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Mock Test: SSC JE (ME)- 3

100 Questions MCQ Test Mechanical Engineering SSC JE (Technical) | Mock Test: SSC JE (ME)- 3

Description

Attempt Mock Test: SSC JE (ME)- 3 | 100 questions in 100 minutes | Mock test for Mechanical Engineering preparation | Free important questions MCQ to study Mechanical Engineering SSC JE (Technical) for Mechanical Engineering Exam | Download free PDF with solutions

QUESTION: 1

An Ideal gas at 27ºC is heated at constant pressure till the volume becomes three times. The temperature of the gas will then be

A.
81º C
B.
627º C
C.
543º C
D.
327 º C

Solution:

QUESTION: 2

If the time taken by a system to execute a process through a finite gradient is infinitely large,the process

A.
becomes reversible
B.
is irreversible
C.
becomes isothermal
D.
is adiabatic

Solution:

QUESTION: 3

Gas contained in a closed system consisting of piston cylinder arrangement is expand. Workdone by the gas during expansion is 50 kJ. Decreases in internal energy of the gas duringexpansion is 30 kJ. Heat transfer during the process is equal to

A.
– 20 kJ
B.
+ 20 kJ
C.
– 80 kJ
D.
+ 80 kJ

Solution:

QUESTION: 4

Direction: Each of the next consists of two statements, one labeled as the 'Assertion (A)' and
the other as 'Reason (R)'. You are to examine these two statements carefully and select the answers to these items using the codes given below:
Codes:
(a) Both A and R are individually true and R is the correct explanation of A.
(b) Both A and R are individually true but R is not the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true

Assertion (A): The changes in heat and work cannot be expressed as difference between the
end states.
Reason (R) : Heat and work both are exact differentials.

A.
A
B.
B
C.
C
D.
D

Solution:

QUESTION: 5

For a given value of TH (Source temperature) for a reversed Carnot cycle, the variation of TL(Sink temperature) for different values of COP is represented by which one of the following graphs ?

Solution:

QUESTION: 6

Efficiency of a Carnot engine is 75%. If the cycle direction is reversed, COP of the reversedCarnot cycle is

A.
1.33
B.
0.75
C.
0.33
D.
1.75

Solution:

QUESTION: 7

Gibb's free energy 'G' is defined as

A.
G = H – TS
B.
G = U – TS
C.
G = U + PV
D.
G = H + TS

Solution:

QUESTION: 8

The state of a substance whose evaporation from its liquid state is complete, is known as

A.
vapour
B.
perfect gas
C.
air
D.
steam

Solution:

QUESTION: 9

The ratio of specific heat at constant pressure (cp) and specific heat at constant volume (c,) is

A.
equal to one
B.
less than one
C.
greater than one
D.
none of these

Solution:

QUESTION: 10

A process, in which the temperature of the working substance remains constant during itsexpansion or compression, is called

A.
isothermal process
B.
hyperbolic process
C.
adiabatic process
D.
polytropic proce

Solution:

QUESTION: 11

Carnot cycle consists of

A.
two constant volume and two isentropic processes
B.
two isothermal and two isentropic processes
C.
two constant pressure and two isentropic processes
D.
one constant volume, one constant pressure and two isentropic processes

Solution:

QUESTION: 12

The absolute zero pressure will be

A.
when molecular momentum of the system becomes zero
B.
at sea level
C.
at the temperature of – 273 K
D.
at the centre of the earth

Solution:

QUESTION: 13

A condenser of a refrigeration system rejects heat at rate of 120 kW, while its compressorconsumes a power of 30 kW. The coefficient of performance of the system would be

A.
1/4
B.
1/3
C.
3
D.
4

Solution:

QUESTION: 14

Consider the following statements: Moisture should be removed from refrigerants
to avoid
1. Compressor seal failure
2. Freezing at the expansion valve.
3. Restriction to refrigerant flow.
4. Corrosion of steel parts.
Which of these statements are correct?

A.
1, 2, 3 and 4
B.
1 and 2
C.
2, 3 and 4
D.
1, 3 and 4

Solution:

QUESTION: 15

Match List-I (Process) with List-II (Type)for Bell Coleman or Joule or Reverse Brayton cycle
for gas cycle refrigeration and select the correct answer using the codes given below the lists:

A.
A
B.
B
C.
C
D.
D
E.
None of the options are correct

Solution:

QUESTION: 16

The power per tonne of refrigeration is

A.
3.5/ C.O.P
B.
C.O.P./ 3.5
C.
3.5 × C.O.P
D.
none of these

Solution:

QUESTION: 17

Which of the following represents a heat pump ?

Solution:

QUESTION: 18

In a petrol engine car, which one of the following performance characteristic is affected by thefront-end volatility gasoline used ?

A.
Hot starting and vapour lock
B.
Engine warm-up and spark plug fouling
C.
spark plug fouling and hot starting
D.
Vapour lock, engine warm -up and spark plug fouling

Solution:

QUESTION: 19

Match List-I (Gas cycles) with List-II (Thermodynamic coordinates) and select correct
answer using the codes given below the lists:

A.
A
B.
B
C.
C
D.
D

Solution:

QUESTION: 20

Direction: Each of the next consists of two statements, one labeled as the 'Assertion (A)' and
the other as 'Reason (R)'. You are to examine these two statements carefully and select the answers to these items using the codes given below:
Codes:
(a) Both A and R are individually true and R is the correct explanation of A.
(b) Both A and R are individually true but R is not the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true

Statement (I) : Specific output of a SI engine is higher than the CI engine
Statement (II): Its higher engine mixture result in ability to burn richer mixture result in increased
energy conversion rate.

A.
A
B.
B
C.
C
D.
D

Solution:

QUESTION: 21

An ideal spark ignition engine has a compression ratio of 9. What is its Air standard efficiency ifratio of specific heats is 1.5 ?

A.
63%
B.
67%
C.
70%
D.
72%

Solution:

QUESTION: 22

For minimizing knocking tendency in SI engine, where should the spark plug be located ?

A.
Near inlet valve
B.
Away from both the valves
C.
Near exhaust valve
D.
Midway between inlet and exhaust valves

Solution:

QUESTION: 23

Which of the following fuel has little tendency towards detonation ?

A.
Benzene
B.
Iso-octane
C.
Normal heptane
D.
Alcohol

Solution:

Answer : Option B

QUESTION: 24

Stoichiometric ratio is

A.
Chemically correct air -fuel ratio by weight
B.
Chemically correct air-fuel ratio by volume
C.
actual air-fuel ratio for maximum efficiency
D.
none of the above

Solution:

Answer : b

Stoichiometric ratio is Chemically correct air-fuel ratio by volume.

QUESTION: 25

Which of the following form part (s) of boiler mountings ?
1. Economiser
2. Feed check valve
3. Steam trap
4. Superheater

Select the correct answer using the codes given below:

A.
2 alone
B.
1 and 3
C.
2, 3 and 4
D.
1, 2, 3 and 4

Solution:

QUESTION: 26

Which one of the following statement is not correct ?In a fluidized-bead boiler

A.
the combustion temperatures are higher than those in the conventional boilers
B.
inferior grade of coal can be used without slogging problems
C.
the formation of NO_x is less than that in the conventional boilers
D.
the volumetric heat release rates are higher than those in the conventional boiler

Solution:

QUESTION: 27

In a boiler, the air preheater in invariably located between:

A.
Forced draft fan and chimney
B.
Forced draft fan and furnace
C.
Economizer and feed pump
D.
Condenser and feed pump

Solution:

Air preheater is invariably located between forced draft fan and furnace to preheat the combustion air.

QUESTION: 28

Out of the following impurities generally found in water, which one requires special considerationin case of very high pressure boilers?

A.
Hydrogen
B.
Ammonia
C.
Silica
D.
Dissolved salts

Solution:

QUESTION: 29

The function of economizer in a boiler is to

A.
Superheat the steam
B.
Reduce fuel consumption
C.
Increase steam pressure
D.
Maintain saturation temperature

Solution:

QUESTION: 30

When a hydrocarbon fuel burns in deficit air, Orsat analyzer will show the presence offollowing gases in the engine exhaust

A.
CO₂, N₂ and O₂
B.
CO, CO₂, N₂and O₂
C.
CO, CO₂and N₂
D.
CO_2, CO, N₂, O₂and H₂O

Solution:

QUESTION: 31

Once-through boilers will not have

A.
Drums, headers and pumps
B.
Drums, steam separators and pumps
C.
Drums, headers and steam separators
D.
Drums, headers, steam separators and pumps

Solution:

QUESTION: 32

The forced circulation of water does not take place in

A.
La-Mont boiler
B.
Lancashire boiler
C.
Velox boiler
D.
Benson boiler

Solution:

QUESTION: 33

Which of the following are boiler accessories ?

A.
economiser
B.
superheater
C.
both (a) and (b)
D.
stop valve

Solution:

QUESTION: 34

The pressure of feed water has to be raised fore its entry into the boiler. The pressure israised by a device known as

A.
feed pump
B.
injector
C.
feed check valve
D.
pressure gauge

Solution:

QUESTION: 35

In the phenomenon of cavitation, the characteristic fluid property involved is

A.
surface tension
B.
viscosity
C.
bulk modulus of elasticity
D.
vapour pressure

Solution:

QUESTION: 36

What is the unit of dynamic viscosity of a fluid termed "poise" equivalent to ?

A.
dyne/cm²
B.
gm-s/cm²
C.
dyne-s/cm²
D.
gm-cm/s

Solution:

QUESTION: 37

The vapour pressure is the characteristic fluid property involved in the phenomenon of

A.
water hammer in a pipe flow
B.
cavitation
C.
rise of sap in a tree
D.
spherical shape of rainwater drop

Solution:

QUESTION: 38

In a pipe-flow, pressure is to be measured at a particular cross- section using the most appropriate instrument. Match List-I (Expected pressure range) with List-II (Appropriate measuring device) and select the correct answer using the codes given below the lists:

A.
A
B.
B
C.
C
D.
D

Solution:

QUESTION: 39

The centre of pressure for an inclined surface area

A.
Lies below the centroid of the surface
B.
Coincides with the centroid
C.
Lies above the centroid of the surface
D.
None of the above

Solution:

QUESTION: 40

The frictional head loss in a turbulent flow through a pipe varies

A.
Directly as the average velocity
B.
directly as the square of the average velocity
C.
inversely as the square of the average velocity
D.
inversely as the square of the internal diameter of the pipe

Solution:

QUESTION: 41

The friction factor for fully developed turbulent flow through a rough circular pipe depends on

A.
Reynolds number
B.
Relative roughness
C.
both Reynolds number and relative roughness
D.
none

Solution:

QUESTION: 42

The variation in the volume of a liquid with the variation of pressure is called its

A.
surface tension
B.
compressibility
C.
capillarity
D.
viscosity

Solution:

QUESTION: 43

The atmospheric pressure at sea level is

A.
103 kN/m²
B.
10.3 m of water
C.
760 mm of mercury
D.
all of these

Solution:

QUESTION: 44

The centre of gravity of the volume of the liquid displaced is called

A.
centre of pressure
B.
centre of buoyancy
C.
metacentre
D.
none of these

Solution:

QUESTION: 45

The discharge over a rectangular notch is

where b = width of notch

h = Height of liquid above the sill of notch

Solution:

QUESTION: 46

The unit speed of the turbine runner is

Solution:

QUESTION: 47

The cavitation in a hydraulic machine

A.
causes noise and vibration of various parts
B.
reduces the discharge of a turbine
C.
causes sudden drop in power output and efficiency
D.
all of the above

Solution:

QUESTION: 48

Fig. shows the three coplanar force P.Q and R acting at a point O. If these forces are in
equilibrium , then

Solution:

QUESTION: 49

Moment of inertia is the

A.
second moment of force
B.
second moment of area
C.
second moment of mass
D.
all of these

Solution:

QUESTION: 50

The friction experienced by a body, when at rest, is known as

A.
static friction
B.
dynamic friction
C.
limiting friction
D.
coefficient friction

Solution:

QUESTION: 51

Which of the following are vector quantities ?

A.
Linear displacement
B.
Linear velocity
C.
Linear acceleration
D.
all of these

Solution:

QUESTION: 52

The volumetric strain in case of a thin cylindrical shell of diameter 'd', thickness 't', subjected to
internal pressure 'P' is

Solution:

QUESTION: 53

The Poisson ratio of a material which has Young's modulus of 120 GPa and shear modulus of 50GPa, is

A.
0.1
B.
0.2
C.
0.3
D.
0.4

Solution:

QUESTION: 54

What is the relationship between elastic constants E, G and K?

Solution:

QUESTION: 55

Normal stresses of equal magnitude s, but of opposite signs, act at a point of a strained materialin perpendicular direction. What is the magnitude of the stress on a plane inclined at 45º to theapplied stresses ?

A.
2σ
B.
σ/2
C.
σ/4
D.
zero

Solution:

QUESTION: 56

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

Solution:

QUESTION: 57

A seamless pipe of diameter d m is to carry fluid under a pressure of P kN/cm². The necessary
thickness t of metal in cm, if the maximum stress is not to exceedσ kN/cm² is

Solution:

QUESTION: 58

A slender bar of 100 mm² cross-section is subjected to loading as shown in the figure below.If the modulus of elasticity is taken as 200 × 10⁹. pa. then the elongation produced in the bar will be

A.
10 mm
B.
5 mm
C.
1 mm
D.
nil

Solution:

QUESTION: 59

Modular ratio of the two materials is the ratio of

A.
linear stress to linear strain
B.
shear stress to shear strain
C.
their modulus of elasticity
D.
their modulus of rigidities

Solution:

QUESTION: 60

A bar of copper and steel form a composite system, which is heated to a temperature of 40ºC.The stress induced in the copper bar will be

A.
tensile
B.
compressive
C.
shear
D.
zero

Solution:

QUESTION: 61

The lower layer of the beam as shown fig, will be

A.
in tension
B.
in compression
C.
neither in tension
D.
neither in compression

Solution:

QUESTION: 62

The polar modulus for a hollow shaft of outer diameter (D) and inner diameter (d ) is

Solution:

QUESTION: 63

The load required to produce a unit deflection in a spring is called

A.
flexural rigidity
B.
torsional rigidity
C.
spring stiffness
D.
Young's modulus

Solution:

QUESTION: 64

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

A.
no acceleration
B.
only linear acceleration
C.
only angular acceleration
D.
both linear and angular accelerations

Solution:

QUESTION: 65

Which one of the following sets of acceleration is involved in the motion of the piston inside thecylinder of a uniformly rotating cylinder mechanism ?

A.
Coriolis and radial acceleration
B.
Radial and tangential acceleration
C.
Coriolis and gyroscopic acceleration
D.
Gyroscopic and tangential acceleration

Solution:

QUESTION: 66

A man is climbing up a ladder up a ladder which is resting against a vertical wall. When he wasexactly half way up, the ladder started slipping . The path traced by the man is :

A.
Parabola
B.
Hyperbola
C.
Ellipse
D.
Circle

Solution:

QUESTION: 67

ABCD is bar mechanism, in which AD is the fixed link, and link BC, is in the form of a circulardisc with centre P. In which one of the following cases P will be the instantaneous centre of the disc?

A.
if it lies on the perpendicular bisector of link BC
B.
If it lies on the intersection of the perpendicular bisectors of BC & AD
C.
If it lies on the intersection of the perpendicular bisectors of AB & CD
D.
If it lies on the intersection of the extensions of AB and CD

Solution:

QUESTION: 68

In a single slider four-bar linkage when the slider is fixed, it form a mechanism of

A.
hand pump
B.
reciprocating engine
C.
quick return
D.
oscillating cylinder

Solution:

QUESTION: 69

Which of the following pairs of devices and their functions are correctly matched ?
1. Flywheel : For storing kinetic energy
2. Governors : For controlling speed
3. Lead screw in : For providing feed to the lathe slides
4. Fixtures : For locating work- piece and guiding tools

Select the correct answer using the codes given below:

A.
1, 3 and 4
B.
2 and 3
C.
1 and 2
D.
2 and 4

Solution:

QUESTION: 70

Match List-I (Kinematic pairs) with List-II (Practical example) and select the correct answer
using the code given below the lists:

A.
A
B.
B
C.
C
D.
D

Solution:

QUESTION: 71

In a cam drive, it is essential to offset the axis of a follower to

A.
decrease the side thrust between the follower and guide
B.
decrease the wear between follower and cam suface
C.
take care of space limitation
D.
reduce the cost

Solution:

QUESTION: 72

Which one if the following pairs is correctly matched ?

A.
Governor : Interference
B.
Gears : Hunting
C.
Klein's Construction: acceleration of piston
D.
Cam : Pinion

Solution:

QUESTION: 73

The working surface above the pitch surface of the gear tooth is termed as

A.
addendum
B.
dedendum
C.
flank
D.
face

Solution:

QUESTION: 74

Stress concentration in a machine component of ductile materials not so harmful as it is in brittlematerial because

A.
In Ductile material local yielding may distribute stress concentration
B.
Ductile material have large Young's modulus
C.
Poisson's ratio is larger in ductile materials
D.
Modulus of rigidity is larger in ductile material

Solution:

QUESTION: 75

Consider the following joints:
1. Railway carriage wheel and axle
2. IC engine cylinder and liner
which of the above joints is /are the result (s) of interference fit ?

A.
1 Only
B.
2 Only
C.
Neither 1 nor 2
D.
Both 1 and 2

Solution:

Correct Answer :- a

Explanation : Railway Carriage wheel and axle is an interference fit joint.

QUESTION: 76

For bolts of uniform strength, the shank diameter is made equal to

A.
major diameter of threads
B.
pitch diameter of threads
C.
minor diameter of threads
D.
nominal diameter of threads

Solution:

QUESTION: 77

The stress which vary from a minimum value to a maximum value of the same nature (i.e. tensileor compressive) is called

A.
repeated stress
B.
yield stress
C.
fluctuating stress
D.
alternating stress

Solution:

QUESTION: 78

The value of stress concentration factor depends upon

A.
material of the part
B.
geometry of the part
C.
material and geometry of the part
D.
none of these

Solution:

QUESTION: 79

The design calculations for members subject to fluctuating loads with the same factor of safety,yield the most conservative estimates when using

A.
Gerber relation
B.
Soderberg relation
C.
Good man relation
D.
none of these

Solution:

QUESTION: 80

The design of the pressure vessel is based on

A.
longitudinal stress
B.
hoop stress
C.
longitudinal and hoop stress
D.
none of these

Solution:

QUESTION: 81

Which one of the following is an advantage of forging ?

A.
Good surface finish
B.
Low tooling cost
C.
Close tolerance
D.
Improved physical property

Solution:

QUESTION: 82

Which of the following statements is correct ?

A.
No flux is used in gas welding of mild steel
B.
Borax is the commonly used flux coating on welding electrodes
C.
Laser beam welding employs a vacuum chamber and thus avoids use of a shieldignmethod.
D.
AC can be used for GTAW process

Solution:

QUESTION: 83

Which one of the following is not a fusion welding process

A.
Gas welding
B.
Arc welding
C.
Brazing
D.
Resistance welding

Solution:

QUESTION: 84

In an inert welding process, the commonly used gas is

A.
Hydrogen
B.
Oxygen
C.
Helium or Argon
D.
Krypton

Solution:

QUESTION: 85

Solid material chemical bonds are

A.
lonic, molecular and fusion
B.
Covalent, fusion and fission
C.
lonic, covalent and molecular
D.
Fission, molecular and ionic

Solution:

QUESTION: 86

Which one of the following sets if constituents is expected in equilibrium cooling of a hypereutectoid steel from austenitic state ?

A.
Ferrite and pearlite
B.
Cementite and pearlite
C.
Ferrite and bainite
D.
Cementite and martensite

Solution:

QUESTION: 87

Primary object of full annealing is to

A.
Increase toughness and yield point
B.
Reduce ductility and resilience
C.
Remove foreign impurities and improve surface finish
D.
Increase ductility and machinability

Solution:

QUESTION: 88

Match List-I (Alloy) with List-II (Use) and select the correct answer using the codes give
below the lists:

A.
A
B.
B
C.
C
D.
D

Solution:

QUESTION: 89

The most important function of the cutting fluid is

A.
Provide lubrication
B.
Cool the tool and work piece
C.
Wash away the chips
D.
Improve surface finish

Solution:

QUESTION: 90

Misrun is casting defect which occurs due to

A.
Very high pouring temperature of the metal.
B.
insufficient fluidity of the molten metal.
C.
absorption of gases by the liquid metal.
D.
improper alignment of the mould flasks.

Solution:

QUESTION: 91

Cast iron during machining produces

A.
continuous chips
B.
discontinuous chips
C.
continuous chips with built-up-edge
D.
none of these

Solution:

QUESTION: 92

The lip angle is the angle

A.
between the tool face and the ground end surface of flank
B.
made by the face of the toll and the plane parallel to the base of the cutting tool
C.
between the face of the tool and a line tangent to the machined surface at the cutting point
D.
none of the above

Solution:

QUESTION: 93

Crater wear occurs mainly on the

A.
nose part, from relief face and side relief face of the cutting tool
B.
face of the cutting tool at a short distance from the cutting edge only
C.
cutting edge only
D.
front face only

Solution:

QUESTION: 94

The cupola is used to manufacture

A.
pig iron
B.
cast iron
C.
wrought iron
D.
steel

Solution:

QUESTION: 95

The coordination number of a face centered cubic space lattice is

A.
six
B.
twelve
C.
eighteen
D.
twenty

Solution:

QUESTION: 96

Which of the following statement is wrong?

A.
A steel with 0.8 % carbon is wholly pearlite
B.
The amount of cementite increases with the increase in percentage of carbon in iron.
C.
A mechanical mixture of 87% cementite and 13% ferrite is called pearlite.
D.
The cementite is identified as round particles in the structure