SSC JE PREVIOUS YEAR QUESTION SET 2

1 - An ideal air compressor cycle (with clearance) on p-v diagram can be represented by ________ processes.

1) one adiabatic, two isobaric, and one constant volume
2) two adiabatic and two isobaric
3) two adiabatic, one isobaric, and one constant volume
4) one adiabatic, one isobaric, and two constant volume

... Answer is
two adiabatic and two isobaric

2- In a shell and tube heat exchanger, baffles are provided on the shell side to ______.

1) Prevent the stagnation of shell side fluid
2) Improve heat transfer
3) Provide support for tubes
4) All options are correct

... Answer is
All options are correct

3- The ratio of the thickness of thermal boundary layer to the thickness of hydrodynamic boundary layer is equal to (Prandtl number)n, where n is______.

1) - 1/3
2) - 2/3
3) 1
4) – 1

... Answer is
- 1/3

4 - In regarding nucleate boiling _______.

1) The temperature of the surface is greater than the saturation temperature of the liquid
2) Bubbles are created by expansion of entrapped gas or vapour at small cavities in the surface
3) The temperature is greater than that of film boiling
4) All options are correct

... Answer is
The temperature is greater than that of film boiling

5 - Boundary layer is defined as ______.

1) A thin layer at the surface where gradients of both velocity and temperature are small
2) A thin layer at the surface where velocity and velocity gradients are large
3) A thick layer at the surface where velocity and temperature gradients are large
4) A thin layer at the surface where gradients of both velocity and temperature are large

... Answer is
A thin layer at the surface where gradients of both velocity and temperature are large

6 - Two insulating materials of thermal conductivity K and 2K are available for lagging a pipe carrying a hot fluid. If the radial thickness of each material is the same _____.

1) Material with higher thermal conductivity should be used for the inner layer and one with layer and one with lower thermal conductivity for the outer
2) Material with lower thermal conductivity should be used for the inner layer and one with higher thermal conductivity for the outer
3) It is immaterial in which sequence the insulating materials are used
4) None of these

... Answer is
Material with lower thermal conductivity should be used for the inner layer and one with higher thermal conductivity for the outer

7 - Critical thickness of insulation for spheres is given by _____.

1) k/h
2) k/4h
3) h/2k
4) 2k/h

... Answer is
2k/h

8 - Which surface will have the least emissivity ?

1) Smooth glass
2) Plaster
3) Aluminium foil
4) Concrete

... Answer is
Aluminium foil

9 - The process of heat transfer from one particle of the body to another without the actual motion of the particle, is known as ______.

1) Conduction
2) Convection
3) Radiation
4) All options are correct

... Answer is
Conduction

10 - The process of heat transfer from a hot body to a cold body in a straight line, without affecting the intervening medium, is known as ______.

1) Conduction
2) Convection
3) Radiation
4) All options are correct

... Answer is
Radiation

11 - Heat is transferred from an electric bulb by ______.

1) Conduction
2) Convection
3) Radiation
4) All options are correct

... Answer is
Radiation

12 - Assumption made in the Fourier's law is that the heat flow A. Is in steady state B. Through a solid medium in one dimension

1) Only (A)
2) Both (A) and (B)
3) Only (B)
4) None of these

... Answer is
Both (A) and (B)

13 - If thermal conductivity of a material of wall varies as K_0 (1 + αt), then the temperature at the centre of the wall as compared to that in case of constant thermal conductivity, will be ______.

1) More
2) Less
3) same
4) Depend on other factors

... Answer is
More

14 - With increase in temperature, thermal conductivity of air ______.

1) Increases
2) Decreases
3) Remains the same
4) None of these

... Answer is
Increases

15 - Liquid metal having highest thermal conductivity is of _______.

1) Sodium
2) Potassium
3) Lead
4) Mercury distributed

... Answer is
Sodium

16 - Minimum thermal diffusivity is of ______.

1) Aluminium
2) Rubber
3) Iron
4) Lead

... Answer is
Rubber

17 - Critical radius of a hollow cylinder is defined as _______.

1) Outer radius which gives maximum heat flow
2) Outer radius which gives minimum heat flow
3) Inner radius which gives minimum heat flow
4) Inner radius which gives maximum heat flow

... Answer is
Outer radius which gives maximum heat flow

18 - Heat exchangers are used in – A. Condensers and boilers in steam plants B. Radiators C. Intercoolers and preheaters D. Condensers and evaporators in refrigerators and air conditioners

1) Only A
2) Only B
3) Only C
4) A, B, C and D

... Answer is
A, B, C and D

19 - Automobile radiator is a heat exchanger of _____ type.

1) Counter flow
2) Parallel flow
3) Cross flow
4) Regenerator

... Answer is
Cross flow

20 - For a closed system, difference between the heat added to the system and work done by the gas, is equal to the change in_____.

1) Enthalpy
2) Entropy
3) Internal energy
4) Temperature

... Answer is
Internal energy

21 - The sequence of process that eventually returns the working substance to its original state, is known as ______.

1) Event
2) Thermodynamic cycle
3) Thermodynamic property
4) None of these

... Answer is
Thermodynamic cycle

22 - According to Kelvin-Plank's statement, a perpetual motion machine of _______.

1) First kind is possible
2) First kind is impossible
3) Second kind is impossible
4) Second kind is possible

... Answer is
Second kind is impossible

23 - According to kinetic theory of gases, at absolute zero ______.

1) Specific heat of molecules reduces to zero
2) Kinetic energy of molecules reduces to zero
3) Volume of gas reduce to zero
4) Pressure of gas reduce to zero

... Answer is
Kinetic energy of molecules reduces to zero

24 - According to Gay-Lussac's law for perfect gases, the absolute pressure of given mass varies directly as _______.

1) Temperature
2) Absolute temperature
3) Absolute temperature, if volume remains constant
4) Product of absolute temperature and volume

... Answer is
Absolute temperature, if volume remains constant

25 - Three states of matter are distinguished with respect to molecules by the ______.

1) Atoms in molecules
2) Number
3) Orientation
4) Character of motion

... Answer is
Character of motion

26 - Equal volume of all gases, at the same temperature and pressure, contain equal number of molecules. This is according to _______.

1) Charle's law
2) Avagardo's law
3) Joule's law
4) Gay Lussac law

... Answer is
Avagardo's law

27 - Specific heat of a gas, Cp = Cv, at

1) Absolute zero
2) Critical temperature
3) Triple point
4) All temperatures

... Answer is
Absolute zero

28 - The specific heat at constant volume of solids obeys Debye's T3 law at ______.

1) High temperatures
2) Low temperatures
3) High pressures
4) All temperatures

... Answer is
All temperatures

29 - A reversible process _____.

1) Must pass through a continuous series of equilibrium states
2) Leaves no history of the events in surroundings
3) Must pass through the same states on the reversed path as on the forward path
4) All options are correct

... Answer is
All options are correct

30 - In Red Wood Viscometer ______.

1) Absolute value of viscosity is determined
2) Part of the head of fluid is utilised in overcoming friction
3) Fluid discharges through orifice with negligible velocity
4) Comparison of viscosity is done

... Answer is
Absolute value of viscosity is determined

31 - A rotameter is a device used to measure ______.

1) Velocity of fluid in pipes
2) Velocity of gauges
3) Votex flow
4) Flow of fluids

... Answer is
Flow of fluids

32 - Steady flow occurs when ______.

1) Pressure does not change along the flow 2) 3) 4)
2) Velocity does not change
3) Conditions change gradually with time
4) Conditions do not change with time at any point

... Answer is
Conditions do not change with time at any point

33 - If the particles of a fluid attain such velocities that vary from point to point in magnitude and direction as well as from instant, the flow is _______.

1) Uniform flow
2) Steady flow
3) Turbulent flow
4) Laminar flow

... Answer is
Turbulent flow

34 - The combustion in a compression ignition engine is ________.

1) Steady
2) Unsteady
3) Laminar
4) Vortex

... Answer is
Unsteady

35 - For measuring flow by a Venturimeter, it should be installed in _______.

1) Vertical line
2) Horizontal line
3) Inclined line with upward flow
4) In any direction and in any location

... Answer is
In any direction and in any location

36 - A streamline is defined as the line ______.

1) Parallel to central axis flow
2) Parallel to outer surface to pipe
3) Of equal velocity in a flow
4) Along with the pressure drop is uniform

... Answer is
Of equal velocity in a flow

37 - The purpose of surge tank in a pipe line is to _______.

1) Smoothen the flow of water
2) Compensate friction losses in pipe
3) Prevent occurrence of hydraulic jump
4) Relieve pressure due to water hammer

... Answer is
Compensate friction losses in pipe

38 - The resultant upward pressure of a fluid on a floating body is equal to the weight of fluid displaced by the body. This definition is according to _______.

1) Buoyancy
2) Equilibrium of a floating body
3) Archimedes' principle
4) Bernoulli's theorem

... Answer is
Buoyancy

39 - A balloon lifting in air follows the ______.

1) Law of gravitation
2) Archimedes principle
3) Principle of buoyancy
4) All options are correct

... Answer is
All options are correct

40 - Hydraulic grade line as compared to the centre line of conduct ______.

1) Should be always above
2) Should be always below
3) Should always be parallel
4) May be above or below

... Answer is
Should be always above

41 - A Piezometer cannot be used for pressure measurement in pipes when _______.

1) Pressure difference is low
2) Velocity is high
3) Fluid in the pipe is a gas
4) Fluid is highly viscous

... Answer is
Fluid in the pipe is a gas

42 - A Hot Wire Anemometer is used for the measurement of ______.

1) Pressure of gases
2) Velocity of gases
3) Viscosity of gases
4) Viscosity of liquids

... Answer is
Velocity of gases

43 - Friction drag is generally larger than the pressure drag in _______.

1) Flow past a sphere
2) Flow past a cylinder
3) Flow past an airfoil
4) Flow past a thin sheet

... Answer is
Flow past a cylinder

44 - If one of the wall moves in the direction of flow with uniform velocity while the other wall is stationary, then the resulting flow between parallel walls is called ______.

1) Plug flow
2) Stoke's flow
3) Couette flow
4) Euler's flow

... Answer is
Plug flow

45 - The ratio of the energy absorbed by the body to total energy falling on it is called _____.

1) absorptive power
2) emissive power
3) emissivity
4) None of these

... Answer is
absorptive power

46 - In a flow field, at the stagnation point _______.

1) Pressure is zero
2) velocity of fluid is zero
3) Pressure head is equal to velocity
4) All the velocity head is converted into pressure head

... Answer is
velocity of fluid is zero

47 - Viscosity is the most important property in the ______.

1) Travel of a bullet through air
2) Water jet issuing from a fire air
3) Formation of soap bubbles
4) Flow of castor oil through a tube

... Answer is
Formation of soap bubbles

48 - If pressure at any point in the liquid approaches the vapor pressure, liquid starts vaporising and creates pockets or bubbles of dissolved gases and vapours. This phenomenon is ______.

1) Surface tension
2) Adhesion
3) Vaporisation
4) Cavitation

... Answer is
Surface tension

49 - The fluid forces considered in the Navier-Strokes equation are ______.

1) Gravity, pressure and viscous
2) Gravity, pressure and turbulent
3) Pressure, viscous and turbulent
4) Gravity, viscous and turbulent

... Answer is
Gravity, pressure and viscous

50 - Hydraulic grade line for any flow system as compared to energy line is ______.

1) Above
2) Below
3) At same level
4) Uncertain

... Answer is
Below

51 - To avoid vaporisation in the pipe line, the pipe line over the ridge is laid such that it is not more than _____.

1) 2.4 m above the hydraulic gradient
2) 6.4m above the hydraulic gradient
3) 10.0 m above the hydraulic gradient
4) 5.0 m above the hydraulic gradient

... Answer is
2.4 m above the hydraulic gradient

52 - The locus of elevations that water will rise in a series of pitot tube is called ______.

1) Hydraulic grade line
2) Pressure head
3) Energy grade line
4) Head loss

... Answer is
Energy grade line

53 - Pressure in Pascals at a depth of 1 m below the free surface of a body of water will be equal to _______.

1) 1 Pa
2) 98.1 Pa
3) 981 Pa
4) 9810 Pa

... Answer is
9810 Pa

54 – 

1) 16.28 cm
2) 17.28 cm
3) 19.28 cm
4) 25.28 cm

... Answer is
19.28 cm

55 - If a pump is handling water and is discharging a certain flow Q at a constant total dynamic head requiring a definite B.H.P., the same pump when handling a liquid of specific gravity 0.75 and viscosity nearly same as of water would discharge

1) same quantity of liquid
2) 0.75Q
3) Q/0.75
4) 1.5Q

... Answer is
same quantity of liquid

56 - A 20 cm diameter pipe 5000 metres long conveys 0.05 cumec of water which is to be pumped through a height of 6 metres. What is the horse power required by the pump, if its efficiency is 75 %?( take 4f = 0.006)

1) 74.2 HP
2) 74 HP
3) 75 HP
4) 50 HP

... Answer is
74.2 HP

57 - For laminar flow in a pipe, V is equal to

1) Umax
2) 0.5 Umax
3) 0.25 Umax
4) 2 Umax

... Answer is
0.5 Umax

58 - Water at 20° C flowing through a 20 cm diameter pipe. Take kinematic viscosity of water at 20°C is equal to 0.0101 stoke. Assume that the changes from laminar to turbulent at Re = 2320. The critical velocity will be _____.

1) 1.117 cm/sec
2) 11.17 cm/sec
3) 111.7 cm/sec
4) 1.117 m/sec

... Answer is
1.117 cm/sec

59 - Surge wave is an example of _____.

1) Steady uniform flow
2) Steady non-uniform flow
3) Unsteady uniform flow
4) Unsteady non-uniform flow

... Answer is
Unsteady non-uniform flow

60- Quick return mechanism is an inversion of _____.

1) Four bar chain
2) Single slider crank chain
3) Double slider crank chain
4) Crossed slider crank chain

... Answer is
Single slider crank chain

61- In gears, interference takes place when _____.

1) Tip of a tooth of a mating gear digs into the portion between base and root circles
2) Gears do not move smoothly in the absence of lubrication
3) Pitch of the gear is not same
4) Gear teeth are undercut

... Answer is
Tip of a tooth of a mating gear digs into the portion between base and root circles

62 - In a multiple V belt drive, when a single belt is damaged, it is preferable to change the complete set to _____.

1) Reduce vibration
2) Reduce slip
3) Ensure uniform loading
4) Ensure proper alignment

... Answer is
Ensure proper alignment

63 - The centre of gravity of the coupler link in a 4-bar mechanism would experience _____.

1) No acceleration
2) Only linear acceleration
3) Only angular acceleration
4) Both linear and angular accelerations

... Answer is
Both linear and angular accelerations

64 - The amplitude of underdamping a small damping varies with time as _____.

1) Linearly
2) Arithmetically
3) Geometrically
4) Exponentially

... Answer is
Exponentially

65 - Whirling speed of a shaft coincide with the natural frequency of the _____.

1) Longitudinal vibration
2) Transverse vibration
3) Torsional vibration
4) Coupled between torsional vibration

... Answer is
Transverse vibration

66 - A mass of 1 kg is attached to the end of a spring with stiffness 0.7 N/mm. The critical damping coefficient of this system is ____.

1) 1.40 Ns/m
2) 18.522 Ns/m
3) 52.92 Ns/m
4) 529.20 Ns/m

... Answer is
52.92 Ns/m

67 - Rankine's theory of failure is applicable for which of the following type of materials?

1) Brittle
2) Ductile
3) Elastic
4) Plastic

... Answer is
Brittle

68 - The shock absorbing capacity of a bolt can be increased by _____.

1) Tightening it properly
2) Increasing shank diameter
3) Grinding the shank
4) Using washer

... Answer is
Grinding the shank

69 - Which if the following key is under compression rather than in being shear when under load?

1) Saddle
2) Barth
3) Feather
4) Kennedy

... Answer is
Barth

70 - Shaft is subjected to which of the following stresses?

1) Bending
2) Torsional
3) Both bending and torsional
4) None of these

... Answer is
Both bending and torsional

71 - Which of the following is self-aligning bearing?

1) Conical
2) Spherical
3) Rectangular
4) None of these

... Answer is
Spherical

72 - Which of the following is Trapezoidal thread?

1) Acme
2) Square
3) Buttress
4) All options are correct

... Answer is
Acme

73 - The efficiency of self-locking screw is _____.

1) More than 50%
2) Less than 50%
3) Equal to 50%
4) None of these

... Answer is
Less than 50%

74 - The most suitable bearing for carrying very heavy loads with slow speed is _____.

1) Hydrodynamic bearing
2) Ball bearing
3) Roller bearing
4) Hydrostatic bearing

... Answer is
Hydrostatic bearing

75 - The outside diameter of a hollow shaft is twice it's inside diameter. The ratio of its torque carrying capacity to that of a solid shaft of the same material and the same outside diameter is _____

1) 15/16
2) 3/4
3) 1/2
4) 1/16

... Answer is
15/16

76 - A solid shaft can resist a bending moment of 3 kNm and a twisting moment of 4 kNm together, then the maximum torque that can be applied is _____.

1) 7.0 kNm
2) 3.5 kNm
3) 4.5 kNm
4) 5.0 kNm

... Answer is
5.0 kNm

77 - Under torsion, brittle materials generally fail ______.

1) Along a plane perpendicular to its longitudinal axis
2) In the direction of minimum tension
3) Along surfaces forming a 45° angle with the longitudinal axis
4) Not in any specific manner

... Answer is
Along surfaces forming a 45° angle with the longitudinal axis

78 - The shear stress distribution over a rectangular cross-section of a beam follows _____.

1) A straight line path
2) A circular path
3) A parabolic path
4) An elliptical path

... Answer is
A parabolic path

79 - When two mutually perpendicular principal stresses are unequal but alike, the maximum shear stress is represented by _____.

1) The diameter of the Mohr's circle
2) Half the diameter of the Mohr's circle
3) One-third the diameter of the Mohr's circle
4) One-fourth the diameter of the Mohr's circle

... Answer is
Half the diameter of the Mohr's circle

80 - The plane of maximum shear stress has normal stress that is _____.

1) Maximum
2) Minimum
3) Zero
4) None of these

... Answer is
Zero

81 - Consider the following theories of failure: A. Maximum stress theory B. Maximum strain theory C. Maximum shear stress theory D. Maximum energy or distortion theory The most suitable for ductile material is

1) A and B
2) A and C
3) A and D
4) C and D

... Answer is
C and D

82 - For ductile materials, the most appropriate failure theory is _____.

1) Maximum shear stress theory
2) Maximum principal stress theory
3) Maximum principal strain theory
4) Shear strain energy theory

... Answer is
Maximum shear stress theory

83 - All the failure theories give nearly the same result _____.

1) When one of the principal stresses at a point is larger in comparison to the other
2) When shear stresses act
3) When both the principal stresses are numerically equal
4) For all situations of stress

... Answer is
When one of the principal stresses at a point is larger in comparison to the other

84 - From the hypothesis given by Rankine, the criteria for failure of brittle material is _____.

1) Maximum principal stress
2) Maximum strain energy
3) Maximum shear stress
4) Maximum shear strain energy

... Answer is
Maximum principal stress

85 - In a closed helical spring subjected to an axial load, other quantities remaining the same, if the wire diameter is doubled and mean radius of the coil is also doubled, then stiffness of spring when compared to original one will become _____.

1) Twice
2) Four times
3) Eight times
4) Sixteen times

... Answer is
Twice

86 - The Poisson's ratio for most of the materials is close to _____.

1) 1 : 2
2) 1 : 3
3) 1 : 4
4) 1 : 5

... Answer is
1 : 3

87 - True stress represents the ratio of _____.

1) Average load and average area
2) Average load and maximum area
3) Maximum load and maximum area
4) Instantaneous load and instantaneous area

... Answer is
Instantaneous load and instantaneous area

88 - For an element under the effect of biaxial state of normal stress, the normal stresses are on a 45 ° plane is equal to _____.

1) Difference of normal stresses
2) Sum of normal stresses
3) Half of the sum of normal stresses
4) Half of the difference of normal stresses

... Answer is
Half of the sum of normal stresses

89 - For a thin spherical shell subjected to internal pressure, the ratio of volumetric strain to diametrical strain is _____.

1) 5 : 4
2) 3 : 2
3) 2 : 1
4) 3 : 1

... Answer is
3 : 1

90 - Stud and projection welding belong to the following category of welding _____.

1) gas welding
2) arc welding
3) resistance welding
4) pressure welding

... Answer is
resistance welding

91 - Electrode gets consumed in the following welding process _____.

1) gas
2) resistance
3) thermit
4) arc

... Answer is
arc

92 - The strength of a properly welded joint as compared to base metal would be _____.

1) same
2) more
3) less
4) unpredictable

... Answer is
more

93 - Oxygen to acetylene ratio in case of carburising flame is _____.

1) 0.5 : 1
2) 0.9 : 1
3) 1 : 1
4) 1 : 1.2

... Answer is
0.9 : 1

94 - For steel castings, the following type of sand is better _____.

1) fine-grain
2) coarser-grain
3) medium grain
4) fine-grain, coarser-grain and medium grain all are equally good

... Answer is
coarser-grain

95 - Hot tear refers to _____.

1) casting defect
2) process of fabrication
3) process of heat treatment
4) weathering of non-ferrous materials

... Answer is
casting defect

96 - Slick in a foundry shop is used to _____.

1) make and repair corners in a mould
2) thoroughly mix up moulding sand
3) make venting holes in the mould
4) prepare gates

... Answer is
make and repair corners in a mould

97- Which of the following processes would produce best components?

1) die casting
2) hot rolling
3) extrusion
4) forging

... Answer is
die casting

98 - A sprue hole is _____.

1) a casting defect
2) a hold made for riveting
3) a blind hole in jigs
4) an opening in mould for pouring molten metal

... Answer is
an opening in mould for pouring molten metal

99 - Coining is the operation of _____.

1) cold forging
2) hot forging
3) cold extrusion
4) piercing

... Answer is
cold forging

100 - The ratio  is known as_______.

1) Grashoff number
2) Biot number
3) Stanton number
4) Prandtl number

... Answer is
Biot number

[ NOTE: - ALL THE ANSWERS ARE BASED ON THE ANSWER KEY PROVIDED BY THE SSC (THIS IS ONLY FOR EDUCATIONAL PURPOUSE). IF YOU HAVE ANY DOUBT YOU CAN COMENT US.]