Rapid gravity filters (A) Were developed by G.W. Fuller (B) Make use of coarser sand with effective size as 0.5 mm (C) Yield as high as 30 times the yield of slow sand filters (D) All the above

Rapid gravity filters 

(A) Were developed by G.W. Fuller 

(B) Make use of coarser sand with effective size as 0.5 mm 

(C) Yield as high as 30 times the yield of slow sand filters 

(D) All the above 

by

1 Answer

Answer :

(D) All the above 

by

Related questions

The yield of a rapid gravity filter as compared to that of slow sand filter, is (A) 10 times (B) 15 times (C) 20 times (D) 30 times

Description : The yield of a rapid gravity filter as compared to that of slow sand filter, is (A) 10 times (B) 15 times (C) 20 times (D) 30 times

Last Answer : (D) 30 times

A high velocity of wash water is required for (A) Rapid gravity filter with strainers (B) Rapid gravity filter without strainers (C) Slow sand filter with strainers (D) Slow sand filter without strainers

Description : A high velocity of wash water is required for (A) Rapid gravity filter with strainers (B) Rapid gravity filter without strainers (C) Slow sand filter with strainers (D) Slow sand filter without strainers

Last Answer : (B) Rapid gravity filter without strainers

Pick up the incorrect statement from the following: (A) The water entering the slow sand filters should be treated by 9.386 coagulants (B) The depth of water on the filter should be twice the depth of the filter sand (C) When the filter head is 0.75 times the depth of filter sand, the water obtained is purest (D) All the above

Description : Pick up the incorrect statement from the following:  (A) The water entering the slow sand filters should be treated by 9.386 coagulants  (B) The depth of water on the filter should be twice the ... is 0.75 times the depth of filter sand, the water obtained is purest  (D) All the above 

Last Answer : (D) All the above 

Distribution of wash water is provided in (A) Sedimentation tank (B) Slow sand filter (C) Rapid gravity filter (D) All the above

Description : Distribution of wash water is provided in  (A) Sedimentation tank  (B) Slow sand filter  (C) Rapid gravity filter  (D) All the above 

Last Answer : (C) Rapid gravity filter

In rapid sand filters the ratio of length and diameter of the lateral, should not be greater than (A) 10 (B) 15 (C) 20 (D) 25

Description : In rapid sand filters the ratio of length and diameter of the lateral, should not be greater than (A) 10 (B) 15 (C) 20 (D) 25

Last Answer : (C) 20

Rapid hardening cement attains early strength due to (A) Larger proportion of lime grounded finer than normal cement (B) Lesser proportion of lime grounded coarser than normal cement (C) Lesser proportion of lime grounded finer than normal cement (D) Excess percentage of gypsum

Description : Rapid hardening cement attains early strength due to (A) Larger proportion of lime grounded finer than normal cement (B) Lesser proportion of lime grounded coarser than normal cement (C) Lesser proportion of lime grounded finer than normal cement (D) Excess percentage of gypsum

Last Answer : Answer: Option A

Rapid gravity filters can remove bacterial impurities up to a maximum of (A) 50 % (B) 60 % (C) 70 % (D) 80 %

Description : Rapid gravity filters can remove bacterial impurities up to a maximum of  (A) 50 %  (B) 60 %  (C) 70 %  (D) 80 %

Last Answer : (D) 80 %

The admixture of coarser particles like sand or silt to clay causes (A) Decrease in liquid limit and increase in plasticity index (B) Decrease in liquid limit and no change in plasticity index (C) Decrease in both liquid limit and plasticity index (D) Increase in both liquid limit and plasticity index

Description : The admixture of coarser particles like sand or silt to clay causes (A) Decrease in liquid limit and increase in plasticity index (B) Decrease in liquid limit and no change in plasticity index ... in both liquid limit and plasticity index (D) Increase in both liquid limit and plasticity index

Last Answer : Answer: Option C

In slow sand filters, the turbidity of raw water can be removed only up to (A) 60 mg/litre (B) 75 mg/litre (C) 100 gm/litre (D) 150 mg/litre

Description : In slow sand filters, the turbidity of raw water can be removed only up to  (A) 60 mg/litre  (B) 75 mg/litre  (C) 100 gm/litre  (D) 150 mg/litre 

Last Answer : (A) 60 mg/litre 

The bed slope in slow sand filters, is generally kept (A) 1 in 50 (B) 1 in 75 (C) 1 in 100 (D) 1 : 200

Description : The bed slope in slow sand filters, is generally kept  (A) 1 in 50  (B) 1 in 75  (C) 1 in 100  (D) 1 : 200

Last Answer : (C) 1 in 100 

A sewer pipe contains 1 mm sand particles of specific gravity 2.65 and 5 mm organic particles of specific gravity 1.2, the minimum velocity required for removing the sewerage, is A. 0.30 m/sec B. 0.35 m/sec C. 0.40 m/sec D. 0.45 m/sec

Description : A sewer pipe contains 1 mm sand particles of specific gravity 2.65 and 5 mm organic particles of specific gravity 1.2, the minimum velocity required for removing the sewerage, is A. 0.30 m/sec B. 0.35 m/sec C. 0.40 m/sec D. 0.45 m/sec

Last Answer : ANS: D

Rapid sand filter (A) Should be preceded by coagulation and sedimentation (B) Uses rapid sand as filter media(C) Is used after slow sand filtering has been done (D) Can combine disinfection also

Description : Rapid sand filter (A) Should be preceded by coagulation and sedimentation (B) Uses rapid sand as filter media (C) Is used after slow sand filtering has been done (D) Can combine disinfection also

Last Answer : (A) Should be preceded by coagulation and sedimentation

Pick out the true statement pertaining to water treatment. (A) Slow sand filters can remove colour completely (B) Activated carbon can be used for taste & odour control without subsequent filtration (C) Application of activated carbon reduces the temporary hardness of water (D) Normally, the turbidity is removed by adding a coagulant prior to sedimentation

Description : Pick out the true statement pertaining to water treatment. (A) Slow sand filters can remove colour completely (B) Activated carbon can be used for taste & odour control without subsequent filtration ... of water (D) Normally, the turbidity is removed by adding a coagulant prior to sedimentation

Last Answer : (D) Normally, the turbidity is removed by adding a coagulant prior to sedimentation

An ideal sand for filters should be (A) Free from dirt and other impurities (B) Uniform in nature and size (C) Hard and resistant (D) All the above

Description : An ideal sand for filters should be (A) Free from dirt and other impurities (B) Uniform in nature and size (C) Hard and resistant (D) All the above

Last Answer : (D) All the above

The risk of segregation is more for (A) Wetter mix (B) Larger proportion of maximum size aggregate (C) Coarser grading (D) All the above

Description : The risk of segregation is more for (A) Wetter mix (B) Larger proportion of maximum size aggregate (C) Coarser grading (D) All the above

Last Answer : Answer: Option D

Particles of 0.002 mm size are that of (A) Clay (B) Sand (C) Gravel (D) None of these

Description : Particles of 0.002 mm size are that of (A) Clay (B) Sand (C) Gravel (D) None of these

Last Answer : Answer: Option A

The weight of a pycnometer containing 400 g sand and water full to the top is 2150 g. The weight of pycnometer full of clean water is 1950 g. If specific gravity of the soil is 2.5, the water content is (A) 5 % (B) 10 % (C) 15 % (D) 20 %

Description : The weight of a pycnometer containing 400 g sand and water full to the top is 2150 g. The weight of pycnometer full of clean water is 1950 g. If specific gravity of the soil is 2.5, the water content is (A) 5 % (B) 10 % (C) 15 % (D) 20 %

Last Answer : (D) 20 %

Rapid gravity filter can only remove turbidity of water upto (A) 15 to 25 gm/litre (B) 25 to 30 gm/litre (C) 30 to 35 cm/litre (D) 35 to 40 gm/litre

Description : Rapid gravity filter can only remove turbidity of water upto (A) 15 to 25 gm/litre (B) 25 to 30 gm/litre (C) 30 to 35 cm/litre (D) 35 to 40 gm/litre

Last Answer : (D) 35 to 40 gm/litre

If is specific gravity of sand particles, is porosity, the critically hydraulic gradient (A) ic = (G + 1)/(1 - e) (B) ic = (G + 1)/(1 + e) (C) ic = (G - 1)/(1 + e) (D) ic = (G - 1)/(1 - e)

Description : If is specific gravity of sand particles, is porosity, the critically hydraulic gradient (A) ic = (G + 1)/(1 - e) (B) ic = (G + 1)/(1 + e) (C) ic = (G - 1)/(1 + e) (D) ic = (G - 1)/(1 - e)

Last Answer : Answer: Option C

Slow sand filter is used if maximum turbidity of raw water is less than (A) 10 gm/litre (B) 20 gm/litre (C) 30 gm/litre (D) 50 gm/litre

Description : Slow sand filter is used if maximum turbidity of raw water is less than (A) 10 gm/litre (B) 20 gm/litre (C) 30 gm/litre (D) 50 gm/litre

Last Answer : (D) 50 gm/litre

For grinding of softer materials, the grinding wheel should have __________ grain size. (A) Finer (B) Coarser (C) Medium (D) Any type of

Description : For grinding of softer materials, the grinding wheel should have __________ grain size. (A) Finer (B) Coarser (C) Medium (D) Any type of

Last Answer : (B) Coarser

As the product becomes finer, the energy required for grinding (A) Decreases (B) Increases (C) Is same as for coarser grinding (D) Is 1.5 times that for coarser grinding

Description : As the product becomes finer, the energy required for grinding (A) Decreases (B) Increases (C) Is same as for coarser grinding (D) Is 1.5 times that for coarser grinding

Last Answer : (B) Increases

Pick up the correct statement from the following: (A) High percentage of C3S and low percentage of C2S cause rapid hardening (B) High percentage of C3S and low percentage of C2S make the cement less resistive to chemical attack (C) Low percentage of C3S and high percentage of C2S contribute to slow hardening (D) All the above

Description : Pick up the correct statement from the following: (A) High percentage of C3S and low percentage of C2S cause rapid hardening (B) High percentage of C3S and low percentage of C2S make the cement ... ) Low percentage of C3S and high percentage of C2S contribute to slow hardening (D) All the above

Last Answer : Answer: Option D

If the viscosity of ground water is 1.00, the Slitcher's constant is 400, the effective size of soil particles in aquifer is 0.5 mm and hydraulic gradient is 1 in 80, the velocity of flow is (A) 0.25 m/day (B) 0.50 m/day (C) 1.00 m/day (D) 1.25 m/day

Description : If the viscosity of ground water is 1.00, the Slitcher's constant is 400, the effective size of soil particles in aquifer is 0.5 mm and hydraulic gradient is 1 in 80, the velocity of flow is (A) 0.25 m/day (B) 0.50 m/day (C) 1.00 m/day (D) 1.25 m/day

Last Answer : Answer: Option D

A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle system (in SI units) is given below : Δ P/L = 375 × 10 3 VOM + 10.94 × 10 6 V2 OM (SI units) If water is to be used as the fluidising medium, the minimum fluidisation velocity, VOM is (A) 12 mm/s (B) 16 mm/s (C) 24 mm/s (D) 28 mm/s

Description : A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle ... fluidisation velocity, VOM is (A) 12 mm/s (B) 16 mm/s (C) 24 mm/s (D) 28 mm/s

Last Answer : (B) 16 mm/s

Consider the following statements. The role of the gravel bed in a rapid sand filter is : 1. To filter out large suspended matter 2. To support the sand bed above it 3. To prevent the escape of sand particles 4. To uniformly distribute the backwash water 5. To prevent algae growth Which of the following statements are correct ? a) 1, 2, 3, 4 and 5 b) 2, 3 and 4 only c) 3, 4 and 5 only d) 1, 2 and 3 only

Description : Consider the following statements. The role of the gravel bed in a rapid sand filter is : 1. To filter out large suspended matter 2. To support the sand bed above it 3. To prevent the escape of sand particles 4. To uniformly ... and 5 b) 2, 3 and 4 only c) 3, 4 and 5 only d) 1, 2 and 3 only

Last Answer : b) 2, 3 and 4 only

Surface preparation for Metallising the abrasives used for final cleaning is a) Chilled iron grit G.24, as defined in BS : 2451 b) Washed salt free angular silica sand of mesh size 12 to 30 with a minimum of 40% retained on a 20 mesh c) either (a) or (b) * d) d) neither (a) or (b)

Description : Surface preparation for Metallising the abrasives used for final cleaning is a) Chilled iron grit G.24, as defined in BS : 2451 b) Washed salt free angular silica sand of mesh size 12 to 30 with a minimum of 40% retained on a 20 mesh c) either (a) or (b) * d) d) neither (a) or (b)

Last Answer : c) either (a) or (b) *

The maximum permitted loss of head in a rapid sand filter, is (A) 1 m (B) 2 m (C) 3 m (D) 4 m

Description : The maximum permitted loss of head in a rapid sand filter, is (A) 1 m (B) 2 m (C) 3 m (D) 4 m

Last Answer : (C) 3 m

In a rapid sand filter, air binding is caused due to excessive (A) Negative pressure (B) Pressure (C) Turbidity (D) Water pressure

Description : In a rapid sand filter, air binding is caused due to excessive  (A) Negative pressure  (B) Pressure  (C) Turbidity  (D) Water pressure

Last Answer : (A) Negative pressure

Firewall as part of a router program a. filters only packets coming from internet b. filters only packets going to internet c. filters packets travelling from and to the intranet from the internet d. ensures rapid traffic of packets for speedy e-Commerce

Description : Firewall as part of a router program a. filters only packets coming from internet b. filters only packets going to internet c. filters packets travelling from and to the intranet from the internet d. ensures rapid traffic of packets for speedy e-Commerce

Last Answer : c. filters packets travelling from and to the intranet from the internet 

Filters with the ___ characteristic are useful when a rapid roll-off is required because it provides a roll-off rate...

Description : Filters with the ___ characteristic are useful when a rapid roll-off is required because it provides a roll-off rate greater than –20/dB/decade/pole:  (1) Butterworth (2) Chebyshev (3) Bessel (4) Elliptical 

Last Answer : Filters with the Chebyshev characteristic are useful when a rapid roll-off is required because it provides a roll-off rate greater than –20/dB/decade/pole.

The hydraulic head that would produce a quick condition in a sand stratum of thickness 1.5 m, specific gravity 2.67 and voids ratio 0.67 is equal to(A) 1.0 m (B) 1.5 m (C) 2.0 m (D) 3 m

Description : The hydraulic head that would produce a quick condition in a sand stratum of thickness 1.5 m, specific gravity 2.67 and voids ratio 0.67 is equal to (A) 1.0 m (B) 1.5 m (C) 2.0 m (D) 3 m

Last Answer : (B) 1.5 m

If the permeability of a soil is 0.8 mm/sec, the type of soil is (A) Gravel (B) Sand (C) Silt (D) Clay

Description : If the permeability of a soil is 0.8 mm/sec, the type of soil is (A) Gravel (B) Sand (C) Silt (D) Clay

Last Answer : (B) Sand

Hardening of cement occurs at (A) Rapid rate during the first few days and afterwards it continues to increase at a decreased rate (B) Slow rate during the first few days and afterwards it continues to increase at a rapid rate (C) Uniform rate throughout its age (D) None of these

Description : Hardening of cement occurs at (A) Rapid rate during the first few days and afterwards it continues to increase at a decreased rate (B) Slow rate during the first few days and afterwards it continues to increase at a rapid rate (C) Uniform rate throughout its age (D) None of these

Last Answer : Answer: Option D

Quick lime is (i) Slow in setting (ii) Rapid in slacking (iii) Good in strength The correct answer is (A) Only (i) (B) Only (ii) (C) Both (i) and (ii) (D) Both (ii) and (

Description : Quick lime is (i) Slow in setting (ii) Rapid in slacking (iii) Good in strength The correct answer is (A) Only (i) (B) Only (ii) (C) Both (i) and (ii) (D) Both (ii) and (

Last Answer : Answer: Option C

A steel rod of sectional area 250 sq. mm connects two parallel walls 5 m apart. The nuts at the ends were tightened when the rod was heated to 100°C. If steel = 0.000012/C°, Esteel = 0.2 MN/mm2 , the tensile force developed at a temperature of 50°C, is (A) 80 N/mm2 (B) 100 N/mm2 (C) 120 N/mm2 (D) 150 N/mm2 Answer: Option

Description : A steel rod of sectional area 250 sq. mm connects two parallel walls 5 m apart. The nuts at the  ends were tightened when the rod was heated to 100°C. If steel = 0.000012/C°, Esteel = 0.2  MN/mm2 , the ... N/mm2 (B) 100 N/mm2 (C) 120 N/mm2 (D) 150 N/mm2 Answer: Option 

Last Answer : (C) 120 N/mm

Froth floatation is used for (A) Washing fine coal dust (< 0.5 mm size) (B) Washing lump coal (> 80 mm size) (C) Removing ash from the coal based on difference in specific gravity of coal and ash

Description : Froth floatation is used for (A) Washing fine coal dust (< 0.5 mm size) (B) Washing lump coal (> 80 mm size) (C) Removing ash from the coal based on difference in specific gravity of coal and ash

Last Answer : (A) Washing fine coal dust (< 0.5 mm size)

A coarse-grained soil has a voids ratio 0.75, and specific gravity as 2.75. The critical gradient at which quick sand condition occurs, is (A) 0.25 (B) 0.50 (C) 0.75 (D) 1.00

Description : A coarse-grained soil has a voids ratio 0.75, and specific gravity as 2.75. The critical gradient at which quick sand condition occurs, is (A) 0.25 (B) 0.50 (C) 0.75 (D) 1.00

Last Answer : (D) 1.00

Which of the following operational problems relate to the functioning of rapid gravity filter ? 1. Inadequate media comprising filter bed 2. Sludge bulking 3. Mud balls 4. Negative head 5. Incrustation of media (a) 1, 3, 4 and 5 only (b) 1, 2, 3 and 4 only (c) 2, 3, 4 and 5 only (d) 1, 2, 3, 4 and 5

Description : Which of the following operational problems relate to the functioning of rapid gravity filter ? 1. Inadequate media comprising filter bed 2. Sludge bulking 3. Mud balls 4. Negative head 5. Incrustation of media (a) 1, 3, 4 and 5 ... 2, 3 and 4 only (c) 2, 3, 4 and 5 only (d) 1, 2, 3, 4 and 5

Last Answer : (a) 1, 3, 4 and 5 only

a rapid gravity filter (A) Raw water from the source is supplied (B) Disinfected raw water is supplied (C) Raw water passed through coagulation tank is supplied (D) None of these

Description : a rapid gravity filter  (A) Raw water from the source is supplied  (B) Disinfected raw water is supplied  (C) Raw water passed through coagulation tank is supplied  (D) None of these

Last Answer : (C) Raw water passed through coagulation tank is supplied 

The stresses developed in concrete and steel in reinforced concrete beam 25 cm width and 70 cm effective depth, are 62.5 kg/cm2 and 250 kg/cm2 respectively. If m = 15, the depth of its neutral axis is (A) 20 cm (B) 25 cm (C) 30 cm (D) 35 cm

Description : The stresses developed in concrete and steel in reinforced concrete beam 25 cm width and 70 cm effective depth, are 62.5 kg/cm2 and 250 kg/cm2 respectively. If m = 15, the depth of its neutral axis is (A) 20 cm (B) 25 cm (C) 30 cm (D) 35 cm

Last Answer : Answer: Option C

If V is speed of a moving vehicle, r is radius of the curve, g is the acceleration due to gravity, W is the width of the carriageway, the super elevation is (A) WV/gr (B) W²V/gr (C) WV²/gr (D) WV/gr²

Description : If V is speed of a moving vehicle, r is radius of the curve, g is the acceleration due to gravity, W is the width of the carriageway, the super elevation is (A) WV/gr (B) W²V/gr (C) WV²/gr (D) WV/gr²

Last Answer : Answer: Option C

The period of cleaning of a slow sand filter, is usually (A) 5 to 10 days (B) Two weeks to three weeks (C) One month to three months (D) Three months to six months

Description : The period of cleaning of a slow sand filter, is usually (A) 5 to 10 days (B) Two weeks to three weeks (C) One month to three months (D) Three months to six months

Last Answer : (C) One month to three months

The static deflection of a spring under gravity, when a mass of 1 kg is suspended from it, is 1 mm. Assume the acceleration due to gravity g = 10 m/s^2. The natural frequency of this spring-mass system (in rad/s) is A 100 B 150 C 200 D 250

Description : The static deflection of a spring under gravity, when a mass of 1 kg is suspended from it, is 1 mm. Assume the acceleration due to gravity g = 10 m/s^2. The natural frequency of this spring-mass system (in rad/s) is A 100 B 150 C 200 D 250

Last Answer : A 100

In slabs the Maximum horizontal distance between parallel main reinforcement should not exceed i.Three times effective depth ii Five times effective depth iii 300mm iv 450 mm [ A ] i and iii [ B ] i and iv [ C ] ii and iii [ D ] ii and iv

Description : In slabs the Maximum horizontal distance between parallel main reinforcement should not exceed i.Three times effective depth ii Five times effective depth iii 300mm iv 450 mm [ A ] i and iii [ B ] i and iv [ C ] ii and iii [ D ] ii and iv

Last Answer : [ A ] i and iii

The Maximum spacing of Secondary reinforcement in slabs should be [ A ] Less than 450 mm [ B ] Less than 300 mm [ C ] Smaller of three times the effective depth and 450 mm [ D ] Smaller of five times the effective depth and 450 mm

Description : The Maximum spacing of Secondary reinforcement in slabs should be [ A ] Less than 450 mm [ B ] Less than 300 mm [ C ] Smaller of three times the effective depth and 450 mm [ D ] Smaller of five times the effective depth and 450 mm

Last Answer : [ D ] Smaller of five times the effective depth and 450 mm

A tube mill compared to a ball mill (A) Has a higher length/diameter ratio(B) Produces a coarser product(C) Has a higher diameter/length ratio(D) Uses much larger balls

Description : A tube mill compared to a ball mill (A) Has a higher length/diameter ratio (B) Produces a coarser product (C) Has a higher diameter/length ratio (D) Uses much larger balls

Last Answer : (A) Has a higher length/diameter ratio

A compound bar consists of two bars of equal length. Steel bar cross-section is 3500 mm2 and that of brass bar is 3000 mm2 . These are subjected to a compressive load 100,000 N. If Eb = 0.2 MN/mm2 and Eb = 0.1 MN/mm2 , the stresses developed are: (A) b = 10 N/mm2s = 20 N/mm2(B) b = 8 N/mm2s = 16 N/mm2(C) b = 6 N/mm2s = 12 N/mm2(D) b = 5 N/mm2s = 10 N/mm

Description : A compound bar consists of two bars of equal length. Steel bar cross-section is 3500 mm2 and that  of brass bar is 3000 mm2 . These are subjected to a compressive load 100,000 N. If Eb = 0.2  MN/mm2  and Eb = 0.1 ... 6 N/mm2 s  = 12 N/mm2 (D) b = 5 N/mm2 s  = 10 N/mm

Last Answer : (A) b = 10 N/mm2 s  = 20 N/mm

Efficiency of removing bacterias from raw water by a slow sand filter, is (A) 80% to 81% (B) 85% to 86% (C) 90% to 97% (D) 98% to 99%

Description : Efficiency of removing bacterias from raw water by a slow sand filter, is (A) 80% to 81% (B) 85% to 86% (C) 90% to 97% (D) 98% to 99%

Last Answer : (D) 98% to 99%