile on a downward inclined plane is __________ the range on upward
inclined plane for the same velocity of projection and angle of projection.
A. less than
B. more than
C. equal to
6.The angle of inclination of a vehicle when moving along a circular path __________ upon its mass.
A. depends
B. does not depend
7.A body of weight W is required to move up on rough inclined plane whose angle of inclination with
the horizontal is α. The effort applied parallel to the plane is given by(where μ = tanφ = Coefficient of
friction between the plane and the body.)
A. P = W tanα
B. P = W tan(α + φ)
C. P = W (sinα + μcosα)
D. P = W (cosα + μsinα
8.If the resultant of two equal forces has the same magnitude as either of the forces, then the angle
between the two forces is
A. 30° B. 60°
C. 90° D. 120°
9.A smooth cylinder lying on its convex surface remains in __________ equilibrium.
A. stable B. unstable
C. neutral
10.Coefficient of friction is the ratio of the limiting friction to the normal reaction between the two
bodies.
A. Yes B. No

11.Moment of inertia of a circular section about an axis perpendicular to the section is
A. πd3
/16 B. πd3
/32
C. πd4
/32 D. πd4
/64
12.The time of flight (t) of a projectile on an upward inclined plane is(where u = Velocity of
projection, α = Angle of projection, and β = Inclination of the plane with the horizontal.)
A.
B.
C.
D.
13.The unit of angular acceleration is
A. N-m B. m/s
C. m/s2
D. rad/s2
14.Moment of inertia of a triangular section of base (b) and height (h) about an axis passing through
its C.G. and parallel to the base, is
A. bh3
/4 B. bh3
/8
C. bh3
/12 D. bh3
/36
15.If the masses of both the bodies, as shown in the below figure, are reduced to 50 percent, then
tension in the string will be
A. same B. half
C. double
16.Which of the following is an equation of linear motion?(where, u and v = Initial and final velocity
of the body, a = Acceleration of the body, and s = Displacement of the body in time t seconds.)
A. v = u + a.t
B. s = u.t + 1/2 a.t2
C. v2
= u2
+2a.s
D. all of these
17.If a number of forces are acting at a point, theirresultant will be inclined at an angle θ with the
horizontal, such that
A. tan θ = ∑H/∑V
B. tan θ = ∑V/∑H
C. tan θ = ∑Vx∑H
D.

18.
The above figure shows the two equal forces at right angles acting at a point. The value of force
R acting along their bisector and in opposite direction is
A. P/2
B. 2P
C.
D.
19.The force required to move the body up the plane will be minimum if it makes an angle with
the inclined plane __________ the angle of friction.
A. equal to
B. less than
C. greater than
20.In the shown figure, if the angle of inclination of the plane is increased, then acceleration of
the system will
A. increase
B. decrease
C. remain the same
21,The total time taken by a projectile to reach maximum height and to return back to the
ground, is known as time of flight.
A. Yes B. No
21.The range of a projectile is maximum, when the angle of projection is
A. 30° B. 45°
C. 60° D. 90
22. The mechanical advantage of a lifting machine is the ratio of
A. distance moved by effort to the distance moved by load
B. load lifted to the effort applied
C. output to the input
D. all of the above
23.Static friction is always __________ dynamic friction.
A. equal to
B. less than
C. greater than
24.A body will begin to move down an inclined plane if the angle of inclination of the plane is
__________ the angle of friction.

A. equal to
B. less than
C. greater than
25.When a particle moves along a circular path with uniform velocity, there will be no tangential
acceleration.
A. Correct B. Incorrect
26.The bodies which rebound after impact are called
A. inelastic bodies
B. elastic bodies
C. neither elastic nor inelastic bodies
D. none of these
27.The maximum frictional force, which comes into play, when a body just begins to slide over the
surface of the other body, is known as
A. static friction
B. dynamic friction
C. limiting friction
D. coefficient of friction
28.The distance, between the point of projection and the point where the projectile strikes the
ground, is known as range.
28.The algebraic sum of the resolved parts of a number of forces in a given direction is equal to the
resolved part of their resultant in the same direction. This is known as
A. principle of independence of forces
B. principle of resolution of forces
C. principle of transmissibility of forces
D. none of these
29.The triangle law of forces states that if two forces acting simultaneously on a particle, be
represented in magnitude and direction by the two sides of a triangle taken in order, then their
resultant may be represented in magnitude and direction by the third side of a triangle, taken in
opposite order.
A. True B. False
.
30.The angle between two forces when the resultant is maximum and minimum respectively are
A. 0° and 180°
B. 180° and 0°
C. 90° and 180°
D. 90° and 0°
31.The path of the projectile is a parabola.
A. True B. False
32.The equivalent length of a simple pendulum which gives the same frequency as compound
pendulum is
A.
B.
C.
D.

33.A redundant frame is also called __________ frame.
A. perfect
B. imperfect
C. deficient
34.Mass moment of inertia of a uni form thin rod of mass M and length (l) about its mid-point and
perpendicular to its length is
A.
B.
C.
D.
35.When a rigid body is suspended vertically, and it oscillates with a small amplitude under the
action of the force of gravity, the body is known as
A. simple pendulum
B. compound pendulum
C. torsional pendulum
D. second's pendulum
36.Moment of inertia of a hollow circular section, as shown in the below figure about X-axis, is
A.
B.
C.
D.
37.During elastic impact, the relative velocity of the two bodies after impact is __________ the
relative velocity of the two bodies before impact.
A. equal to
B. equal and opposite to
C. less than
D. greater than

38.One watt is equal to
A. 0.1 joule/s
B. 1 joule/s
C. 10 joules/s
D. 100 joules
39.Two like parallel forces are acting at a distance of 24 mm apart and their resultant is 20 N. It the line of
action of the resultant is 6 mm from any given force, the two forces are
A. 15 N and 5 N
B. 20 N and 5 N
C. 15 N and 15 N
D. none of these
40.The point, through which the whole weight of the body acts, irrespective of its position, is known
as
A. moment of inertia
B. centre of gravity
C. centre of percussion
D. centre of mass
41.The rate of change of momentum is directly proportional to the impressed force, and takes place in the
same direction in which the force acts. This statement is known as
A. Newton's first law of motion
B. Newton's second law of motion
C. Newton's third law of motion
D. none of these
42.The principle of transmissibility of forces states that, when a force acts upon a body, its effect is
A. same at every point on its line of action
B. different at different points on its line of action
C. minimum, if it acts at the centre of gravity of the body
D. maximum, if it acts at the centre of gravity of the body
43.The resultant of two forces P and Q acting at an angle θ is
A.
B.
C.
D.
44.
The above figure shows the three coplaner forces P, Q and R acting at a point O. If these forces are
in equilibrium, then
A.

B.
C.
D.
45.In the shown figure, the tension (T) in the string will be
A.
B.
C.
D.
46.The static friction
A. bears a constant ratio to the normal reaction between the two surfaces
B. is independent of the area of contact, between the two surfaces
C. always acts in a direction, opposite to that in which the body tends to move
D. all of the above
47.The maximum height of a projectile on a horizontal plane, is
A.
B.
C.
D.
48.The total energy possessed by a system of moving bodies
A. is constant at every instant
B. varies from point to point
C. is maximum in the start and minimum at the end
D. is minimum in the start and maximum at the end
49.The terms 'leverage' and 'mechanical advantage' Of a compound lever have got the same meaning.
50.For a self locking machine, the efficiency must be
A. equal to 50%
B. less than 50%

C. greater than 50%
D. 100%
51.The resultant of the two forces P and Q is R. If Q is doubled, the new resultant is perpendicular to P.
Then
A. P = Q
B. Q = R
C. Q = 2R
D. none of these
52.If the body falls freely under gravity, then the gravitational acceleration is taken as
A. +8.9 m/s2
B. -8.9 m/s2
C. +9.8 m/s2
D. -9.8 m/s2
53.Three forces acting on a rigid body are represented in magnitude, direction and line of action by the three
sides of a triangle taken in order. The forces are equivalent to a couple whose moment is equal to
A. area of the triangle
B. twice the area of the triangle
C. half the area of the triangle
D. none of these
54.If tension in the cable supporting a lift moving downwards is half the tension when it is moving upwards,
the acceleration of the lift is
A. g/2
B. g/3
C. g/4
D. none of these
55.The time of flight (t) of a projectile on a horizontal plane is given by
A.
B.
C.
D.
56.The law of motion involved in the recoil of gun is
A. Newton's first law of motion
B. Newton's second law of motion
C. Newton's third law of motion
D. none of these
57.The range of projectile will be maximum for a given velocity of projectile, when the angle of projection
(α) is
A. β/2
B. 30° + β/2
C. 45° + β/2
D. 60° + β/2
58.When two elastic bodies collide with each other,
A. the two bodies will momentarily come to rest after collision
B. the two bodies tend to compress and deform at the surface of contact
C. the two bodies begin to regain their original shape

D. all of the above
59.A circular hole of 50 mm diameter is cut out from a circular disc of 100 mm diameter as shown in
the below figure. The centre of gravity of the section will lie
A. in the shaded area
B. in the hole
C. at O
60.A body of mass m moving with a constant velocity v strikes another body of same mass m moving with
same velocity but in opposite direction. The common velocity of both the bodies after collision is
A. v B. 2v
C. 4v D. 8v
61.The resultant of two equal forces P making an angle θ, is given by
A. 2 P sin θ /2
B. 2 P cos θ /2
C. 2 P tan θ /2
D. 2 P cot θ /2
62.The force, by which the body is attracted, towards the centre of the earth, is called
A. impulsive force
B. mass
C. weight
D. momentum
63.Coplaner concurrent forces are those forces which
A. meet at one point, but their lines of action do not lie on the same plane
B. do not meet at one point and their lines of action do not lie on the same plane
C. meet at one point and their lines of action also lie on the same plane
D. do not meet at one point, but their lines of action lie on the same plane
64.One joule means that
A. work is done by a force of 1 N when it displaces a body through 1m
B. work is done by a force of 1 kg when it displaces a body through 1 m
C. work is done by a force of 1 dyne when it displaces a body through 1 cm
D. work is done by a force of 1 g when it displaces a body through 1 cm
65.If a pendulum is taken 1 km below the earth surface in a mine, it will __________ in time.
A. gain B. loose
65.The angle of inclination of the plane at which the body begins to move down the plane, is called
A. angle of friction
B. angle of repose
C. angle of projection
D. none of these
66.Which of the following statement is incorrect?
A. A force acting in the opposite direction to the motion of the body is called force of friction.
B. The ratio of the limiting friction to the normal reaction is called coefficient of friction.

C. A machine whose efficiency is 100% is known as an ideal machine.
D. The velocity ratio of a machine is the ratio of load lifted to the effort applied.
67.A lead ball with a certain velocity is made to strike a wall, it falls down, but rubber ball of same mass and
with same velocity strikes the same wall, it rebounds. Select the correct reason from the following:
A. both the balls undergo an equal change in momentum
B. the change in momentum suffered by rubber ball is more than the lead ball
C. the change in momentum suffered by rubber ball is less than the lead ball
D. none of the above
68.A ladder is resting on a rough ground and leaning against a smooth vertical wall. The force of friction will
act
A. downward at its upper end
B. upward at its upper end
C. zero at its upper end
D. perpendicular to the wall at its upper end
69.The three forces of 100 N, 200 N and 300 N have their lines of action parallel to each other but act in the
opposite directions. These forces are known as
A. coplaner concurrent forces
B. coplaner non-concurrent forces
C. like parallel forces
D. unlike parallel forces
70.The slope on the road surface generally provided on the curves is known as
A. angle of friction
B. angle of repose
C. angle of banking
D. none of these
71.The force applied on a body of mass 100 kg to produce an acceleration of 5 m/s2
, is
A. 20N
B. 100N
C. 500N
D. none of these
72.Which of the following statement is correct?
A. The algebraic sum of the forces, constituting the couple is zero.
B. The algebraic sum of the forces, constituting the couple, about any point is the same.
C. A couple cannot be balanced by a single force but can be balanced only by a couple of opposite sense.
D. all of the above
1. (Ans: b) 21.(Ans: a) 41.(Ans: a) 61.(Ans: b)
2. (Ans: b) 22.(Ans: b) 42.(Ans: b) 62.(Ans: c)
3. (Ans: a) 23.(Ans: b) 43.(Ans: b) 63.(Ans: c)
4. (Ans: a) 24.(Ans: c) 44.(Ans: c) 64.(Ans: a)
5. (Ans: b) 25.(Ans: c) 45.(Ans: b) 65.(Ans: a)
6. (Ans: b) 26.(Ans: a) 46.(Ans: b) 66.(Ans: d)
7. (Ans: c) 27.(Ans: b) 47.(Ans: b) 67.(Ans: b)
8. (Ans: d) 28.(Ans: c) 48.(Ans: d) 68.(Ans: d)
9. (Ans: b) 29.(Ans: a) 49.(Ans: a) 69.(Ans: d)
10. (Ans: a) 30.(Ans: b) 50.(Ans: a) 70.(Ans: c)
11. (Ans: c) 31.(Ans: a) 51.(Ans: b) 71.(Ans: c)
12. (Ans: b) 32.(Ans: a) 52.(Ans: b) 72.(Ans: d)

13. (Ans: d) 33.(Ans: a) 53.(Ans: c)
14. (Ans: d) 34.(Ans:b) 54.(Ans: b)
15. (Ans: b) 35.(Ans: b) 55.(Ans: d)
16. (Ans: d) 36.(Ans: d) 56.(Ans: c)
17. (Ans: b) 37.(Ans: b) 57.(Ans: c)
18. (Ans: c) 38.(Ans: d) 58.(Ans: d)
19. (Ans: a) 39.(Ans: b) 59.(Ans: a)
20. (Ans: b) 40.(Ans: b) 60.(Ans: b)

THERMAL ENGINEERING
1. Thermodynamics is the science of
(a) Earth
(b) Energy
(c) Temperature
(d) Environment
2. The cyclic integral of any thermodynamic property is
(a) 1
(b) -1
(c) 0
(d) ∞
3. Statistical thermodynamics is following ________________ approach
(a) Zeroth law
(b) Macroscopic
(c) First law
(d) Microscopic
4. The relation between Cp, Cv and R is given by the relation
(a) Cp-Cv = R
(b) Cp+Cv = R
(c) Cp/Cv = R
(d) Cp+Cv = R-1
5. If the heat transfer in a process is zero, then it is called as
(a) Isothermal process
(b) Polytrophic process
(c) Adiabatic process
(d) Isobaric process
6. The work done in __________ process is zero.
(a) isothermal
(b) Polytrophic
(c) Isochoric
(d) Isobaric
7. The First law of thermodynamics is given by the formula
(a) Q = W-ΔU
(b) Q = W+ΔU
(c) Q = W+ΔS
(d) Q = W-ΔS

8. Both __________________________ constitute universe
(a) Temperature & heat
(b) System & surrounding
(c) Heat & work
(d) Enthalpy & entropy
9. in an open system_____________________ will cross the boundary
(a) Mass alone
(b) Energy alone
(c) Both mass and energy
(d) Nothing
10. In a closed system_______________________ will cross the boundary
(a) Mass alone
(b) Energy alone
(d) Nothing
11. Which one of the following is the path function?
(a) Heat
(b) Temperature
(c) Pressure
(d) Volume
12. Which one of the following is the point function?
(a) Heat
(b) Work
(c) Temperature
(d) None of the above
13. In an isolated system_______________________ will cross the boundary
(a) Mass alone
(b) Energy alone
(d) Nothing
14. Intensive property is independent of the _______________of the system.
(a) Weight
(b) Mass
(c) Gravity
(d) Inertia
15. Extensive property is dependent on the _______________of the system.
(a) Weight

(b) Mass
(c) Gravity
(d) Inertia
16. The system is free from any unbalanced forces then it is said to be in a state of
(a) Closed system
(b) Isolated system
(c) Quasi-static
(d) Mechanical equilibrium
17. If there is no temperature change within the system then it is said to be in a state of
(a) Closed system
(b) Isolated system
(c) Thermal equilibrium
18. If the initial and end state of a process is same then it is known as
(a) State
(b) Process
(c) Cycle
(d) Property
19. When temperature is constant through out the process then it is known as
(a) Isobaric
(b) Isothermal
(c) Adiabatic
(d) Isentropic
20. When entropy is constant through out the process then it is known as
(a) Isobaric
(b) Isothermal
(c) Isochoric
(d) Isentropic
21. When pressure is constant through out the process then it is known as
(a) Isobaric
(b) Isothermal
(c) Polytrophic
(d) Isentropic
22. When volume is constant through out the process then it is known as
(a) Isobaric
(b) Isochoric
(c) Adiabatic

(d) Polytrophic
23. When a system existing in single phase only then it is known as
(a) Open system
(b) Homogeneous system
(c) Heterogeneous system
(d) Isolated system
24. When a system existing in more than one phase then it is known as
(a) Open system
(d) Isolated system
25. Enthalpy is equal to
(a) u+pv
(b) v+pu
(c) p+pu
(d) p+pv
26. A device which is used to increase the velocity and decrease the pressure is known as
(a) compressor
(b) blower
(c) nozzle
(d) diffuser
27. A device which is used to increase the pressure and decrease the velocity is known as
(a) compressor
(b) Blower
(c) Nozzle
(d) Diffuser
28. The work done in free expansion process is
(a) Zero
(b) less than zero
(c) Greater than zero
(d) Unpredictable
29. Characteristic gas constant is equal to
(a) Ru.M
(a) Earth
(b) Energy
(c) Temperature

(d) Environment
(a) 2
(b) -2
(c) 1
(d) ∞
(a) Zeroth law
(b) Macroscopic
(c) First law
(d) Microscopic
(a) Cp-Cv = R
(b) Cp+Cv = R
(c) Cp/Cv = R
(d) Cp+Cv = R-2
(a) isothermal
(b) Polytrophic
(c) Isochoric
(d) Isobaric
(a) Q = W-ΔU
(b) Q = W+ΔU
(c) Q = W+ΔS
(d) Q = W-ΔS
(c) Heat & work

(a) Mass alone
(b) Energy alone
(d) Nothing
(a) Mass alone
(b) Energy alone
(d) Nothing
(a) Heat
(b) Temperature
(c) Pressure
(d) Volume
(a) Heat
(b) Work
(c) Temperature
(a) Mass alone
(b) Energy alone
(d) Nothing
(a) Weight
(b) Mass
(c) Gravity
(d) Inertia
(a) Weight
(b) Mass
(c) Gravity
(d) Inertia

(a) Closed system
(b) Isolated system
(c) Quasi-static
(a) Closed system
(b) Isolated system
(a) State
(b) Process
(c) Cycle
(d) Property
(a) Isobaric
(b) Isothermal
(c) Adiabatic
(d) Isentropic
(a) Isobaric
(b) Isothermal
(c) Isochoric
(d) Isentropic
(a) Isobaric
(b) Isothermal
(c) Polytrophic
(d) Isentropic
22. When volume is constant through out the process then it is known as
(a) Isobaric
(b) Isochoric
(c) Adiabatic
(d) Polytrophic
23. When a system existing in single phase only then it is known as
(a) Open system

(d) Isolated system
24. When a system existing in more than one phase then it is known as
(a) Open system
(d) Isolated system
25. Enthalpy is equal to
(a) u+pv
(b) v+pu
(c) p+pu
(d) p+pv
26. A device which is used to increase the velocity and decrease the pressure is known as
(a) compressor
(b) blower
(c) nozzle
(d) diffuser
27. A device which is used to increase the pressure and decrease the velocity is known as
(a) compressor
(b) Blower
(c) Nozzle
(d) Diffuser
28. The work done in free expansion process is
(a) Zero
(b) less than zero
(c) Greater than zero
(d) Unpredictable
29. Characteristic gas constant is equal to
(a) Ru.M
(a) Earth
(b) Energy
(c) Temperature
(d) Environment
(a) 2
(b) -2

(c) 1
(d) ∞
(a) Zeroth law
(b) Macroscopic
(c) First law
(d) Microscopic
(a) Cp-Cv = R
(b) Cp+Cv = R
(c) Cp/Cv = R
(d) Cp+Cv = R-2
(a) isothermal
(b) Polytrophic
(c) Isochoric
(d) Isobaric
(a) Q = W-ΔU
(b) Q = W+ΔU
(c) Q = W+ΔS
(d) Q = W-ΔS
(c) Heat & work
(a) Mass alone
(b) Energy alone
(d) Nothing

(a) Mass alone
(b) Energy alone
(d) Nothing
(a) Heat
(b) Temperature
(c) Pressure
(d) Volume
(a) Heat
(b) Work
(c) Temperature
(a) Mass alone
(b) Energy alone
(d) Nothing
(a) Weight
(b) Mass
(c) Gravity
(d) Inertia
(a) Weight
(b) Mass
(c) Gravity
(d) Inertia
(a) Closed system
(b) Isolated system
(c) Quasi-static

(a) Closed system
(b) Isolated system
(a) State
(b) Process
(c) Cycle
(d) Property
(a) Isobaric
(b) Isothermal
(c) Adiabatic
(d) Isentropic
(a) Isobaric
(b) Isothermal
(c) Isochoric
(d) Isentropic
(a) Isobaric
(b) Isothermal
(c) Polytrophic
(d) Isentropic
50.A system undergoing reversible process has _________ efficiency
(a) minimum
(b) maximum
(c) zero
(d) none of the above
51. The isentropic law is given by
(a) pv = constant
(b) pvγ = constant
(c) pvn = constant
(d) p/T = constant
52. The energy required to raise the temperature of the unit mass of a substance by one degree at constant
Volume is known as

(a) super heat
(b) specific heat at constant volume
(c) Degree of heat
(d) Specific heat at constant pressure
53. The energy required to raise the temperature of the unit mass of a substance by one degree at constant
Pressure is known as
(a) Super heat
(b) Specific heat at constant volume
(c) Degree of heat
(d) Specific heat at constant pressure
54. The fluid pressure is reduced from higher pressure to lower pressure at constant enthalpy then it is
(a) Isentropic process
(b) Throttling process
(c) Isobaric process
(d) Adiabatic process
55. The ratio of specific heat (γ) for air is approximately equal to
(a) 1.0
(b) 0.287
(c) 1.4
(d) 2.5
56. Which one of the following is intensive property?
(a) Temperature
(b) Volume
(c) Density
57. A device which develops work continuously without the expenditure of heat energy is called as
(a) Air compressor
(b) Turbine
(c) PMM-I
(d) Diffuser
58. Which one of the following is extensive property?
(a) Temperature
(b) Volume
(c) Pressure
(d) Viscosity
59. Classical thermodynamics is following ________________ approach
(a) Zeroth law
(b) Macroscopic

(c) First law
(d) Microscopic
60. Air compressor is an example for
(a) Open system
(b) Closed system
(c) Isolated system
61. V α T at constant pressure, is known as
(a) Dalton’s law
(b) Boyle’s law
(c) Charle’s law
(d) Amagat’s law
62. V α 1/P at constant temperature, is known as
(a) Boyle’s law
(b) Dalton’s law
(c) Amagat’s law
(d) Charle’s law
63. The gases which obey Boyle’s law, Charle’s law and Gay Lussac’s law are known as
(a) Real gases
(b) Ideal gases
(c) Inert gases
64. Carnot engine is
(a) irreversible engine
(b) possible engine
(c) ideal imaginary engine
65. The efficiency of Carnot cycle with T1 = 1000 K and T2 = 100 K is approximately
(a) 10 %
(b) 50 %
(c) 90 %
(d) 0 %
66. The efficiency of a heat engine is equal to
(a) Work output X Heat input
(b) Work output / Heat input
(c) Heat input + Work output
(d) Heat input – Work output

67. The efficiency of an actual engine is
(a) less than carnot engine
(b) greater than carnot engine
(c) equal to carnot engine
68. It is impossible to construct an engine which produces work output by exchanging heat between a singl
reservoir
(a) Carnot theorm
(b) Kelvin-plank statement
(c) Clausius statement
(d) Clausius inequality
69. Entropy is a
(a) positive function
(b) negative function
(c) point function
(d) path function
70. PMM – II violates
(a) Clausius statement
(b) Carnot theorem
(c) Clausius inequality
(d) Kelvin Planck statement
71. The unit of entropy is
(a) J.K
(b) J/K
(c) J
72. Entropy principle states that the entropy of an isolated system
(a) never decrease
(b) never increase
(c) remains constant
(d) always equal to zero
73.Which one of the following is considered as low grade energy?
(a) Mechanical work
(b) Electrical energy
(c) Heat energy
(d) Wind energy

74.The combined equation for first and second law of thermodynamics is
(a) T.dQ = p.dv + Δu
(b) T.ds = p.dv + Δu
(c) p.ds = v.dT + Δu
(d) p.dQ = v.dT + Δu
75.It is impossible to reduce any system to absolute zero temperature in a finite number of operations
(a) Zeroth law of thermodynamics
(b) First law of thermodynamics
(c) Second law of thermodynamics
(d) Third law of thermodynamics
1. (Ans: b) 21.(Ans: a) 41.(Ans: a) 61.(Ans: c)
2. (Ans: c) 22.(Ans: b) 42.(Ans: b) 62.(Ans: a)
3. (Ans: d) 23.(Ans: b) 43.(Ans: b) 63.(Ans: b)
4. (Ans: a) 24.(Ans: c) 44.(Ans: a) 64.(Ans: c)
5. (Ans: c) 25.(Ans: a) 45.(Ans: c) 65.(Ans: c)
6. (Ans: c) 26.(Ans: c) 46.(Ans: b) 66.(Ans: b)
7. (Ans: b) 27.(Ans: d) 47.(Ans: b) 67.(Ans: a)
8. (Ans: b) 28.(Ans: a) 48.(Ans: a) 68.(Ans: b)
9. (Ans: c) 29.(Ans: b) 49.(Ans: c) 69.(Ans: c)
10. (Ans: b) 30.(Ans: d) 50.(Ans: b) 70.(Ans: d)
11. (Ans: a) 31.(Ans: a) 51.(Ans: b) 71.(Ans: b)
12. (Ans: c) 32.(Ans: c) 52.(Ans: b) 72.(Ans: a)
13. (Ans: d) 33.(Ans: c) 53.(Ans: d) 73.(Ans: c)
14. (Ans: b) 34.(Ans:c) 54.(Ans: b) 74.(Ans: b)
15. (Ans: b) 35.(Ans: b) 55.(Ans: c) 75.(Ans: d)
16. (Ans: d) 36.(Ans: c) 56.(Ans: a)
17. (Ans: c) 37.(Ans: c) 57.(Ans: c)
18. (Ans: c) 38.(Ans: d) 58.(Ans: b)
19. (Ans: b) 39.(Ans: b) 59.(Ans: b)
20. (Ans: d) 40.(Ans: c) 60.(Ans: a)

AUTOMOBILE ENGINEERING
1. The condition that causes vapour locking in a brake system is
A. overheating of the fluid due to frequent brake application
B. overcooling of the brakes during high speed driving
C. keeping the vehicle without use for an extended period
D. an excessively high engine speed on a downhill road
2. The portion of a crankshaft which rests on cylinder block is called main journal.
A. Yes B. No
3. The motion of the cam is transferred to the valves through
A. pistons
B. rocker arms
C. camshaft pulley
D. valve stems
4.Which of the following symptom is caused as a result of brake disc run out ?
A. Ineffectiveness of the brakes
B. Judder during braking
C. Localized wearing of the brake pads
D. Rapid wearing of the brake pads
5. If the engine coolant leaks into the engine oil, then engine oil
A. appears milky
B. becomes foamy
C. turns black
D. none of these
6.The function of an alternator in an automobile is to
A. supply electric power
B. convert mechanical energy into electrical energy
C. continually recharge the battery
D. partly convert engine power into electric power

7.A clutch is usually designed to transmit maximum torque which is
A. equal to the maximum engine torque
B. 80 per cent of the maximum engine torque
C. 150 per cent of the maximum engine torque
D. none of these
8. What type of bearing is used for main bearings and connecting rod bearings ?
A. Ballbearings
B. Plain bearings
C. Needle roller bearing
D. Taper roller bearing
9. It is necessary to maintain the valve clearances as they
A. reduce the resistance to sliding that occurs between the cam and the tappet
B. allow for lengthening of the valves owing to the heat of combustion
C. increase the speed at which the valves move up and down
D. make the crankshaft turn smoothly
10.The torque available at the contact between driving wheels and road is known as
A. brake effort
B. tractive effort
C. clutch effort
D. none of these
11.A traction control system (TCS) in automobiles controls the
A. vibrations on the steering wheel
B. engine power during acceleration
C. torque that is transmitted by the tyres to the road surface
D. stopping distance in case of emergency
12.In radial tyres
A. one ply layer runs diagonally one way and another layer runs diagonally the other way
B. all plies run parallel to one another and vertical to tyre bead

C. inner tubes are always used
D. none of these
13.The oil pump is driven by the
A. camshaft
B. alternator shaft
C. crankshaft via drive belt
D. crankshaft directly
14.The vehicle ride will be comfortable if
A. unsprung mass is kept minimum
B. sprang mass is kept minimum
C. vehicle mass is kept minimum
D. all of these
15.The main function of intake manifold is that it
A. promotes the mixture of air and fuel
B. reduces intake noise
C. cools the intake air to a suitable temperature
D. distributes intake air equally to the cylinders
16.In automobiles G.V.W. refers to
A. gross vehicle width
B. gross vehicle weight
C. gross vehicle wheel base
D. gross vehicle wheel traction
17.The firing order for an in-line four cylinder I.C. engine is
A. 1-2-3-4 B. 1-3-4-2
C. 1-2-4-3 D. 1-3-2-4
18.In a ventilated disc brake,
A. a duct directs air towards the caliper for cooling while the vehicle is moving

B. caliper is covered with cooling fins
C. disc contains many small holes for optimum cooling performance
D. disc contains radial vanes between its rubbing surfaces for optimum cooling performance
19.The effect of having excess camber is
A. excessive steering alignment torque
B. hard steering
C. too much traction
D. uneven tyre wear
20.If the air-fuel mixture in a spark ignition engine is too rich, then air-fuel ratio is about
A. 17:1 B. 15:1
C. 13:1 D. 10:1
21.The co-efficient of rolling resistance for a truck weighing 63 500 N is 0.018. The rolling resistance to the truck is
A. 1.143 N
B. 11.43 N
C. 114.3 N
D. 1143 N
22.If the air-fuel mixture ignites before the spark takes place at spark plug, the condition is called
A. detonation B. ignition
C. pre-ignition D. rumble
23.The information provided by the oxygen (O2) sensor to the feedback control system is about the
A. air-fuel ratio
B. air temperature
C. air flow speed
D. exhaust gas volume
24.The difference between DOT 3 and DOT 4 brake fluids is
A. DOT 4 fluid has a higher boiling point than DOT 3 fluid
B. DOT 4 fluid has a lower boiling point than DOT 3 fluid

C. DOT 3 and DOT 4 fluids have the same boiling point, but DOT 4 fluid has a longer service life
D. DOT 4 fluid is more resistant to freezing than DOT 3 fluid
25.The battery is an electrochemical device, which means battery
A. makes chemicals by mechanical means
B. uses chemical action to provide electricity
C. has curved plates instead of flat plates
D. does not use an electrolyte
24.The operation of removing trapped air from the hydraulic braking system is known as
A. trapping B. tapping
C. bleeding D. cleaning
25.The aluminium alloy is used in cylinder blocks because
A. it is lighter and have good heat dissipation characteristics
B. material cost is low
C. it does not require any cylinder liners
D. the piston is also made of aluminium alloy
26.The tilting of the front wheels away from the vertical, when viewed from the front of the car, is called
A. camber B. caster
C. toe-in D. toe-out
27.The main function of the tread pattern on tyre is that
A. the tread grooves pass air between the tyre and road surface, thereby preventing tyre from overheating
B. the crests between the tread grooves absorb road noise
C. in wet conditions, the tread grooves expel water that is drawn between the tyre and road surface
D. the tread pattern protects the tyre's inner carcass from small stones and pieces of glass
28.The compression ratio in petrol engine is kept less than in Diesel engine because
A. it makes petrol engines lighter
B. higher or equivalent compression ratio in petrol engines is not possible due to pre-ignition

C. less compression ratio gives better performance
D. it is just customary to have less compression ratio in petrol engines
29.The petrol engines are also known as
A. spark ignition (S.I.) engines
B. compression ignition (C.I.) engines
C. steam engines
D. none of these
30.Which of the following indicates a multigrade oil ?
A. SAE 30
B. API SF
C. SAE 20 W-50
D. API 5
31.The painting of automobiles is done to
A. prevent rust from growing on the body
B. improve its external appearance
C. retain the characteristics of steel for long
D. all of these
32.The main task of a battery in automobiles is to
A. supply electricity to the alternator
B. act as a reservoir or stabilizer of electricity
C. supply electricity to the vehicle's electrical system at all times while the engine is running
D. supply a large amount of power to turn the starter motor when the engine is being started
33.The major purpose of an electronically-controlled automatic transmission is that this type of transmission
A. eliminates gear clutches
B. eliminates the gear shift lever
C. reduces the number of automatic-transmission components
D. reduces shift shock and achieves more efficient transmission of engine torque

34.The connecting rods are generally made of __________ shaped cross-section.
A. I B. C
C. L D. H
35.The air resistance to a car at 20 kmph is R. The air resistance at 40 kmph will be
A. R
B. 2 R
C. 4R
D. 4 R
36.The size of engine cylinder is referred in terms of its
A. diameter and bore
B. displacement and efficiency
C. bore and stroke
D. bore and length
37.The purpose of a cylinder head gasket is to
A. prevent the combustion gases from leaking from the joint between the cylinder block and the cylinder head
B. prevent engine oil from going into combustion chamber
C. removes impurities from cylinder head lubricating oil
38.The function of antilock brake system (ABS) is that is
A. reduces the stopping distance
B. minimises the brake fade
C. maintains directional control during braking by preventing the wheels from locking
D. prevents nose dives during braking and thereby postpones locking of the wheel
39.A worm gear is used as the pinion for the rack and pinion type of steering gearbox, because it
A. improves steering comfort when steering wheel is turned to effect small changes in the direction of forward mo
B. allows the steering wheel to be turned by a greater amount when steering
C. makes the steering more responsive

D. reduces the amount of kick-back for large steering angles
40.The octane rating of petrol commerically available is
A. 85-95 B. 95-100
C. 100-110 D. 110-125
41.The stroke of an engine is the
A. volume of the cylinder
B. length of the connecting rod
C. internal diameter of the cylinder
D. distance between T.D.C. and B.D.C.
42.The characteristic that is enhanced by the use of cylinder sleeves is
A. cooling efficiency
B. resistance to wear
C. lubrication performance
D. none of these
43.The rating of C.I. engine fuel (Diesel) is given by
A. octane number
B. performance number
C. cetane number
D. none of these
44.Which part of the automobile tyre is subjected to greatest flexing action ?
A. Bead
B. Side wall
C. Shoulder
D. Tread
45.The temperature at which tyre inflation pressure should be checked is
A. 20°C
B. 25°C

C. 35°C
D. ambient temperature
46.The calorific value of Diesel is about
A. 36.5 MJ/kg
B. 38.5 MJ/kg
C. 42.5 MJ/kg
D. 45.5 MJ/kg
47.The negative plates of a lead acid battery has
A. lead peroxide (PbO2)
B. spongy lead (Pb)
C. lead sulphate (PbSO4)
D. sulphuric acid (H2SO4)
48.The function of oil-control rings is that it
A. lubricates the cylinder wall by releasing oil from its hole
B. keeps the cylinder wall lubricated by holding oil in its channel
C.
prevents engine oil from going into the combustion chamber and returns excess lubricating oil off the cylinder wall
return holes in the piston to the oil pan
D. maintains a seal and prevents escape of burned gases and oil leakage
49.The starter motor is driven by
A. chain drive
B. gear drive
C. flat belt drive
D. V-belt drive
50.The octane number of compressed natural gas (CNG) is
A. 90 B. 100
C. 110 D. 120
51.The compression ratio for Diesel engines usually lies in the range of
A. 6-10 B. 10-15

C. 15-25 D. 25-40
52.In a petrol engine, the high voltage for spark plug is in the order of
A. 1000 volts
B. 2000 volts
C. 11 kilovolts
D. 22 kilovolts
53.The service brakes employed in cars are generally operated
A. mechanically
B. hydraulically
C. pneumatically
D. none of thes
54.The boiling point of Diesel fuel is in the range of
A. 70°C to 100°C
B. 100°C to 120°C
C. 120°C to 180°C
D. 180°C to 360 °C
55.During braking, the brake shoe is moved outward to force the lining against the
A. wheel piston or cylinder
B. anchor pin
C. brake drum
D. wheel rim or axle
56.The purpose of transmission in an automobile is
A. to vary the speed of automobile
B. to vary the torque at the wheels
C. to vary the power of automobile
D. none of these
57.When indicated power (I.P.) and frictional power (F.P.) are known, we can calculate

A. brake power
B. compression ratio
C. specific air consumption
D. mean effective pressure
58.The best fuels for compression ignition engines are
A. straight chain paraffins
B. aromatics
C. branched chain paraffins
D. napthalenes
59.Damper is also known as
A. shock absorber
B. torsion bar
C. spring
D. radius rod
60.The main characteristics of a maintenance-free (MF) battery is that
A.
a maintenance-free battery requires little maintenance during normal use and it is sufficient to add water instead of an elec
sulphuric acid
B. a maintenance-free battery has a relatively short shelf life when compared with standard batteries
C.
since it is sealed, the water in a maintenance-free battery is not lost through evaporation thus accordingly it is not n
up the cells with water
D. recharging of a maintenance-free battery is neither required nor possible
61.The most accurate ignition system of a spark ignition engine is
A. magneto system
B. battery system
C. electronic control unit system
D. magneto and electronic system
62.The main function of a resonator is that it
A. regulates the intake air flow rate

B. reduces the intake air noise .
C. enhances intake efficiency
D. regulates the intake air temperature
63.For the same maximum pressure and temperature
A. Diesel cycle is more efficient than Otto cycle
B. Otto cycle is more efficient than Diesel cycle
C. both Otto cycle and Diesel cycle are equally efficient
64.In which of the following conditions, the idle CO percentage should be measured with the vehicle ?
A. Headlights and other electrical devices are switched off.
B. Headlights and other electrical devices are switched on.
C. Headlights and other lights are switched off.
D. Headlights are switched on
65.The mechanical efficiency (ηm) of an I.C. engine is equal to (where I.P. = Indicated power,B.P. = Brake power and F.P. = Frict
A. I.P/B.P. B. B.P/I.P.
C. B.P/F.P D. F.P./B.P
66.The lower cylindrical portion of the piston which improves piston cooling performance is called
A. piston crown
B. connecting rod
C. piston pin boss
D. piston skirt
67.The most effective method of controlling S.I. engine exhaust emission is by
A. recirculating exhaust
B. using catalytic converter
C. using some additives in the fuel
D. none of these
68.The power actually developed inside the engine cylinder is called as
A. indicated power

B. brake power
C. frictional power
D. none of these
69.If clearance volume of I.C. engines is increased, the compression ratio will
A. increase
B. decrease
C. remain constant
D. be doubled
70.The basic function of the suspension is to
A. absorb vibration and impact forces from the road surface
B. ensure that the steering wheel can deliver a suitable amount of steering force
C. ensure that wheel alignment is not disturbed during driving
D. automatically correct the effects of over steering
71.The combustion process in a Diesel engine is a
A. constant volume process
B. constant pressure process
C. constant temperature process
D. adiabatic process
72.The compression ratio of a petrol engine is nearly
A. 4:1 B. 8:1
C. 15:1 D. 20:1
73.During suction stroke, the inside pressure of cylinder is
A. more than the atmospheric pressure
B. less than the atmospheric pressure
C. equal to the atmospheric pressure
D. none of these
74.The condition that results in large quantities of CO emission is

A. insufficient air during combustion
B. insufficient fuel during combustion
C. low temperature combustion
D. high temperature combustion
75.Vulcanizing means
A. heating rubber under pressure
B. spraying with special paint
C. melting rubber while stirring it
D. none of these
76.When a gear box has four forward speeds and one reverse speed, it is said to be a
A. 3-speed gear box
B. 4-speed gear box
C. 5-speed gear box
D. 6-speed gear box
77.The brake pedal during ABS operation
A. is pushed upward forcefully
B. pedal stroke becomes longer
C. transmits slight kickback to the driver's foot
D. all of the above
78.In a four stroke engine for each crankshaft revolution, the camshaft revolves
A. one-half turn
B. one turn
C. two turns
D. four turn

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