A slow sand filter is cleaned if its filter head is higher than (A) 10 cm to 20 cm (B) 20 cm to 40 cm (C) 40 cm to 70 cm (D) 70 cm to 120 cm

A slow sand filter is cleaned if its filter head is higher than 

(A) 10 cm to 20 cm 

(B) 20 cm to 40 cm 

(C) 40 cm to 70 cm 

(D) 70 cm to 120 cm

by

1 Answer

Answer :

(D) 70 cm to 120 cm

by

Related questions

A slow sand filter is cleaned if its filter head is higher than (A) 10 cm to 20 cm (B) 20 cm to 40 cm (C) 40 cm to 70 cm (D) 70 cm to 120 cm

Description : A slow sand filter is cleaned if its filter head is higher than (A) 10 cm to 20 cm (B) 20 cm to 40 cm (C) 40 cm to 70 cm (D) 70 cm to 120 cm

Last Answer : (D) 70 cm to 120 cm

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

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

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 

Water filtration rate in a slow sand filter ranges from __________ litres/m2 /hr. (A) 10 to 20 (B) 100 to 200 (C) 1500 to 2500(D) 4000 to 5000

Description : Water filtration rate in a slow sand filter ranges from __________ litres/m2 /hr. (A) 10 to 20 (B) 100 to 200 (C) 1500 to 2500 (D) 4000 to 5000

Last Answer : (B) 100 to 200

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

For batching 1:3:6 concrete mix by volume, the ingredients required per bag of 50 kg cement, are: (A) 70 litres of sand and 120 litres of aggregates (B) 70 kg of sand and 140 litres of aggregates (C) 105 litres of sand and 140 litres of aggregates (D) 105 litres of sand and 210 litres of aggregates

Description : For batching 1:3:6 concrete mix by volume, the ingredients required per bag of 50 kg cement, are: (A) 70 litres of sand and 120 litres of aggregates (B) 70 kg of sand and 140 litres of ... C) 105 litres of sand and 140 litres of aggregates (D) 105 litres of sand and 210 litres of aggregates

Last Answer : Answer: Option D

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

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%

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

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

After cleaning a slow sand filter, the filtered water is not used for (A) 6 hours to 12 hours (B) 12 hours to 18 hours (C) 18 hours to 24 hours (D) 24 hours to 36 hours

Description : After cleaning a slow sand filter, the filtered water is not used for  (A) 6 hours to 12 hours  (B) 12 hours to 18 hours  (C) 18 hours to 24 hours  (D) 24 hours to 36 hours 

Last Answer : (D) 24 hours to 36 hours 

To prevent movement of moisture from sub-grade to road pavement on embankments about 0.6 m to 1 m higher than water table, the thickness of cut off layer of coarse sand used, is (A) 15 cm (B) 20 cm (C) 30 cm (D) None of these

Description : To prevent movement of moisture from sub-grade to road pavement on embankments about 0.6 m to 1 m higher than water table, the thickness of cut off layer of coarse sand used, is (A) 15 cm (B) 20 cm (C) 30 cm (D) None of these

Last Answer : Answer: Option D

For making fly-ash building bricks, the following mix of fly-ash, sand and lime, is (A) 80 : 13 : 7 (B) 70 : 20 : 10 (C) 60 : 35 : 5 (D) None of these

Description : For making fly-ash building bricks, the following mix of fly-ash, sand and lime, is (A) 80 : 13 : 7 (B) 70 : 20 : 10 (C) 60 : 35 : 5 (D) None of these

Last Answer : Answer: Option A

Which of the following represents hardest grade of bitumen? (A) 30/40 (B) 60/70 (C) 80/100 (D) 100/120

Description : Which of the following represents hardest grade of bitumen? (A) 30/40 (B) 60/70 (C) 80/100 (D) 100/120

Last Answer : Answer: Option A

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

Dust content in raw blast furnace gas is about __________ gm/Nm3 ; hence it is cleaned to the dust level of about < 10 mg /Nm3 before use. (A) 15-30 (B) 1-2 (C) 70-100 (D) 150-200

Description : Dust content in raw blast furnace gas is about __________ gm/Nm3 ; hence it is cleaned to the dust level of about < 10 mg /Nm3 before use. (A) 15-30 (B) 1-2 (C) 70-100 (D) 150-200

Last Answer : (A) 15-30

Minimum thickness of a layer of fine sand required to cut off capillary rise of water completely, should be (A) 40 cm(B) 52 cm (C) 64 cm (D) 76 cm

Description : Minimum thickness of a layer of fine sand required to cut off capillary rise of water completely, should be (A) 40 cm (B) 52 cm (C) 64 cm (D) 76 cm

Last Answer : Answer: Option D

Standard disc Plough consists of steel disc of _ diameter a) 20 to 40 cm. c) 60 to 90 cm b) 30 to 60 cm. d) 70 to 100 cm

Description : Standard disc Plough consists of steel disc of _ diameter a) 20 to 40 cm. c) 60 to 90 cm b) 30 to 60 cm. d) 70 to 100 cm

Last Answer :  60 to 90 cm

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

In India, which one of the following should be considered the right combination of the age in days and live body weight in kg for a lamb for its weaning ? (A) 20 days to 30 days and 6 kg to 7 kg (B) 45 days to 60 days and 8 kg to 10 kg (C) 105 days to 120 days and 18 kg to 21 kg (D) 75 days to 90 days and 12 kg to 15 kg (E) 55 days to 70 days and 9 kg to 11 kg

Description : In India, which one of the following should be considered the right combination of the age in days and live body weight in kg for a lamb for its weaning ? (A) 20 days to 30 days and 6 kg to 7 kg (B) 45 days to 60 ... (D) 75 days to 90 days and 12 kg to 15 kg (E) 55 days to 70 days and 9 kg to 11 kg

Last Answer : (C) 105 days to 120 days and 18 kg to 21 kg

The width of nursery bed should be ….. a. 100-120 cm b. 30-60 cm c. 15-30 cm d. 70 -80 cm

Description : The width of nursery bed should be ….. a. 100-120 cm b. 30-60 cm c. 15-30 cm d. 70 -80 cm

Last Answer : a. 100-120 cm

The width of nursery bed should be ….. a. 100-120 cm b. 30-60 cm c. 15-30 cm d. 70 -80 cm

Description : The width of nursery bed should be ….. a. 100-120 cm b. 30-60 cm c. 15-30 cm d. 70 -80 cm

Last Answer : a. 100-120 cm

Water filtration rate in a rapid sand filter ranges from __________ kilolitres/m2 /hr. (A) 0.1 to 1 (B) 3 to 6 (C) 10 to 15 (D) 15 to 20

Description : Water filtration rate in a rapid sand filter ranges from __________ kilolitres/m2 /hr. (A) 0.1 to 1 (B) 3 to 6 (C) 10 to 15 (D) 15 to 20

Last Answer : (B) 3 to 6

What is the limit of MG/DL, of blood sugar in the normal person at the time of fast? (1) 40-60 (2) 120-150 (3) 70-100 (4) 160-200

Description : What is the limit of MG/DL, of blood sugar in the normal person at the time of fast? (1) 40-60 (2) 120-150 (3) 70-100 (4) 160-200

Last Answer : (3) 70-100 Explanation: The mean normal blood glucose level in humans is about 4 mM (4 mmol/L, or 72 mg/dL, i.e. milligrams/deciliter); however, this level fluctuates throughout the day. Glucose ... day (termed "the fasting level"), and rise after meals for an hour or two by a few millimolar.

What is the limit of MG/DL of blood sugar in the normal person at the time of fast ? (1) 40-60 (2) 120-150 (3) 70-100 (4) 160-200

Description : What is the limit of MG/DL of blood sugar in the normal person at the time of fast ? (1) 40-60 (2) 120-150 (3) 70-100 (4) 160-200

Last Answer : 70-100

Bucket A has twice the capacity as bucket B. It takes 120 turns for bucket A to fill the empty dumper. How many turns it will take for both the buckets A and B, having each turn together to fill the empty dumper. A) 40 B) 50 C) 70 D) 80

Description : Bucket A has twice the capacity as bucket B. It takes 120 turns for bucket A to fill the empty dumper. How many turns it will take for both the buckets A and B, having each turn together to fill the empty dumper. A) 40 B) 50 C) 70 D) 80

Last Answer : D Let capacity of A be x litres Then capacity of B = x/2 litres Capacity of the dumper = 120x litres Required number of turns = 120x/ x =x/2 = 2 (120x)/3x =2430x/3x =80.

What is the intensity of sound in normal conversation? (a) 10-20 dB (b) 30-60 dB (c) 70-90 dB (d) 120-150 dB

Description : What is the intensity of sound in normal conversation? (a) 10-20 dB (b) 30-60 dB (c) 70-90 dB (d) 120-150 dB

Last Answer : b) 30-60 dB

When was the last time that you cleaned or changed your air-distribution unit/system filter?

Description : When was the last time that you cleaned or changed your air-distribution unit/system filter?

Last Answer : I wash mine every new season, so 4 times a year. Doing it on a specific date helps remind me to clean it. I have no idea about your other questions, but I have a really good air/heating guy that even comes on Sundays and doesn’t charge extra.

How often does the filter on the Bunn ThermoFresh BTX-B have to be cleaned or replaced?

Description : How often does the filter on the Bunn ThermoFresh BTX-B have to be cleaned or replaced?

Last Answer : The filter on the Bunn ThermoFresh should probably be replaced every two or three brewings, as necessary.

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

To prevent movement of moisture from sub-grade to road pavement at the same level as that of water-table, thickness of a cut off layer of coarse sand, is (A) 15 cm (B) 20 cm (C) 30 cm (D) 45 cm

Description : To prevent movement of moisture from sub-grade to road pavement at the same level as that of water-table, thickness of a cut off layer of coarse sand, is (A) 15 cm (B) 20 cm (C) 30 cm (D) 45 cm

Last Answer : Answer: Option A

A singly reinforced concrete beam of 25 cm width and 70 cm effective depth is provided with 18.75 cm2 steel. If the modular ratio (m) is 15, the depth of the neutral axis, is (A) 20 cm (B) 25 cm (C) 30 cm (D) 35 cm

Description : A singly reinforced concrete beam of 25 cm width and 70 cm effective depth is provided with 18.75 cm2 steel. If the modular ratio (m) is 15, the depth of the neutral axis, is (A) 20 cm (B) 25 cm (C) 30 cm (D) 35 cm

Last Answer : Answer: Option C

Area of steel required per metre width of pavement for a length of 20 m for design wheel load 6300 kg and permissible stress in steel 1400 kg/cm2 , is (A) 70 kg/sq cm (B) 80 kg/sq cm (C) 90 kg/sq cm (D) 100 kg/sq cm

Description : Area of steel required per metre width of pavement for a length of 20 m for design wheel load 6300 kg and permissible stress in steel 1400 kg/cm2 , is (A) 70 kg/sq cm (B) 80 kg/sq cm (C) 90 kg/sq cm (D) 100 kg/sq cm

Last Answer : Answer: Option C

If the width of carriage way is 12.5 metres, outer edge 50 cm higher than the inner edge, the required super elevation is (A) 50 cm (B) 1 in 25 (C) 1 in 400 (D) 1 in 40

Description : If the width of carriage way is 12.5 metres, outer edge 50 cm higher than the inner edge, the required super elevation is (A) 50 cm (B) 1 in 25 (C) 1 in 400 (D) 1 in 40

Last Answer : Answer: Option B

Two concave lenses of 60 cm focal length are cemented on either side of a convex lens of 15 cm focal length. The focal length of the combination is (A) 10 cm (B) 20 cm (C) 30 cm (D) 40 cm

Description : Two concave lenses of 60 cm focal length are cemented on either side of a convex lens of 15 cm  focal length. The focal length of the combination is  (A) 10 cm  (B) 20 cm  (C) 30 cm  (D) 40 cm 

Last Answer : (C) 30 cm 

If the width of a pavement slab is 7.5 m, thickness 20 cm and working stress 1400 kg/cm2 , spacing of 10 mm tie bars for the longitudinal joint, is (A) 10 cm (B) 20 cm (C) 30 cm (D) 40 cm

Description : If the width of a pavement slab is 7.5 m, thickness 20 cm and working stress 1400 kg/cm2 , spacing of 10 mm tie bars for the longitudinal joint, is (A) 10 cm (B) 20 cm (C) 30 cm (D) 40 cm

Last Answer : Answer: Option C

Mud balls may be removed by (A) Breaking and washing (B) Washing the filter with a solution of caustic soda (C) Removing, cleaning and replacing the damaged sand (D) All the above

Description : Mud balls may be removed by (A) Breaking and washing (B) Washing the filter with a solution of caustic soda (C) Removing, cleaning and replacing the damaged sand (D) All the above

Last Answer : (D) All the above

The U.C. (uniformity coefficient) D60/D10 for the best filter media sand should be (A) 2 (B) 3 (C) 4 (D) 5

Description : The U.C. (uniformity coefficient) D60/D10 for the best filter media sand should be  (A) 2  (B) 3  (C) 4  (D) 5

Last Answer : (A) 2

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

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

The head light of vehicles should be such that its lower beam illuminates objects at (A) 10 m (B) 20 m (C) 30 m (D) 40 m

Description : The head light of vehicles should be such that its lower beam illuminates objects at (A) 10 m (B) 20 m (C) 30 m (D) 40 m

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 

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

Description : 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 

Last Answer : (D) All the above 

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 

Littoral drift (A) Is the raised line of sand, parallel to the sea coast (B) Is the slow movement of surface water at sea caused by the wind (C) Is a current parallel to the shore, caused due to tangential component of the wind (D) Is a current perpendicular to the shore line caused due to wind

Description : Littoral drift (A) Is the raised line of sand, parallel to the sea coast (B) Is the slow movement of surface water at sea caused by the wind (C) Is a current parallel to the shore, caused due to tangential component of the wind (D) Is a current perpendicular to the shore line caused due to wind

Last Answer : (C) Is a current parallel to the shore, caused due to tangential component of the wind

If the depth of moist sand in a cylinder is 15 cm and the depth of the sand when fully inundated with water is 12 cm, the bulking of the moist sand, is (A) 10 % (B) 12 % (C) 15 % (D) 25%

Description : If the depth of moist sand in a cylinder is 15 cm and the depth of the sand when fully inundated with water is 12 cm, the bulking of the moist sand, is (A) 10 % (B) 12 % (C) 15 % (D) 25%

Last Answer : Answer: Option D

Pick up the incorrect statement from the following. For performing compressive strength test of cement (A) Cement and standard sand mortar are used in the ratio of 1 : 3 (B) Water is added at the rate of (P/4) + 3.0 percentage of water where P is the percentage of water for standard consistency (C) A cube mould of 10 cm × 10 cm × 10 cm is used (D) The prepared moulds are kept in a atmosphere of 50% relative humidity

Description : Pick up the incorrect statement from the following. For performing compressive strength test of cement (A) Cement and standard sand mortar are used in the ratio of 1 : 3 (B) Water is added at the ... cm 10 cm is used (D) The prepared moulds are kept in a atmosphere of 50% relative humidity

Last Answer : Answer: Option A

Standard disc plough diameter size is A. 40 to 60 cm C. 70 to 90 cm B. 60 to 90 cm D. 50 to 70 cm

Description : Standard disc plough diameter size is A. 40 to 60 cm C. 70 to 90 cm B. 60 to 90 cm D. 50 to 70 cm

Last Answer : 60 to 90 cm

According to I.S.: 456, 1978 the thickness of reinforced concrete footing on piles at its edges, is kept less than (A) 20 cm (B) 30 cm (C) 40 cm (D) 75 cm

Description : According to I.S.: 456, 1978 the thickness of reinforced concrete footing on piles at its edges, is kept less than (A) 20 cm (B) 30 cm (C) 40 cm (D) 75 cm

Last Answer : Answer: Option B