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GATE-2016
: 080-617 66 222, [email protected] ©Copyright reserved. Web:www.thegateacademy.com
IInnddeexx
11.. QQuueessttiioonn PPaappeerr AAnnaallyyssiiss
22.. QQuueessttiioonn PPaappeerr && AAnnsswweerr kkeeyyss
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GATE-2016 CE-SET-2
: 080-617 66 222, [email protected] ©Copyright reserved. Web:www.thegateacademy.com 1
ANALYSIS OF GATE 2016
Civil Engineering
GATE-2016- CE 7-Feb 9 AM-12 PM
SUBJECT NO OF
QUESTION Topics Asked in Paper
Level of Toughness
Total Marks
Enviormental Engineering
1 M: 2 2 M: 2
BOD,Air Pollution; Sound Pollution, Hardness, Ion Exchange Method, Sedimentation tank
Moderate
6
Structural 1 M: 1 Force in Truss, Kinematic indeterminacy in Moderate 5
[CATEGORY NAME]
15%
WRE(FM &hyd & Irrigation)
13%
Environmental Engineering
6%
RCC 5%
Steel Structure 5% Mechanics
2% Structural Analysis
5%
Geotechnical Engineering
14%
Transportation Engineering
7%
Surveying 7%
General Aptitude 15%
Solid Mechanics/SOM
3% CMM 3%
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GATE-2016 CE-SET-2
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Analysis 2 M: 2 truss.
Water Resources Engineering
1 M: 3 2 M: 5
Unit hydrographs; Khosla Theory, Well hydraulics; Jet impact, Open channel fow;Hydraulic machines, fluid properties.
Easy 13
SOM/Solid Mechanics
1 M: 1 2 M: 1
Principal stress, Vol strain; SF & BM Easy 3
R.C.C. 1 M: 1 2 M: 2
Building materials; shear strength of RCC; modulus of rupture; Non prismatic RCC beam
Easy 5
Geomatics/Surve-ying Engineering
1 M:3 2 M:2
Photogrammetery;departure Moderate 7
Geotechnical Engineering
1 M: 4 2 M: 5
Earth Pressure; permeability& seepage;compaction; Bearing capacity
Moderate 14
Transportation Engineering
1 M: 3 2 M: 2
Geomatric design; Signal design, pavements Easy 7
* Construction Materials and Management
1 M: 1 2 M: 1
*Construction Management Tough 3
Engg. Mechanics 1 M: 0 2 M: 1
*Trusses and Frames. Tough 2
Steel Structure 1 M: 1 2 M: 2
Plastic Analysis ; Design of Tension Member
Moderate 5
Engineering Mathematics
1 M: 5 2 M: 5
Numerical Method ;Matrices;Complex Variable; Probability ; Limit & Continuty. Moderate 15
GA 1 M: 5 2 M: 5
Time & Work ;Paragraph; English fill in Blank, ;Number theory; Venn Diagram ; Mensuration& Area
Easy 15
Total 65 Moderate 100 * Indicates Questions from New Syllabus.
Faculty Feedback:
Few questions came from New Syllabus ( 2 questions from CPM, 1 question from
mechanics)
General Ability was pretty easy;
Weightage of Environment, Geotechnical and Highway was more as usual.
Construction management Structural analysis was scoring
Paper was logical. Qualifying is easy but scoring is tough. More focus was on
concepts.
Prectice Online test Series & Previous year question Series Will be beneficial .
.
GATE-2016 CE-SET-2
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GATE 2016 Examination
Civil Engineering
Test Date: 07/02/2016
Test Time: 9:00 AM to 12:00 PM
Subject Name: CIVIL ENGINEERING
Section: General Aptitude Q NO. 1.
[Ans. C]
Q NO. 2.
[Ans. A]
Q NO. 3.
[Ans. C
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Q NO. 4.
[Ans. A]
Q NO. 5.
[Ans. A]
Q NO. 6.
[Ans. D]
.
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Q NO. 7.
[Ans. D]
Q NO. 8.
[Ans. B]
Q NO. 9.
[Ans. D]
.
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Q NO. 10.
[Ans. C]
Section: Technical Q NO. 1.
[Ans. *] Range: 54.49 to 54.51
Q NO. 2.
[Ans. D]
Q NO. 3.
[Ans. C]
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Q NO. 4.
[Ans. A]
Q NO. 5.
[Ans. D]
Q NO. 6.
[Ans. A] Kinematic inderminacy Dk = 2j − re
= 2 × 7 − 2 = 11
Q NO. 7.
[Ans. B]
.
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Q NO. 8.
[Ans. B]
∑MA = 0 ⇒ RD × 2L − P × L = 0
⇒ RD =P
2
At joint D: ∑FY = 0
RD =P
2
45° T
RD
D
RA
L
L L
P
C B
A
.
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⇒ T cos 45° =P
2
∴ T = P/√2
Q NO. 9.
[Ans. D]
Q NO. 10.
[Ans. C] Total float can be determined once the activity time i.e., EST, EFT, LST and LFT are known Total float, FR = LST − EST = LFT − EFT
.
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For activity 5-7, EST = 38 EFT = 63 LFT = 63 LST = 38 FT = 0 For activity 11-12, EST = 80 EFT = 81 LFT = 81 LST = 80 FT = 0 Note: it can be seen directly that since the slack of all events are zero, there is not margin left for the occurrence of events and therefore. Maximum available line = Time required for completion of activity ∴ FT for all activities is zero.
Q NO. 11.
[Ans. D] In case of clay ultimate bearing capacity is independent of width of footing
Q NO. 12.
[Ans. C]
ic =G − 1
1 + e= (G − 1)(1 − n) ∵
1
1 + e= 1 − n
ic = (G − 1)(1 − 0.3) = (G − 1) × 0.7
G =ic
0.7+ 1 = 1.43ic + 1
38 38 63 63 70 70
80 80
81 81
38 38 63 63 70 70
8 8
1 2
0 0 1 2 3 10 11 12
4 6 8
4 6 8
A B
C
D
E F
G H
J
I
K L
1 7
30
30
25
25 7
7
7
7
3 1
.
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Q NO. 13.
[Ans. B]
OCR =Maximum effective stress in past
Maximum effective stress in present
Maximum effective stress in present = 10 γsat = 10γw = 10 × 16 − 10 × 10 = 60 kN/m2
∴ OCR =90
60= 1.5
Q NO. 14.
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[Ans. B]
ϕB =2.75
4× 100 = 68.75%
ϕP + 100 − ϕR = 31.25%
Now, ϕP =Pressure head at point P
Total head× 100
31.25 =h
4× 100
∴ h = 1.25 m
Q NO. 15.
[Ans. *] Range: 0.19 to 0.21
Sr + Sy = n 5
100+
Vw
103 × 106 × 1=
25
100
Vw = 0.2 × 109m3 = 0.2 km3
Q NO. 16.
[Ans. C]
.
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Q NO. 17.
[Ans. D]
Q NO. 18.
[Ans. *] Range: 6.8 to 7.0 Discharge to be treated by one tank,
Q =1500
2= 750 m2/day
Surface area, A =Q
OFR=
750
20= 37.5m3
⇒ 37.5 = π ×d2
4
⇒ d = 6.91 m
Q NO. 19.
[Ans. *] Range: 380 to 390
Earth′s Surface Troposphere
Stratosphere
Mesosphere
Thermosphere Exosphere
.
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Total water to be treated = 540 × 4 = 2160 l/day Resultant hardness required = 75 mg/l Let bypass rate be x l/day hardness of 420 mg/l Resultant hardness required = 75 mg/l
CHmix =CH1Q1 + CH2Q2
Q
75 =x × 420 + (2160 − x)0
2160
x =2160 × 75
420= 385.7 l/day
Q NO. 20.
[Ans. C] The sound pressure of the faintest sound that a normal healthy individual can hear is 20 μPa. It is taken as reference sound pressure level. A 20 μPa pressure is 0 dB on the sound pressure level scale
Q NO. 21.
[Ans. C]
Q0 = 540 I/day
1
2
3
4
Q1 = x CH1 = 420 mg/l
Bypass 75 mg/l
Softner
CH4 = 0 mg/l Q2 = 2160 − x
Q0
Q0
Q0
.
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Q NO. 22.
[Ans. A]
Q NO. 23.
[Ans. D]
Q NO. 24.
[Ans. D]
The departure of the line ; D = l sin θ
= 10 sin 30° =10
2= 5 m
Q NO. 25.
[Ans. A]
E W
N
S
D
L l 30°
.
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Tangent length, VT1 = R tanΔ
2
= R tan 30° = 0.577 R
Q NO. 26.
[Ans. B]
T2
V
Δ = 60°
T1
R R
.
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Q NO. 27.
[Ans. B] Q NO. 28.
[Ans. D]
Q NO. 29.
[Ans. *] Range: 85.0 to 85.5
Q NO. 30.
[Ans. B]
.
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Q NO. 31.
[Ans. C] Volumetric strain
∈V= (σx + σy + σz
3) (1 − 2μ)
⇒δV
V= (
σx + σy + σz
3) (1 − 2μ)
As ΔV = 0 ⇒ Either σx + σy + σz = 0 or1 − 2μ = 0
⇒ 1 − 2μ = 0 μ = 0.5
Q NO. 32.
[Ans. B]
.
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σx + σy = σ1 + σ2
⇒ 5 + 5 = 10 + σ2 ⇒ σ2 = 0
Now, σ1 2⁄ =σx + σy
2± √(
σx − σy
2)
2
+ τxy2
∴ σ1 =5 + 5
2+ √(
5 − 5
2)
2
+ τxy2
⇒ 10 = 5 + τxy
∴ τxy = 5 MPa
Q NO. 33.
[Ans. A]
σ1
σ2 σ1
σ2 σx
σx = 5
σx = 5
σy
.
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As there is no horizontal force, Hence HP = HS = 0
∑MQ = HP ×L
2= 0
Q NO. 34.
[Ans. C]
HS = 0
R
w kN/m
L L/2
VS VP
HP = 0 P S
Q
.
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Given data L = 1m, A = 0.05 m2, E = 30 × 106 N/m2 Consider joint ′S′
FSQ = = FSR
2FSQ = cos 45° = W
⇒ FSQ =W
2× √2 =
W
√2
∴ FSQ =W
√2
As the truss is symmetrical
∴ FQP = FPR =W
√2(Tensile)
Now consider joint ‘Q’
FQP = FQS =W
√2
∑Fx = 0
⇒FQP
√2+
FQS
√2+ FQR = 0
⇒ FQR = W (Compressive)
∴ FQR + 100 kN (compressive)
45°
45°
FQP
FQP
FQS
FSR
W
FSQ
45° 45°
L
45°
45° 45°
45°
90°
90°
W
Q R
S
W
√2
W
√2
W
√2
W
√2
.
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Stress in member QR
σQR =FQR
2Δ
⇒ σQR =100
2 × 1.05=
100 × 100
2 × 5= 100 kN/m2
∴ σQR = 1000 kN/m2
As the member QR consist compressive so it will go under shortening
∴ Shortening, Δ =P(Length)
2AE=
FQR. LQR
2AE
LQR = √L2 + L2 = √2L
∴ Δ =100 × 103 × √2 × 1
2 × 0.05 × 30 × 106
=100 × 103 × √2
0.1 × 30 × 106=
√2
30
∴ Δ = 0.471
Q NO. 35.
[Ans. *] Range: 64 to 66
Shear force at section X-X Vu = 100 − 5 × 10 = 50 kN Depth at section X-X
d = 400 +200
10× 5 = 500 mm = 0.5 m
Moment at section X-X Mu = 100 × 5 − 10 × 2.5 × 5 = 375 kNm
5 m
600 m 400 m
10 kN/m
Effective span = 20 m X
β
X
.
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Design shear force at section X-X_,
Vu,design = Vu +Mu
dtan β
= 50 +375
0.5×
200
10000= 65 kN
Q NO. 36.
[Ans. *] Range: 2.9 to 3.1
BMQ = 11.25 × 150 = 1.6875 × 106N − mm
⇒σ
y=
MQ
I
Where, y =150
2= 75 mm and I =
(150)4
12
⇒ σ =1.6875 × 106 × 75
(150)4/12= 3 MPa
11.25 kN 11.25 kN
P S
Q R
11.25 kN 11.25 kN
.
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Q NO. 37.
[Ans. C]
Tensile strength of plate in arrangement (2) will be greater than in arrangement (1) ∗ As per IS code 800: 2007 close 6.3
(0.9 Anet
fup
γml)
2
> (0.9 Anet
fup
γml)
1
(Anet)2 > (Anet)1
[(B − 2d +p2
4g) t]
2
> [(B − d)t]1
B − 2d +p2
4g> B − d
p2
4g> d
p2 > 4gd
P P P P d g
p
Figure 1 Figure 2
.
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Q NO. 38.
[Ans. A] DS = 2 ∴ Number of plastic hinge required for complete collapse = DS + 1 = 2 + 1 = 3 Mechanism 1:
Δ =2L
3θ=
4L
3
⇒ θ = 2θ For principal of virtual work done
−2MPθ − 2MPθ − 2MPϕ − MPϕ = P (2L
3θ) = 0
⇒ 4MPθ + 3MPϕ =2PL
3θ
⇒ 8MPϕ + 3MPϕ =2PL
3ϕ
⇒ 11MP =4PuL
3
⇒ Pu =33
4
MP
L
∴ Pu = 8.25 MP
L
P
θ ϕ
ϕ θ
2MP MP
2MP 2MP
Δ
2L
3
4L
3
.
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Mechanism 2:
2MPθ + MPθ + MPθ + MPθ = P (2L
3)
⇒ 5MP =2PL
3
⇒ Pu =15MP
2L
∴ Pu = 7.5MP
L
Q NO. 39.
[Ans. C]
P
θ θ
θ θ
2MP MP
MP MP
.
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The critical duration is 15 days which is observed along the path P-Q-T-W-X which is the critical path of the project Note: Critical path is the one which consumes maximum amount of time
Q NO. 40.
[Ans. *] Range: 495 to 505
q =KH ⋅ Nf
Nd
K =3mm
min=
3 × 10−3m
60m/s
H = 5 m, Nf = 20, Nd = 10
q =3 × 10−3
60× 5 ×
20
10m3 sec⁄ per m length of dam
q =3 × 10−3 × 5 × 20
60 × 10× 106cm3 sec⁄ perm length of dam
q = 500 cm3/ sec per m lnegth of dam
TE = 6 TS = 7
10 20 40 50
30 70
60
80 90
TE = 0 TS = 0
TE = 2 TS = 2
P 2 4
R U 3
2
X
TE = 5 TS = 5
Q
3 5
T W
3
TE = 10 TS = 10
TE = 6 TS = 7
TE = 13 TS = 13
TE = 15 TS = 15
V
2 3
S
TE = 6 TS = 11
.
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Q NO. 41.
[Ans. *] Range: 69 to 70.5 In c‐ ϕ soil
Earth pressure pa = kaσv − 2c √ka
ka =1 − sin ϕ
1 + sin ϕ=
1 − sin 24
1 + sin 24 = 0.4217
Note: Below water table, water pressure will not be multiplied by ka at point A σy = 1 × γb + 4γsat + 3γsat
σy = 1 × γb + (4 × γ′ + 4 × γw) + (3γ′ + 3γw)
σy = (1 × γb + 4γ′ + 3γ′) + (4γw + 3γw)
Earth Pressure at ‘A’
pa = kaσv − 2c√ka
= ka[γb + 4γ′ + 3γ′] + 4γw + 3γw − 2 × c√ka
= 0.4217[16.5 + 4(19 − 9.81) + 3(18.5 − 9.81)] + 7 × 9.81 − 2 × 25 × √0.4217 pa = 69.65 kN m2⁄
Q NO. 42.
[Ans. B]
.
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OMC − SP > OMC − MP MDD − SP < MDD − MP
Q NO. 43.
[Ans. *] Range: 0.04 to 0.05
Discharge =200 ml
15 min=
200 cm3
15 × 60 sec=
200 × 103
900
mm3
sec
As per Darcy q = kavgiA
Water content
Standard
Proctor Test
Modified
Proctor Test
Dry
Den
sity
.
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kavg =ΣZi
ΣZiki
[∵ Flow is normal to bedding plane]
kavg =150 + 150
1500.02
+150
k
i =Head difference
length=
600 − 300
300= 1
A = 80 cm2 = 80 × 102 mm2
q = [150 + 150
1500.02
+150
k
] × 1 × 80 × 102 =200 × 103
900
k = 0.045 mm/ sec
Q NO. 44.
[Ans. *] Range: 298 to 299 Local shear failure is occurring hence modified c and ϕ should be used
cm =2
3c =
2
3× 35 = 23.33 kN m2⁄
tan ϕm =2
3tan ϕ
2
3tan 28.63
ϕm = 20°
.
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For ϕm = 20°, Nc = 17.7, Nq = 7.4, Nγ = 50
⇒ Water table is at Df + B = 1.5 + 4 = 5.5 m hence no effect on bearing capacity ⇒ As per Terzaghi for strip footing qu = cNc + 8DfNq + 0.5 Bγ Nγ
qu =2
3× 35 × 17.7 + 17 + 1.5 × 7.4 + 0.5 × 4 × 17 × 5
qu = 771.7 kN m2⁄ qnu = qu − γDf = 771.7 − 17 × 1.5 qnu = 746.2 kN m2⁄ Net safe bearing capacity
qns =qnu
F=
746.2
2.5= 298.48 kN m2⁄
Q NO. 45.
[Ans. *] Range: 7.4 to 8.0
Force exerted by jet in x-direction
Water jet
30°
20
0 m
m
F
v
.
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Fx = m[v sin θ − 0] = ρ × q × v sin θ
= (103) |π
4(0.02)2 × 10| 10 sin 30°
= 15.7079 N Taking moment about hinge
Fx ×0.2
2= F × 0.2
F = 7.85 N
Q NO. 46.
[Ans. *] Range: 59 to 61
Time (1)
Ordinate of 1 hr UH
(𝐦𝟑 𝐬⁄ )
(2)
Offset ordinate
(𝐦𝟑 𝐬⁄ )
(3)
Ordinate of 2 hr DRH
(𝐦𝟑 𝐬⁄ )
(4) = (2) +(3)
Ordinate of DRH of 4 cm rainfall excess (𝐦𝟑 𝐬⁄ ) (𝟓)= (𝟒) × 𝟒 𝟐⁄
Ordinate of flood
hydrograph
(𝐦𝟑 𝐬⁄ ) (𝟔) = (𝟓) + 𝟐𝟎
10:00 am 11:00 am 12:00 pm 01:00 pm 2:00 pm 3:00 pm 5:00 pm
0 3
12 8 6 3 0
- 0 3
12 8 6 3
0 3
15 20 14 9 3 0
0 6
30 40 28 18 6 0
20 26 50 60 48 38 26 20
Ordinate of 01:00 pm = 60 m3 s⁄
Q NO. 47.
[Ans. *] Range: 0.19 to 0.21 The maximum jump (ΔZ) that can be provided is given by
y +Q2
2gA2= ΔZjump +
3
2yc
Here, A = 3 × 0.5 = 1.5 m2
yc = (Q2
gB2)
1 3⁄
= (62
9.81 × 32)
1 3⁄
= 0.7415 m
.
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⇒ 0.5 +62
2 × 9.81 × 1.52= ΔZjump +
3
2× 0.7415
⇒ ΔZjump = 0.20 m
Q NO. 48.
[Ans. *] Range: 6565 to 6580 Apply energy equation at the free surface of reservoir and exit of nozzle
500 = Head loss +v1
2
2g
500 = 0.05v1
2
2g+
v12
2g
√2 × 10 × 500
1.05= v1
V1 = 97.59 m sec ⁄
Water Power (W. P) =1
2mv1
2
=1
2(103) ×
π
4(0.15)2(97.59) = 8212.178 kW
Now, η0 =Shaft Power(S. P)
W. P
0.8 =Shaft Power(S. P)
8212.178
S. P = 6569.74 kW ≅ 6570 kW
Q NO. 49.
[Ans. D] Seepage velocity
Vs =v
n=
distance
time
As per Darcy, v = ki ki
n=
100 m
100 days
.
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i =head difference
length=
3
100
k × 3
0.15 × 100=
100
100m day⁄
k = 5 m day⁄
Q NO. 50.
[Ans. A] Ca2+ = 2.65 meq l⁄ , Mg2+ = 1.45 meq l⁄ Na+ = 2.25 meq l⁄ , K+ = 0.5 meq l⁄ HCO3
− = 3.3 meq l⁄ , SO42− = 0.6 meq l⁄
Cl− = 2.85 meq l⁄ Hardness is due to multivalent metallic cations, i.e. Ca2+ and Mg
2+
Total hardness (mg
las CaCO3) = (Total meq l⁄ ) × (eq. weight of CaCO3 in mg)
= (2.65 + 1.45) × 50 mg l⁄ as CaCO3 = 205 mg l⁄ as CaCO3
Alkalinity is due to the presence of HCO3− in this case
Alkalinity (mg l⁄ as CaCO3) = 3.3 × 50 mg l⁄ as CaCO3 = 165 mg l⁄ as CaCO3
Now, Carbonate Hardness = Min {Total Hardness, Alkalinity} = 165 mg/l
Non- carbonate hardness = Total hardness – carbonate hardness = 205 − 165 = 40 mg l⁄ as CaCO3
Q NO. 51.
[Ans. *] Range: 67 to 69
.
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: 080-617 66 222, [email protected] ©Copyright reserved. Web:www.thegateacademy.com 35
L2 = L1 − |20 log (R2
R1)|
= 74 − 20 log 0.5 = 67.98 dB
Q NO. 52.
[Ans. *] Range: 275 to 277 BOD5 = L0(1 − e−0.22×5) BOD3 = L0(1 − e−0.22×3) From equation ① and ②, we get BOD5
BOD3=
(1 − e−0.22×5)
(1 − e−0.22×3)
BOD5 = 200 ×0.667
0.483
= 200 × 1.38 = 276.19 mg l⁄
Q NO. 53.
[Ans. A] Y = y1 + y2 + y3 = 0.30 + 0.25 + 0.25 = 0.80 New total lost time, L = 10 sec (given) ∴Optimum cycle time,
C0 =1.5 L + 5
1 − Y
⇒ C0 =(1.5 × 10) + 5
1 − 0.80=
15 + 5
0.20=
20
20= 100 sec
Now green times are calculated by,
G1 =y1
y2
(C0 − L) =0.30
0.80(100 − 10) = 33.75 ≅ 34 sec
G2 =y2
y(C0 − L) =
0.25
0.80(100 − 10) = 28.11 ≅ 28 sec
G3 =y3
y(C0 − L) =
0.25
0.80(100 − 10) = 28.11 ≅ 28 sec
.
GATE-2016 CE-SET-2
: 080-617 66 222, [email protected] ©Copyright reserved. Web:www.thegateacademy.com 36
Q NO. 54.
[Ans. *] Range: 92 to 93
Total energy lost between point ① and ② = Work done by frictional force 1
2mv1
2 −1
2mv2
2 + mg × 0.03s = f × (mg) × s
(0.278 × 100)2
2−
(0.278 × 50)2
2+ 9.81 × 0.03 × s = 0.35 × 9.81 × s
289.815 = 3.1392 s ⇒ s = 92.32 m
Q NO. 55.
[Ans. *] Range: 120 to 121
Given, H = 700 m, havg = 250
Relief distance, d = r1 − r = 112.5 − 82.40 = 30.1 mm
∴ d =hr1
H − havg [Where h is height of tower]
⇒ 30.1 =h × 112.5
700 − 250
0.03 s
s
V1 = 100 km hr⁄
V2 = 50 km hr⁄
①
②
r
H
r1
havg
h
.
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: 080-617 66 222, [email protected] ©Copyright reserved. Web:www.thegateacademy.com 37
∴ h = 120.4 mm