d:mohd. kalim 2018all branch · during reversible non-flow process, work done w = p v p v 1 1 2 2 n...
TRANSCRIPT
1. (c)
2. (a)
3. (a)
4. (a)
5. (a)
6. (a)
7. (c)
8. (d)
9. (c)
10. (a)
11. (c)
12. (d)
13. (c)
14. (c)
15. (a)
16. (c)
17. (c)
18. (b)
19. (d)
20. (b)
21. (c)
22. (b)
23. (b)
24. (c)
25. (d)
ESE-2019 PRELIMS TEST SERIESDate: 16th December, 2018
26. (d)
27. (b)
28. (b)
29. (a)
30. (d)
31. (b)
32. (d)
33. (c)
34. (c)
35. (d)
36. (a)
37. (c)
38. (a)
39. (c)
40. (b)
41. (b)
42. (c)
43. (c)
44. (c)
45. (a)
46. (a)
47. (d)
48. (c)
49. (b)
50. (b)
51. (b)
52. (a)
53. (d)
54. (b)
55. (b)
56. (b)
57. (a)
58. (d)
59. (d)
60. (b)
61. (d)
62. (c)
63. (b)
64. (d)
65. (c)
66. (d)
67. (a)
68. (d)
69. (b)
70. (b)
71. (b)
72. (a)
73. (b)
74. (a)
75. (b)
ANSWERS
76. (d)
77. (b)
78. (a)
79. (b)
80. (c)
81. (b)
82. (d)
83. (c)
84. (b)
85. (b)
86. (a)
87. (c)
88. (d)
89. (d)
90. (c)
91. (b)
92. (b)
93. (c)
94. (d)
95. (b)
96. (c)
97. (c)
98. (b)
99. (d)
100. (d)
101. (d)
102. (a)
103. (c)
104. (a)
105. (b)
106. (c)
107. (d)
108. (a)
109. (b)
110. (d)
111. (b)
112. (b)
113. (c)
114. (a)
115. (d)
116. (a)
117. (d)
118. (b)
119. (c)
120. (d)
121. (d)
122. (c)
123. (b)
124. (d)
125. (d)
126. (a)
127. (b)
128. (a)
129. (b)
130. (b)
131. (a)
132. (b)
133. (a)
134. (b)
135. (c)
136. (a)
137. (d)
138. (c)
139. (c)
140. (b)
141. (b)
142. (b)
143. (b)
144. (c)
145. (c)
146. (b)
147. (c)
148. (c)
149. (b)
150. (d)
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[ME], ESE-2019 PRELIMS TEST SERIES PAPER-II (FLT-03) (2)
1. (c)2. (a)
xdu 3dx
yzdw dv 0 0 0dy dz
3. (a)4. (a)
P MA Z
Comp,max 4
P eP P PedA Ad Ad 2864
P e1A d 8
ten, maxP e1A d 8
comp, max
ten,max
8e1 13d8e 31d
de5
5. (a)
Cr E
1 1 1 1 11P P P 600 400 240
P = 240 kN
6. (a)7. (c)
Due to Poisson’s effect, longitudinal strainleads to lateral strain which will lead toanticlastic curvature for an originallyrectangular cross-section.
For a doubly symmetric section, shearcentre always coincide with the centroid ofthe section.
8. (d)From Mohr circle :
(120, 0)
( , 50)n
( , 0) (70, 0)
Radius of Mohr Circle = 50 MPa = 120
2
20MPa
Maximum shear stress = 120 20
2
= 50 MPa
max 50 20 30 MPa
9. (c)
1 2 1 2max, abs max , ,
2 2 2
For thin spherical cells, 1 2and are same equal
to pd4t .
max, abspd8t
10. (a)
5 KN/mA
25 25
Shear force V at point A = 25 – 2.5 × 5
= 12.5 KN
NA50
100
Shear Stress
=
3
3VAy 12.5 10 150 100 100Ib 300150 150
12 = 0.3703 mpa
11. (c)Applying Bernoulli's equation when valve is closed.
V1 = V2 = 02 2
1 1 2 11 2
P V P VZ Z2g 2g
h
o
2 11 2
P PZ Z
3
1 270 10z z 7m
10 1000
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[ME], ESE-2019 PRELIMS TEST SERIES PAPER-II (FLT-03) (3)
Now when valve is open2 2
1 1 2 21 2 L
P V P VZ Z h2g 2g
1 21 2 L
P PZ Z h
1 2V V
23 + 7 = hL Lh 30m .
12. (d)u = 2y, v = 8x + 2
Equation of streamline, dy vdx u
dydx =
8x 22y
2y dy = (8x + 2) dx
Integrating both sides, we get
y2 = 4x2 + 2x + c
y2 = 2x (2x + 1) + c
13. (c)
Displacement thickness, * =
00
u1 dyu
= 0
y1 dy
=
2
0
yy2
=2
Momentum thickness, =
0
0 0
u u1 dyu u
= 0
y y1 dy
=
2 3
20
y y2 3
= 6
shape factor =
* / 2 3
/ 6
Alternatively; for
m
o
u y * m 2u m
Hence shape factor =
1 2 3
114. (c)
For maximum efficiency, H = 3hf
H = 2
53f l Q12.1d
100 =
2
53 0.03 50 Q
12.1 (0.5)
Q = 2.9 cumecs = 2900 l/sec.
15. (a)
Head loss in pipes connected in parallelwill be same irrespective of their sizes andlengths.
Water hammer pressure is more in rigidpipes than flexible pipes.
16. (c)The instantaneous velocity Vd in the delivery pipemay be obtained as :
Vd =d
A r sina
(Vd)mean = d2
00
A r sin da
d
= d
A ra
(Vd)max = d d
A A rr sin 90ºa a
d mean
d max
(V ) 1 .(V )
17. (c)
To reduce the acceleration head we needto reduce the length of suction pipe (ls) andlength of delivery pipe (ld) in which fluctuationof velocity occurs. This is done by the fittingair vessels closed to cylinder as possible.Thus between air vessel and cylinder onlyfluctuating velocity will occur. Below airvessel on suction side and above air vesselon delivery side velocity will be constant.
Due to movement of piston, when there isexcess velocity above average b/w suctionside air vessel and cylinder, water issupplied from air vessel.
18. (b)When local pressure falls below the vapourpressure, boiling starts taking place which leadsto cavitation.
So (b) is correct
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[ME], ESE-2019 PRELIMS TEST SERIES PAPER-II (FLT-03) (4)
19. (d)
w wh = 1 1h
h1 =
w
1
w
h 10
20. (b)A. Pitot tube – used to find velocity by measuring
stagnation pressure head (4)
B. Micro-meter – Measures differential pressure(3)
C. Pipe bend meter – measure rate of flow (2)
D. Wall pressure tap – measures flow staticpressure (1)
21. (c)In characteristics curve of a pump, the curve isdrawn between (head/efficiency/input power) onordinate vs discharge (Q) on abscissa.
Hence ‘c’ is correct.
22. (b)Force along the slope opposing the motion isF = R(mgsin F )
where resistance due to friction, air etc. is
FR = 30 N/kg × 200 kg
= 6000 N
sin = 1
200
F =
1200 10 6000200
= 10 + 6000 = 6010N
Power = F × V
= 6010 × 10 = 60.1 kW
23. (b)24. (c)
Maximum efficiency
max = =1000 300 0.7 or 70%1000
Heat input Q = 500 kJ
Maximum work output
Wmax = Q max = 500 × 0.7 = 350 kJ
Minimum heat rejected
= Q – Wmax = 500 – 350 = 150 kJ
25. (d)Total heat supplied
Q1 = =57 1080 1026W60
T1 = 285 K
Q1 HE
Q2 W
T = 275 K2
For reversible heat engine
1 2
1 2
Q QT T
= = = 1
2 21
Q 75Q T 1026 990 WT 285
Work output = Q1 – Q2
= 1026 – 990 = 36W
26. (d)If the gas obeys Van der Waal’s equation at thecritical point, then,
c c c2
c
ap b RT
At critical point, =
cT T
p = 0
and=
c
2
2T T
p = 0
hence, b = c and 3
a = 2c c3p
2c c c
c cc2c
3pp RT3
cc
24p
3 = RTTc
c c8p3
= RTTc
c
c c
RTp = =8 2.67
3
27. (b)I. The flow through insulated constant diameter
pipe
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[ME], ESE-2019 PRELIMS TEST SERIES PAPER-II (FLT-03) (5)
1 2
Applying steady flow energy equation
h1 + Q = h2 + w
Q = 0 = w
So, h1 = h2 = constant
Its enthalpy which remains constant along withflow.
For an isolated system, isoS 0 .
28. (b)First law for a stationary system in a processgives
Q = U WQ1–2 = U2 – U1 + w1–2 ...(i)w1–2 = P(v2 – v1)
= 0.15 (0.2 – 0.4)MJ= –30 kJ
and givenQ1–2 = –45 kJ
from (i)–45 kJ = U2 – U1 – 30kJ
U2 – U1 = –45 + 30
= – 15 kJ29. (a)
During reversible non-flow process, work done
W =
1 1 2 2p v p vn 1
As n increases, W decreases.
Further adiabatic mixing is irreversible process.
30. (d)Over heat transfer coefficient (U)
i 0
1 1 L 1U h K h
1 1 0.15 1U 25 0.15 25
1 27 25UU 25 27Hence, it is closer to the heat transfercoefficient based on the bricks alone.
Hence, (d) is the correct answer.
31. (b)32. (d)
L = 10 cm, F12 = 0.1716
F1-1 + F1-2 + F1-3 = 1F1-1 = 0
F1-3 = 1 – F1-2 = 1 – 0.1716 = 0.8284
AA1F1-3 = A3F3-1
F3-1 = 1
1 33
A FA
=
2(10)4 0.8284
10 10= .2071
33. (c)
x x1/3 1/31 Kh h
x x
x
average 1/30
1 Kh dxL x
= 4
1/30
1 K dx4 x =
42/3
0
1 xK243
= 42/30
3 K x8
= 2/33 K(4)8
at x 4 1/3Kh
(4)
1
3
2/3avg 1/3
at x 4
3 K(4)h 38 (4)h 8K 4
34. (c)
n n
x 2
x 2lim 80x 2
n 1
x 2lim nx 80
n 1 5 1
x 2lim nx 5.2
n = 5
n shields
without shields
Q 1 1 1Q n 1 5 1 6
35. (d)
LC = Volume (V)
Surface area (As)
=
3
2
4 R R 0.33 0.053 3 24 R
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[ME], ESE-2019 PRELIMS TEST SERIES PAPER-II (FLT-03) (6)
Bi =
chL 200 0.05 0.025K 400
Bi < 0.1
Bi = Conduction resis tance (internal)Surface convective resis tance
Bi < 0.1
Hence, (d) will be correct answer.
36. (a)At the insulated surface, heat conducted = 0
so, dTkAdx
= 0 (for insulated face)
dTdx
= 0 (condition for maxima/minima)
T is max at insulated face.
37. (c)Density of air decreases with increase intemperature and hence specific gravity alsodecreases.
38. (a)Thin film orboundary lubrication(unstable)
Thick film lubrication(stable) PS
QR
A
K
p
Coef
f. of
frict
ion
()
(min)
Partial lubrication
N
39. (c)40. (b)
Given, h = 12 mm, = 150 N/mm2
Shearing load is given by
Ps = 0.707 × h × L ×
or sPL
= 0.707 × 12 × 150 = 1272.6 N/mm
= 12.726 kN
cm41. (b)
Compression and transfer molding are used forshaping thermosetting plastics.
42. (c)Flow-line layout – Automobiles
Process layout – Job shop production
Fixed position layout – Aeroplanes
Hybrid layout – Flammable, explosiveproducts
43. (c)
Sensitivity of LVDT = Output currentDisplacement
=
333 10 4 10 A / mm
0.75Sensitivity of instrument = Amplification factor× sensitivity of LVDT
= 4 × 10–3 × 200 = 0.8 A/mm
44. (c)45. (a)
Solidity = Projected area of blades
Swept area
=
NC 20 0.15
R 1.5 = 0.6366
46. (a)Pneumatic sensors may be contact less devicesor contact sensors. They can be used as proximitysensors, touch sensors, or pressure or forcesensors.
47. (d)48. (c)
SO2 can be removed in the combustion processby adding limestone to the fluidized bed,el iminating the need for an externaldesulfurization process.
Because of the reduced combustiontemperature, NOx emission are inherently low.
49. (b)High specific volume of vapour leads to large sizeof compressor and work requirements alsoincreases.
50. (b)51. (b)
Bypass factor =
21 12 0.2530 12 0.7 0.25
= 0.475 kg/kg of dry air
52. (a)
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[ME], ESE-2019 PRELIMS TEST SERIES PAPER-II (FLT-03) (7)
53. (d)54. (b)
The cooling of air between two stages ofcompression is known as intercooling
Due to intercooling:
(i) Work of compression is reduced
(ii) Specific out of the plant is increased
(iii) Thermal efficiency is reduced, however this losscan be remedied by employing exhaust heatexchanger as in regeneration.
55. (b)In De-laval turbine,
Work done = change in kinetic energy
600 = 2 22
1 1 (40 V )2
V2 = 20 m/s
56. (b)
Specific steam consumption = net
3600W
= T P
3600 3600W W 939.54 3.54
= 3600936
= 3.84
57. (a)
In creep feed grinding MRR is high, feed rateis very slow, grinding wheels are mostly of softergrades, and reduced temperature at the worksurface.
58. (d)
59. (d)
Peak pressure generated by explosive dependsupon
Types of explosive
Weight of explosive
Standoff
Compressibility of energy transmitting medium
Acoustic impedance of energy transmittingmedium, which is equal to the product of itsdensity and sound velocity in the medium
60. (b)
61. (d)
No-Go
Go
Tolerance
Some of the good parts are rejected
62. (c)CIMS offers following benefits Increased machine utilization Scheduling flexibility Lower in-process inventory Reduced manufacturing lead time Reduced direct and indirect labour.
63. (b)64. (d)
The flue gas passes through the stages ofsuperheater, and then economizer. In the airpreheaters, the flue gases transfer their residualheat to the combustion air, during which theyare cooled to the exit flue gas temperature ofthe steam generator. For further cleaning, theflue gas is conducted through an electrostaticprecipitator to remove dust.
65. (c)Goodman line is safe w.r.t. fatigue failure but thereis small portion inside the Goodman line wherecomponent could fail due to yielding, hencemodified Goodman diagram combines fatigue failurewith failure by yielding.
66. (d)67. (a)
For the transverse vibration of a shaft carrying severalloads, there are two methods of finding naturalfrequency of the system: Dunkerley’s method andenergy method. Dunkerley’s method givesapproximate results but is simple. This is usedwhen the diameter of the shaft is uniform. Theenergy method gives accurate results but involvesheavy calculations in case there are many loads.This is also known as Rayleigh’s method.
68. (d)When a point on one link is sliding along anotherrotating link, such as in quick return motionmechanism, then the coriolis component ofacceleration is taken into account. These is nosuch occurence in the case of slider crank orscotch yoke mechanism.
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[ME], ESE-2019 PRELIMS TEST SERIES PAPER-II (FLT-03) (8)
69. (b)Mean time between failure (MTBF) = 1200 hr
Mean time to repair (MTTR) = 36 hrs
So, Availability =
MTBF 1200MTBF MTTR 1200 36
= 12001236
= 0.9708
70. (b)Annual demand = 94600 units
Available time = 46 weeks/year × 6 shift/week
× 8hr/shift × line
= 46 × 6 × 8 × 0.98
= 2163.84 hrs
The cycle time TC = Available time
Annual demand
=2163.8494600
= 0.0228 hrs/unit
= 1.372 minutes/unit
71. (b)
Pr ocess Critical ratio time Due Due dateOrder = remaining date
Pr ocessing time(day)P 5 25 5Q 17 35 2.05R 7 22 3.142S 9 27 3
jobs are sequenced on increasing order of theircritical ratio i.e Q – S – R – P
72. (a)
Arrival rate = 45 customer/hr = 4560
customer/min
Service ratio, = 60 customer/min
Utilization =
45 360 4
Average number of customer in the queue
Lq =
2
1
=
23 4314
= 2.25
Average waiting time of the customer in the queue
Wq =
qL 2.25
3 4 = 3 min
73. (b)D = 60 units/days, Co = 120/order, Ch = Rs 0.05/unit day, Lt = 5 days
Optimal order quantity = Q = 0
h
2DCC
= 2 60 120
0.05 = 537 units
Safety stock= Lt × d
= 5 × 60
= 300 units
74. (a)
0
/2/2
/2
OO
C B
A
Given,
OA = 300 mm
OB = OC = 150 mm
OB 150cos 0.52 OA 300
60 120
2
Hence Time of cutting strokeTime of return stroke
=
360 360 120 240 2120 120
75. (b)76. (d)77. (b)78. (a)
Part programming generation of cutter locationdata.
Hence ‘a’ is correct.
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[ME], ESE-2019 PRELIMS TEST SERIES PAPER-II (FLT-03) (9)
79. (b)
The rotation of the index crank = 40 31 turns28 7
One full rotation + 9 holes in 21 hole circle in platenumber 2.
Hence, ‘b’ is correct.
80. (c)
Tetragonal crystal structure :
a b c, 90
81. (b)
Thermoplastic material have no specific glasstransition temperature.
Thermosetting material have specific glasstransition temperature.
Thermoplastic material has mostly linearstructure Eg : polyethylene.
82. (d)
When polymers are subjected to bending orfolding then polymers may become white incolour and this phenomena is known as stresswhitening.
83. (c)
Piezoelectric transducers are more effectivethan magnetorstrict iv e t ransducers butmagnetorstrictive transducers are more ruggedcan be used at higher powers and have morelife than piezoelectric transducers. Hencemagnetorstrictive transducers are mostly usedin ultrasonic machining.
84. (b)
85. (b)
1) Complete breakdown of the steady throughflow is called Surging
2) In high pressure ratio multistage compressor,the axial velocity is relatively small in theHigher pressure stages.
3) Separation of flow from the blade surfaces isStalling.
86. (a)
87. (c)
88. (d)
The cyclone collection efficiency increases withincreasing (a) particle size, (b) particle density,(c) inlet gas velocity, (d) cyclone body length,(e) number of gas rev olutions, and (f )smoothness of cyclone walls. The collectionefficiency decreases with increasing (a) cyclonediameter, (b) gas outlet duct diameter, and (c)gas inlet area.
89. (d)
90. (c)
91. (b)
For the same output, the weight per horsepowerof a gas turbine is about one third that ofreciprocating piston type internal combustionengine.
92. (b)
The Turgo turbine is an impulse water turbinedesigned for medium head applications.Operational Turgo turbines achieve efficienciesof about 87%.
93. (c)
When n
1
, transmittivity factor is negative.
This means that there is a phase difference of180° between the transmitted force and thedisturbing force o(F cos t) .
94. (d)Critical damping reponse is much more fasterthan Overdamping response.
Damping ratio for critically damped system isequal to one.
Door closing mechanism is a overdampedsystem.
95. (b)When the load increases, the configuration ofthe governor changes and a valve is moved toincrease the supply of the working fluid.
When the load decreases, the engine speedincreases and the governor decreases the supplyof working fluid.
The function of a flywheel in an engine is entirely
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[ME], ESE-2019 PRELIMS TEST SERIES PAPER-II (FLT-03) (10)
different from that of a governor. It controls thespeed variation caused by the fluctuations of theengine turning moment during each cycle ofoperation. It does not control the speed variationscaused by a varying load
96. (c)97. (c)
Since the rolling motion takes place between thecontacting surfaces (i.e. the roller and the cam),therefore the rate of wear is greatly reduced. Inroller followers also the side thrust exists betweenthe follower and the guide. The roller followersare extensively used where more space isavailable such as in stationary gas and oil enginesand aircraft engines.
In radial cams or disc cams, the followerreciprocates or oscil lates in a directionperpendicular to the cam axis.
98. (b)99. (d)100. (d)
Primary force = 2mr cos
Primary couple = 2mr cos
Secondary force =
2mr cos2n
Secondary couple =
2mr cos2n
An in-line four-cylinder four-stroke engine hastwo outer as well as two inner cranks in line.The inner cranks are at 180° to the outer throws.Thus, the angular positions for the cranks are:
for f irst, (180 ) for the second,
(180 ) for the third and for the fourth.
Primary force
= 2mr [cos cos(180 )
= cos cos ] 0180
Primary couple
= 2 3 1mr cos cos 1802 2
= 1 3cos cos 0180
2 2
= 3 cos 0180
2
Secondary force
= 2mr cos2 cos 360 2n
cos cos2360 2
= 24mr cos2
n
Secondary couple
= 2 3 1mr cos2 cos 360 22 2
1 3cos cos2360 22 2
= 0
101. (d)S.I. engines are quantative governing engines asair-fuel mixture supplied through carburator so wecan not have qualitative governing.
102. (a)103. (c)104. (a)
In rating of SI engine fuel, ISO-octane is assigned100 octane number and normal heptane as zerooctane number.
105. (b)106. (c)
Demand in December, Ddec =30 units
Fore cast for December, Fdec=35 units
= 0.4
Fore cast for Jan 2017
Fjan = dec dec decF (D F )
= 35 + 0.4(30 – 35)
= 35 + 0.4 x – 5 = 33 units
107. (d)
(TC)I = FI + xVI = 100000 + 75x
(TC)II = FII + xVII = 190000 + 60x
For break even point for both
alternatives
(TC)I = (TC)II100000 + 75x = 190000 + 60x
15x = 90000 x = 6000
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[ME], ESE-2019 PRELIMS TEST SERIES PAPER-II (FLT-03) (11)
108. (a)Given, LP
x y 23x 5y 15x,y 0
x y2 2 = 1
x y15 153 5
= 1or x y 15 3
3x + 5y = 15x + y = 2
(2, 0) (5, 0)
(0, 2)
(0, 3)
109. (b)
I
III III
RI = 0.8, RII = 0.85, RIII = 0.9
Reliability of two parallel units
= [1 – (1 – R1)(1 – R1)] = [1 – (1 – 0.8)(1 – 0.8)] = 1 – (1 – 0.8)2
Reliability of series system
= [1 – (1 – 0.8)2] × RII × RIII = [1 – (1 – 0.8)2]× 0.85 × 0.9 = 0.7344
110. (d)When a beam of charged particles passesthrough a magnetic field, forces act on theparticles and the beam is deflected from itsstraight line path. A current flowing in a conductoris like a beam of moving charges and thus canbe deflected by a magnetic field. This effect iscalled the Hall effect.
Magnetic field
Current
Potential differenceproduced by deflection
of electronsFig. : Hall effect
111. (b)A ROM is a non-volatile memory. It storesinformation permanently.
It is not accessible to user, and hence he cannot write anything into it.
112. (b)Maximum wind power
Pmax = 3i
16 1 AV27 2
60 × 1000 = 316 1 1.2 3 A27 2
A = 6250 m2
113. (c)
Revolving joint is represented by letter ‘V’. Sincethe arm movements in dif ferent robotconfigurations are different, the work volumes orwork envelopes of different coordinate systemsare also different.
114. (a)
C30 S30 0 0S30 C30 0 0T 0 0 1 0
0 0 0 1
3 1 0 02 21 3 0 02 20 0 1 00 0 0 1
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[ME], ESE-2019 PRELIMS TEST SERIES PAPER-II (FLT-03) (12)
115. (d)
116. (a)
Stepper motors have high vibration levels due tostepwise motion
117. (d)
118. (b)Let velocity of car = VRelative velocity of car coming from oppositedirection = V + 45
Using relative velocity concept, 10 6
V 45 60
V = 55 Km/hr
Hence, ‘b’ is correct.
119. (c)The continuity for unsteady flow is
Q Ax t
= 0
QAt x
A 0.10t
120. (d)121. (d)
Sectional dimension is chosen such that the ratioof distance from NA to extreme fibre in tensionand compression is exactly same as the ratio ofallowable stresses in tension and compression.Under this provision section will be mosteconomically utilized.
122. (c)In I-section more area is located farther awayfrom neutral axis. Generally more than 80% ofBM is resisted by the flanges only.
123. (b)124. (d)
Flow always taken place in the direction fromhigh total energy to low total energy.
125. (d)
Pressure gradient dpdx
is positive due to
decrease in velocity in the region of boundarylayer separation.
126. (a)Beta distribution model for PERT
Gives
0 m pE
t 4t tx t
6
Weightage of to & tp is equal.
127. (b)
128. (a)
129. (b)
130. (b)
131. (a)
132. (b)
133. (a)
When Bi < 0.1, the variation of temperature withlocation within the body is slight and canreasonably be approximated as being uniform.
134. (b)
135. (c)136. (a)
Heat cannot be extracted from the flue gassesfor economiser, superheater etc. since theeffective draught will be reduced if the temperatureof the flue gasses is decreased.
137. (d)A is false, R is true
As rake angle ( ) increases, shear angle ( )increases hence shear area decreases and dueto lower shear area, cutting force decreases.
138. (c)In resistance projection welding, multipleprojection can be applied during embossing toplate having higher thickness and higherconductivity material hence multiple spot weldingcan be done simultaneously.
139. (c)Assertion is correct but the moving ion is cationas it is smaller in size and hence more mobilethan anion.
140. (b)A certain water level in the drum should bemaintained to give adequate steam space andreduce Priming.
IES M
ASTER
[ME], ESE-2019 PRELIMS TEST SERIES PAPER-II (FLT-03) (13)
141. (b)
Volumetric efficiency =
1nH
L
P1 C 1P
142. (b)In the fixed blade, the velocity obtained in themoving blade is transformed into pressure energy.
143. (b)Rateau/Pressure compounding of impulse turbineis done to decrease high rotational speed ofimpulse turbine and bring it to a more practicallimit.
144. (c)Governor is said to be isochronous when theequilibrium speed is constant (i.e. range of speedis zero) for all radii of rotation of the balls withinthe working range, neglecting friction.
The isochronism is the stage of infinite sensitivity
145. (c)Limiting addendum for pinion is larger than thatof gear for equal addenda, interference takesplace between the tips of the wheel teeth andthe flank of the pinion teeth.
146. (b)
In SI engine, the spark is advanced to have peakpressure around 10° after top dead center duringexpansion. Because first phase of ignition is timedependent not speed. So at higher speed, moreangle is rotated in given time. This ensures goodbrake power. The turbulances in chamber arealso increased by high speed, so the flamevelocity.
147. (c)Free float = Total float - Head event slack.
148. (c)
The tape reader must be omitted in DNC, thusrelieving the system of its least reliable component
149. (b)
150. (d)Wind energy power plants is among indirectmethods of harnassing solar energy.The direct means include only thermal andphotovoltaic.