GATE 2007 Civil Engineering Question
Paper
Q.1 - Q.20
Carry One Mark Each.
1. The minimum and the maximum eigen velue of
the matrix are
-2 and 6, respectively. What is the other eigen value ?
(a) 5 (b) 3 (c) 1 (d) -1
2. The degree of the differential equation is
(a) 0 (b) 1 (c) 2 (d) 3
3. The solution for the differential equation =
x2y with
the condition that y = 1 at x = 0 is
(A) y = (B) ln(y) = (C) ln(y) = (D) y =
4. An axially loaded bar is subjected to a
normal stress of 173 MPa. The shear stress in the bar is
(a) 75 MPa (b) 86.5
MPa (c) 100 MPa (d) 122.3 MPa
5. A steel column, pinned at both ends, has a
buckling load of 200kN. If the column is restrained against lateral movement at
its mid-height, its buckling load will be
(A) 200kN (B) 283kN
(C) 400kN (D) 800kN
6. The stiffness coefficient kij indicates
(a) force at i due to a unit
deformation at j
(b) deformation at j due to a unit
force at i
(c) deformation at i due to a unit
force j
(s) force at j due to a unit
deformation i
7. For an isotropic material, the relationship
between the Young's modulus (E), shear modulus (G) and Poisson's ratio (m) is given by
(A) G = (B)
(C) G = (D) G
=
8. A clay soil sample is tested in a triaxial
apparatus in consolidated-drained conditions at a cell pressure of 100 kN/m2. What will be the pore water pressure
at a deviator stress of 40 kN/m2 ?
(a) 0 kN/m2 (b) 20 kN/m2 (c) 40 kN/m2 (d) 60 kN/m2
9. The number of blows observed in a Standard
Penetration Test (SPT) for different penetration depths are given as follows
Penetration of sampler |
Number of blows |
0-150 mm |
6 |
150-300 |
8 |
300-450 mm |
10 |
The observed N value is
(a) 8 (b) 14 (c) 18 (d) 24
10. The vertical stress at some depth below the
corner of a 2m x 3m rectangular footing due to a certain load intensity is 100
kN/m2. What will be the
vertical stress in kN/m2 below
the centre of a 4m x 6m rectangular footing at the same depth and same load
intensity?
(a) 25 (b) 100 (c) 200 (d) 400
11. There is a free overfall at the end of a long
open channel. For a given flow rate, the critical depth is less than the normal
depth. What gradually varied flow profile will occur in the channel for this
flow rate ?
(a) M1 (b) M2 (c) M3 (d) S1
12. The consumptive use of water for a crop
during a particular stage of growth is 2.0 mm/day. The maximum depth of
available water in the root zone is 60 mm. Irrigation is required when the
amount of available water in the root zone. Frequency of irrigation should be
(a) 10 days
(b) 15 days (c) 20
days (d) 25 days
13. As per the Lacey's method for design of a
alluvail channels, identify the true statement from the following
(a) Wetted perimeter increases with
an increase in design discharge
(b) Hydraulic radius increases with
an increase in silt factor.
(c) Wetted perimeter decreases with
an increase in design discharge.
(d) Wetted perimeter increases with
an increase in silt factor
14. At two points 1 and 2 in a pipeline the
velocities and V and 2V, respectively. Both the points are at the same
elevation. The fluid density is r. The
flow can be assumed to be in compressible, inviscid, steady and irrotational.
The difference in pressures P1 and
P2 at points at 1 and 2
is
(a) 0.5 rV2 (b) 1.5
rV2 (c) 2rV2 (d) 3
rV2
15. The presence of hardness in excess of
permissible limit causes
(a) cardio vascular problems
(b) skin discolouration
(c) calcium deficiency
(d) increased laundry expenses
16. The dispersion of pollutants in atmosphere is
maximum when
(a) environmental lapse rate is
greater than adiabatic lapse rate
(b) environmental lapse rate is less
than adiabatic lapse rate
(c) environmental lapse rate is equal
to adiabatic lapse rate
(d) maximum mixing depth is equal to
zero
17. The alkalinity and hardness of a water sample
are 250 mg/L and 350 mg/L as CaCO3,
respectively. The water has
(a) 350 mg/L carbonate hardness and
zero non-carbonate hardness.
(b) 250 mg/L carbonate hardness and
zero non-carbonate hardness.
(c) 250 mg/L carbonate hardness and
350 mg/L non-carbonate hardness.
(d) 250 mg/L carbonate hardness and
100 mg/L non-carbonate hardness.
18. The consistency and flow resistance of
bitumen can be determined from the following
(a) Ductitility test
(b) Penetration test
(c) Softening point test
(d) Viscosity test
19. If a two-lane national highway and a two-lane
state highway intersect at right angles, the number of potential conflict
points at the intersecton, assuming that both the roads are two-way is
(a) 11 (b) 17 (c) 24 (d) 32
20. In signal design as per Indian Roads Congress
specifications, if the sum of the ratios of normal flows to saturation flow of
two directional traffic flow is 0.50 and the total lost time per cycle is 10
seconds, the optimum cycle length in seconds is
(a) 100 (b) 80 (c) 60
(d) 40
Q. 21 to Q.75
carry two marks each :
21. For what values of α and b the following simultaneous equations have
an infinite number of solutions?
x+y+z = 5; x+3y+3z = 9;
x+2y+az = b
(a) 2,7 (b) 3,8 (c) 8,3 (d) 7,2
22. A velocity vector is given as
The divergence of this velocity vector a
(1,1,1) is
(a) 9 (b) 10 (c) 14
(d) 15
23. A body originally at 60°C cools down to 40°C in 15 minutes when kept in air at a temperature of 25°C. What will be the temperature of the body
at the end of 30 minutes ?
(a) 35.2°C (b) 31.5°C (c) 28.7°C (d) 15°C
24. The following equation needs to be
numerically solved using the Newton-Raphson method.
x3+4x-9
= 0
The iterative equation for this purpose is
(k indicates the iteration level)
(A) (B)
(C) (D)
25. Evaluate
(a) p (b) p/2 (c) p/4 (d) p/3
26. Potential function f is given as f = x2 + y2.
What will be the stream function (ψ) with the condition ψ = 0 at x =
y = 0 ?
(a) 2xy (b) x2 + y2 (c) x2 - y2 (d) 2x2 y2
27. The inverse of the 2 ´ 2 matrix is
(A) (B) (C) (D)
28. Given that one root of the equation x3 -10x2 + 31x - 30 = 0 is 5, the other two roots are
(a) 2 and 3 (b) 2
and 4 (c) 3 and 4 (d) -2 and -3
29. If the standard
deviation of the spot speed of vehicles in a highway is 8.8 kmph and the mean
speed of the vehicles is 33 kmph, the coefficient of variation in speed is
(a) 0.1517 (b) 0.1867 (c) 0.2666 (d) 0.3646
30. A metal bar of
length 100 mm is inserted between two rigid supports and its temperature is
increased by 10°C. If the coefficient
of thermal expansion is 12 ´ 10-6 per °C and the young's modulus is 2 × 105 MPa, the stress in the bar is
(a) zero (b) 12
MPa (c) 24 MPa (d) 2400 MPa
31. A rigid bar is
suspended by three rods made of the same material as shown in the figure. The
area and length of the central rod are 3A and L, respectively while that of the
two outer rods are 2A and 2L, respectively. If a downward force of 50 kN is
applied to the rigid bar, the forces in the central and each of the outer rods
will be
(a) 16.67
kN each (b) 30 kN and 15 kN
(c) 30 kN and 10 kN
(d) 21.4 kN and 14.3 kN
32. The maximum and
minimum shear stresses in a hollow circular shaft of outer diameter 20 mm and
thickness 2mm, subjected to a torque of 92.7 N.m will be
(a) 59
MPa and 47.2 MPa (b) 100 MPa and 80 MPa
(c) 118 MPa and 160 MPa (d) 200
MPa and 160 MPa
33. The shear stress
at the neutral axis in a beam of triangular section with a base of 40 mm and
height 20 mm, subjected to a shear force of 3 kN is
(a) 3 MPa
(b) 6 MPa (c) 10
MPa (d) 20 MPa
34. U1 and U2 are the strain energies stored in a prismatic bar
due to axial tensile forces P1 and
P2, respectively. The strain
energy U stored in the same bar due to combined action of P1 and P2 will be.
(a) U = U1 + U2 (b) U
= U1U2 (c) U < U1
+ U2 (d) U > V1 + U2
35. The right
triangular truss is made of members having equal cross sectional area of 1550
mm2 and Young's modulus
of 2 ´ 105 MPa. The horizontal deflection of the joint Q is
(a) 2.47 mm (b) 10.25
mm (c) 14.31 mm (d) 15.68 mm
36. The influence line diagram (ILD) shown is for
the member
(a) PS (b) RS (c) PQ (d) QS
37. Consider the
following statements :
I. The compressive
strength of concrete decreases with increase in water-cement ratio of the
concrete mix.
II. Water
is added to the concrete mix for hydration of cement and workability.
III. Creep and
shrinkage of concrete are independent of the water-cement ratio in the concrete
mix.
The true
statements are
(a) I and II (b) I,
II and III (c) II and III (d) only II
38. The percentage
loss of prestress due to anchorage slip of 3 mm in a concrete beam of length 30
m which is post-tensioned by a tendon with an initial stress of 1200 N/mm2 and modulus of elasticity equal to
2.1 x 105 N/mm2 is
(a) 0.0175 (b) 0.175 (c) 1.75
(d) 17.5
39. A concrete beam
of rectangular cross-section of size 120 mm (width) and 200 mm (depth) is
prestressed by a straight tendon to an effective force of 150 kN at an
eccentricity of 20 mm (below the centroidal axis in the depth direction). The
stresses at the top and bottom fibres of the section are
(a) 2.5
N/mm2 (compression), 10N/mm2 (compression), 10N/mm2 (compression).
(b)
10N/mm2 (tension), 2.5 N/mm2 (compression)
(c)
3.75 N/mm2 (tension), 3.75 N/mm2 (compression)
(d) 2.75 N/mm2 (compression),
3.75 N/mm2 (compression)
40. Consider the
following statements :
I. Modulus
of elasticity of concrete increases with increase in compressive strength of
concrete.
II. Brittleness
of concrete increases with decrease in compressive strength of concrete.
III. Shear
strength of concrete increases with increase in compressive strength of
concrete.
The TRUE statements
are
(a) II and III (b) I,
II and III (c) I and II (d) I and III
41. A steel flat of
rectangular section of size 70 ´ 6 mm
is connected to a gusset plate by three bolts each having a shear capacity of
15 kN in holes having diameter 11.5 mm. If the allowable tensile stress in the
flat is 150 MPa, the maximum tension that can be applied to the flat is
(a) 42.3
kN
(b) 52.65 kN
(c) 59.5 kN
(d) 63.0 kN
42. A bracket connection is made with four bolts
of 10 mm diameter and supports a load of 10 kN at an eccentricity of 100 m. The
maximum force to be resisted by any bolt will be
(a) 5 kN (b) 6.5
kN (c) 6.8 kN (d) 7.16 kN
43. The
plastic collapse load Wp for
the propped cantilever supporting two point loads as shown in figure terms of
plastic moment capacity, Mp is
given by
(a) 3 Mp/L (b) 4MP/L
(c) 4MP/L (d) 6MP/L
44. Sieve analysis on
a dry soil sample of mass 1000 g showed that 980 g and 270 g of soil pass
through 4.75 mm and 0.075 mm sieve, respectively. The liquid limit and plastic
limits of the soil fraction passing through 425m
sieves are 40% and 18% respectively. The soil may be classified as
(a) SC
(b) MI (c) CI (d)
SM
45. The water content
of a saturated soil and the specific gravity of soil solids were found to be 30%
and 2.70, respectively. Assuming the unit weight of water to be 10 kN/m3, the saturated unit weight (kN/m3) and the void ratio of the soil are
(a) 19.4, 0.81 (b) 18.5,
0.30 (c) 19.4, 0.45 (d) 18.5, 0.45
46. The factor of safety of an infinite soil
slope shown in the figure having the properties
c = 0, c = 0, f
= 350, gdry =
16 kN/m3
and gsat = 20 kN/m3 is approximately equal to
(a) 0.70 (b) 0.80 (c) 1.00 (d)
1.20
47. Match the
following groups
Group = I
Group - II
P Constant head permeability test 1.
Pile foundations
Q Consolidation test
2. Specific
gravity
R Pycnometer test
3. Clay
soil
S Negative
skin friction 4. Sand
(a) P-4, Q-3, R-2, S-1
(b) P-4, Q-2, R-3, S-1
(c) P-3, Q-4, R-2- S-1
(d) P-4, Q-1, R-2, S-3
48. The bearing capacity of a rectangular footing
of plan dimensions 1.5 m x 3m resting on the surface of a sand deposit was
estimated s 600 kN/m2 of
a sand deposit was estimated as 600 kN/m2 when
the water table is far below the base of the footing. The bearing capacities in
kN/m2 when the water
level rises to depths of 3m, 1.5 m and 0.5 m below the base of the footing are
(a) 600, 600, 400 (b) 600,
450, 350 (c) 600, 500, 250 (d) 600, 400, 250
49. What is the ultimate capacity in kN of the
pile group sown in the figure assuming the group to fail as a single block ?
(a) 921.6 (b) 1177.6 (c) 2438.6 (d) 3481.6
50. A horizontal
water jet with a velocity of 10 m/s and cross sectional area of 10 mm2strikes a flat plate held normal to the
flow direction. The density of water is 1000 kg/m3. The total force on the
plate due to the jet is
(a) 100 N (b) 10
N (c) 1 N (d) 0.1 N
51. A 1: 50scale
model of a spillway is to be tested in the laboratory. The discharge in the
prototype is 1000 M3/s. The
discharge to be maintained in the model test is
(a) 0.057 m3/s (b) 0.08m2/s (c) 0.57 m3/s (d) 5.7 m3/s
52. A triangular open
channel has a vertex angle to 90° and
carries flow at a critical depth of 0.30 m. The discharge in the channel is
(a) 0.08 m3/s (b) 0.11 m3/s (c) 0.15 m3/s (d) 0.2 m3/s
53. Flow rate of a
fluid (density = 1000 kg/m3)
in a small diameter tube is 800 mm3/s.
The length and the diameter of the tube are 2 m and 0.5 mm, respectively. The
pressure drop in 2 m length is equal to 2.0 MPa. The viscosity of the fluid is
(a) 0.025 N.s/m2 (b) 0.012 N.s/m2 (c) 0.00192 N.s/m2 (d) 0.00102 N.s/m2
54. The flow rate in
a wide rectangular open channel is 2.0 m3/s
per metre width. The channel bed slope is 0.002. The Manning's roughness
coefficient is 0.012. The slope of the channel is classified as
(a) Critical (b) Horizontal (c) Mild
(d) Steep
55. The culturable
command area for a distributary channel is 20,000 hectares. Wheat is grown in
the entire area and the intensity of irrigation is 50%. The kor period for
wheat is 30 days and the kor water depth is 120 mm. The outlet discharge for
the distributary should be
(a) 2.85 m3/s (b) 3.21 m3/s (c) 4.63 m3/s (d) 5.23 m3/s
56. An isolated
4-hour storm occurred over a catchment as follows
Time |
1st hour |
2nd hour |
3rd hour |
4th hour |
Rainfall (mm) |
9 |
28 |
12 |
7 |
The f index for the catchment is 10 mm/h. The
estimated runoff depth from the catchment due to the above storm is
(a) 10 mm (b) 16
mm (c) 20 mm (d) 23 mm
57. Two electrostatic
precipitators (ESPs) are in series. The fractional efficiencies of the upstream
and downstream ESPs for size dp are
80% and 65%, respectively. What is the overall efficiency of the system for the
same dp?
(a) 100% (b) 93% (c) 80% (d) 65%
58. 50 g of CO2 and 25 g of CH4 are produced from the
decomposition of municipal solid waste (MSW) with a formula weight of 120 g.
What is the average per capita green house gas production in a city of 1
million people with a MSW production rate of 500 ton/day ?
(a) 104 g/day (b) 120
g/day (c) 208 g/day (d) 313 g/day
59. The extra widening required for a two-lane
national highway at a horizontal curve of 300 m radius, considering a wheel
base of 8 m and a design speed of 100 kmph is
(a) 0.42 m (b) 0.62
m (c) 0.82 m (d) 0.92 m
60. While designing a hill road with a ruling
gradient of 6%, if a sharp horizontal curve of 50 m radius is encountered, the
compensated gradient at the curve as per the Indian Roads Congress
specifications should be
(a) 4.4% (b) 4.75% (c) 5.0% (d) 5.25%
61. The design speed on a road is 60 kmph.
Assuming the driver reaction time of 2.5 seconds and coefficient of friction of
pavement surface as 0.35, the required slopping distance for two-way traffic on
a single lane road is
(a) 82.1 m (b) 102.4
m (c) 164.2 m (d) 186.4 m
62. The width of the expansion joint is 20 mm in
a cement concrete pavement. The laying temperature is 20°C and the maximum slab temperature in summer is 60°C. The coefficient of thermal expansion of
concrete is 10×10-6 mm/mm/oC and the joint filler compresses up to
50% of the thickness. The spacing between expansion joints should be
(a) 20 m (b) 25
m (c) 30 m (d) 40 m
63. The following data pertains to the number of
commercial vehicles per day for the design of a flexible pavement for a
national highway as per IRC:37-1984
Type of commercial Number of vehicles per
day
Vehicle Damage Factor
Vehicle considering the number f lanes
Two axle trucks
2000 5
Tandem axle trucks
200 6
Assuming a traffic growth factor of 7.5% per
annum for both the types of vehicles, the cumulative number of standard axle
load repetitions (in million) for a design life of ten years is
(a) 44.6 (b) 57.8 (c) 62.4 (d) 78.7
64. Match the following tests on aggregate and
its properties
TEST
PROPERTY
P. Crushing test 1.
Hardness
Q. Los Angeles abrasion test 2. Weathering
R. Soundness test 3. Shape
S. Angularity test 4. Strength
(a) P-2, Q-1, R-4, S-3 (b) P-4,
Q-2, R-3, S-1
(c) P-3, Q-2, R-1, S-4 (d) P-4,
Q-1, R-2, S-2
65. The plan of a map was photo copied to a
reduced size such that a line originally 100 mm, measures 90 mm. The original
scale of the plan was 1 : 1000. The revised scale is
(a) 1 : 900 (b) 1
: 111 (c) 1 : 1121 (d) 1: 1221
66. The following
table gives data of consecutive co-ordinates in respect of a closed theodolite
traverse PQRSP.
Station |
Northing, m |
Southing, m |
Easting, m |
Westing, m |
P |
400.75 |
|
|
300.5 |
Q |
100.25 |
|
199.25 |
|
R |
|
199.0 |
399.75 |
|
S |
|
300.0 |
|
200.5 |
The magnitude
and direction of error of closure in whole circle bearing are
(a) 2.0 m and 45° (b) 2.0
m and 315°
(c) 2.82 m and 315° (d) 3.42
m and 45°
67. The following
measurements were made during testing a leveling instrument.
Instrument at |
Staff Reading
at |
P1 |
Q1 |
P |
2.800 m |
1.700 m |
Q |
2.700 m |
1.800 m |
P1 is close to P and Q1 is close to Q. If the reduced
level of station P is 100.000 m, the reduced level of station Q is
(a) 99.000 m (b) 100.000
m (c) 101.000 m (d) 102.000 m
68. Two straight
lines intersect at an angle of 60°. The
radius of a curve joining the two straight lines is 600m. The length of long
chord and mid-ordinates in metres of the curve are
(a) 8.4, 600.0 (b) 600.0,
80.4 (c) 600.0, 39.89 (d) 40,89, 300
69. The magnetic
bearing of a line AB is S 45° E
and the declination is 5° West.
The true bearing of the line AB is
(a) S 45° E (b) S 40° E (c) S 50° E (d) S 50° W
COMMON DATA
QUESTIONS
Common
Data for Questions 70,71
Water is flowing
through the permeability apparatus as shown in the figure. The coefficient of
permeability of the soil is k m/s and the porosity of the soil sample is 0.50.
70. The total head, elevation head and pressure
head in metres of water at the point R shown in the figure are
(a) 0.8, 0.4, 0.4
(b) 1.2, 0.4, 0.8 (c) 0.4,
0, 0.4 (d) 1.6, 0.4, 1.2
71. What are discharge velocity and seepage
velocity through the soil sample ?
(A) k, 2k (B) 2/3k,
4/3k (C) 2k,k (D) 4/3k, 2/3k
Common Data
for Questions 72 and 73 :
Ordinates of a
1-hour unit hydrograph at 1 hour intervals, starting from time t = 0, are 0, 2,
6, 4, 2, 1 and 0 m3/s.
72. Catchment area represented by this unit
hydrograph is
(a) 1.0 km2 (b) 2.0
km2 (c) 3.2
km2 (d) 5.4
km2
73. Ordinate of a 3-hour unit hydrograph for the
catchment at t= 3 hours is
(a) 2.0 m3/s (b) 3.0 m3/s (c) 4.0 m3/s (d) 5.0 m3/s
Common Data
for Questions 74 and 75 :
A completely
mixed activated sludge process is used to treat a wastewater flow of 1 million
litres per day (1 MLD) having a BOD5 of
200 mg/L. The biomass concentration in the aeration tank is 2000 mg/L and the
concentration of the net biomass leaving the system is 50 mg/L. The aeration
tank has a volume of 200 m3.
74. What is the hydraulic retention time of the
wastewater in aeration tank ?
(a) 0.2 h (b) 4.8
h (c) 10 h (d) 24 h
75. What is the average time for which the
biomass stays in the system ?
(a) 5 h (b) 8
h (c) 2 days (d) 8 days
Linked Answer
questions : Q.76 to Q.85 carry two marks each.
Statement of
Linked Answer Questions 76 and 77.
A two span
continuous beam having equal spans each of length L is subjected to a uniformly
distributed load w per unit length. The beam has constant flexural rigidly.
76. The reaction at the middle support is
(a) wL (b) (c) (d)
77. The bending moment at
the middle support is
(a) 4wL2 (b)
8wL2 (c) 12wL2 (d) 16wL2
Statement for
Linked Answer Questions 78 and 79
A singly
reinforced rectangular concrete beam has a width of 150 mm and an effective
depth of 330 mm. The characteristics compressive strength of concrete is 20 MPa
and the characteristics tensile strength of steel is 415 MPa. Adopt the stress
block for concrete as given in IS 456-2000 and take limiting value of depth of
neutral axis as 0.48 times the effective depth of the beam.
78. The limiting value of the moment of resistance
of the beam is kN.m is
(A) 0.14 (B) 0.45
(C) 45.08 (D) 156.82
79 The limiting area of tension steel in mm2 is
(A) 473.9 (B) 412.3
(C) 373.9 (D) 312.3
Statement for
Linked Answer Questions 80 and 81
The ground
conditions at a site are as shown in the figure. The water table at the site
which was initially at a depth of 5m below the ground level got permanently
lowered to a depth of 15m below the ground level due to pumping of water over a
few years. Assume the following data
i. unit weight of water = 10kN/m3
ii. unit weight of sand above water table =
18kN/m3
iii. unit weight of sand and clay below the
water table = 20kN/m3
iv. coefficient of volume compressibility =
0.25m2/MN
80. What is the change in the effective stress in
kN/m2 at mid-depth of the clay layer due to the lowering of the water table?
(A) 0 (B) 20 (C) 80
(D) 100
81. What is the compression of the clay layer in
mm due to the lowering of the water table?
(A) 125 (B) 100
(C) 25 (D) 0
Statement for Linked
Answer Questions 82 and 83
A rectangular
open channel needs to be designed to carry a flow of 2.0 m3/s under uniform flow conditions. The
Manning's roughness coefficient is 0.018. The channel should be such that the
flow depth is equal to half the width, and the Froude number is equal to 0.5
82. The bed slope of the channel to be provided
is
(a) 0.0012 (b) 0.0021 (c) 0.0025 (d) 0.0052
83. Keeping the width, flow depth and roughness
the same, if the bed slope of the above channel is doubled, the average,
boundary shear stress under uniform flow conditions is
(a) 5.6 N/m2 (b) 10.8 N/m2 (c) 12.3 N/m2 (d) 17.2 N/m2
Statement for
Linked Answer Questions 84 and 85
A plain
sedimentation tank with a length of 20m, width of 10 m, and a depth of 3 m is
used in a water treatment plant to treat 4 million litres of water per day (4
MLD). The average temperature of water is 20°C.
The dynamic viscosity of water is 1.002 x 10-3 N.s/m2 at 20°C. Density of water is 998.2 kg/M3. Average specific gravity of particles is 2.65.
84. What is the surface overflow rate in the
sedimentation tank ?
(a) 20 m3/m2/day
(b) 40
m3/m2/day
(c) 67 m3/m2 day
(d) 133
m3/m2/day
85. What is the minimum diameter of the particle
which can be removed with 100% efficiency in the above sedimentation tank?
(a) 11.8 ´ 10-3 mm
(b) 16.0
´ 10-3 mm
(c) 50 ´
10-3 (d) 160
´ 10-3 mm
End of Question Paper