In pressure supply mains, water hammer pressure is reduced by providing
(A) Sluice valves
(B) Air valves
(C) Pressure relief valves
(D) None of these
Description : Pressure relief valves are provided in water mains (A) To reduce the pressure (B) At low points (C) Upstream of sluice (D) All the above
Last Answer : (D) All the above
Description : Sluice valves are fitted in a distribution system (A) Along straight length of pipes at suitable intervals (B) At the junctions of the pipes (C) At the branching off points of sub-mains (D) All the above
Description : Air inlet valve in water mains, is generally provided at (A) Summit of the pipe (B) Upstream of sluice valve (C) Downstream of sluice valve (D) Both (a) and (c) of above
Last Answer : (D) Both (a) and (c) of above
Description : Sluice valves in main water supplies (A) Are used to regulate the flow of water in pipes (B) Are spaced about 5 km apart (C) Are usually placed at the summits (D) All the above
Description : The difference in the reservoir level and the lowest point of the water mains is 180 m. The expected pressure due to water hammer is 7.5 kg/cm2 in a pressure conduit of diameter 1 m. Assuming the efficiency of the ... , is (A) 10 mm (B) 15 mm (C) 20 mm (D) 25 mm
Last Answer : (C) 20 mm
Description : The purpose of a surge tank is (A) To control the pressure variations due to rapid changes in the pipe line flow (B) To eliminate water hammer possibilities (C) To regulate flow of water to turbines by providing necessary retarding head of water (D) All of the above
Last Answer : Answer: Option D
Description : Air valves are generally provided in pressure pipes of water supply (A) At pipe junctions (B) At summits (C) At low points (D) Near service pipes
Last Answer : (B) At summits
Description : Surge tanks are used (A) For storage water (B) To increase the velocity in a pipeline (C) As overflow valves (D) To guard against water hammer
Last Answer : (D) To guard against water hammer
Description : The total pressure on the surface of a vertical sluice gate 2 m x 1 m with its top 2 m surface being 0.5 m below the water level will be (A) 500 kg (B) 1000 kg (C) 1500 kg (D) 2000 kg
Description : Most commonly used pump for lifting water in water supply mains, is (A) Axial flow pump (B) Reciprocating pump (C) Rotary type pump (D) Centrifugal pumps
Last Answer : (A) Axial flow pump
Description : Distribution mains of any water supply, is normally designed for its average daily requirement (A) 100 % . (B) 150 % (C) 200 % (D) 225 %
Last Answer : (D) 225 %
Description : Foot valves provided in pumps are __________ valves. (A) Relief (B) Three/four way (C) Pressure reducing (D) Directional contro
Last Answer : (D) Directional control
Description : The lowest outlet sluice in a dam is provided (A) Below the dead storage (B) On the top level of dead storage (C) On the top level of useful storage (D) At the centre of the dam
Last Answer : (B) On the top level of dead storage
Description : As compared to crest of the normal portion of the weir, the crest of the under sluice portion of weir is kept at (A) Lower level (B) Higher level (C) Same level (D) Any of the above depending on the design
Last Answer : Answer: Option A
Description : If there are two canals taking off from each flank of a river, then there will be (A) One divides wall and one under-sluice (B) One divides wall and two under-sluices (C) Two divide walls and one under-sluice (D) Two divide walls and two under-sluices
Description : The factor affecting per capita demand, is (A) Size of the city (B) Climatic conditions (C) Pressure in water mains (D) All the above
Description : Pick up the incorrect statement from the following regarding fire hydrants (A) Fire hydrants are fitted in water mains at 100 m to 150 m apart at fire (B) The minimum water pressure hydrants, is kept 1.5 kg/ ... to 1.5 kg/cm2 is made available for 4 to 5 hours for constant use (D) None of these
Last Answer : (D) None of these
Description : When using multiple SAW arc systems (twin wires etc), the arcs often have different polarities or use all AC rather than DC polarity, this is to? a) Prevent arc blow between arcs b) To maximize productivity c) To even out the power factor on the mains supply d) Make it easier to initiate the arc
Last Answer : a) Prevent arc blow between arcs
Description : Before providing super-elevation on roads, the portion of the carriageway between the crown and the outer edge is made (A) To have a reduced fall (B) Horizontal (C) To have slope of the camber on the other half of the carriageway (D) None of these
Last Answer : Answer: Option C
Description : The advantage of providing super-elevation on roads, is (A) Higher speed of vehicles (B) Increased volume of traffic (C) Reduced maintenance cost of the roads (D) All the above
Description : When shear stress exceeds the permissible limit in a slab, then it is reduced by (A) Increasing the depth (B) Providing shear reinforcement (C) Using high strength steel (D) Using thinner bars but more in number
Description : The acceptable pressure drop at the farthest point in mains header of an industrial compressed air network is: a)0.3 bar b) 0.5 bar c) 1.0 bar d) 2 bar
Last Answer : a)0.3 bar
Description : A situation which is providing some relief from tax in whole or part is referred as _________ A. Tax Break B. Tax Evasion C. Tax Shifting D. None of the Above
Last Answer : A. Tax Break Explanation: Tax break is a term referring to any item which avoids taxes, including any tax exemption, tax deduction, or tax credit.
Description : Cement clinker is reduced to fine size by a (A) Roll crusher (B) Ball mill (C) Tube mill (D) Hammer mill
Last Answer : (C) Tube mill
Description : A shuttle valve will: a. Allow the accumulator to be emptied after engine shut down b. Reduce pump loading when normal system pressure is reached c. Automatically switched to a more appropriate source of hydraulic supply d. Operate on a rising pressure, higher than the Full Flow relief valve
Last Answer : c. Automatically switched to a more appropriate source of hydraulic supply
Description : The ensure proper growth of children's teeth, the quantity of fluoride used in water mains, is (A) 1 mg/litre (B) 2 mg/litre (C) 3 mg/litre (D) 5 mg/litre
Last Answer : (A) 1 mg/litre
Description : The approximate diameter of a water mains for supplying 7.2 mld with a velocity 1.2 m/sec, is (A) 24 cm (B) 26 cm (C) 28 cm (D) 30 cm
Last Answer : (D) 30 cm
Description : According to National Building Code, the hydrants in water mains is provided at minimum interval of (A) 50 m (B) 60 m (C) 75 m (D) 90 m
Last Answer : Option C
Description : Pick up the correct statement from the following: (A) Air lift pumps are generally used for pumping water from deep wells (B) Jet pumps are generally used for pumping water from small wells (C) The hydraulic ram works on the principle of water hammer (D) All the above
Description : Pick up the correct statement from the following: (A) The internal pressure within a pipe, is caused due to water head and hammer pressure (B) In pressure pipes with water at rest, the pressure ... (C) Sudden closure of a valve, causes the water hammer pressure (D) All the above
Description : In distribution pipes, air valves are provided at (A) Lower points (B) Junction points (C) Higher points (D) Anywhere
Last Answer : (C) Higher points
Description : Pick up the correct statement from the following: (A) O.M.C. refers to the moisture corresponding to the maximum point on the moisture content dry density curve (B) The line which shows moisture content dry ... void line (C) The free fall of hammer for compaction is 30.5 cm (D) All the above
Description : Pick up the correct statement from the following: (A) Air bubbles in casting produce a dull sound by tapping their surfaces lightly with a hammer (B) Cupola furnace is used for the manufacture of cast iron (C) Red short iron is of no value for welding purpose (D) All the above
Description : The pressure of fluid due to hammer blow is (A) Directly proportional to density of fluid (B) Inversely proportional to density of fluid (C) Directly proportional to (density)1/2 of fluid (D) Inversely proportional to (density)1/2 of fluid
Description : The hammer blow in pipes occurs when (A) There is excessive leakage in the pipe (B) The pipe bursts under high pressure of fluid (C) The flow of fluid through the pipe is suddenly brought to ... valve (D) The flow of fluid through the pipe is gradually brought to rest by closing of the valve
Description : Eradication of H.pylori along with gastric antisecretory drugs affords the following benefit(s): A. Faster relief of ulcer pain B. Faster ulcer healing C. Reduced chance of ulcer relapse D. Both ‘B’ and ‘C’ are correct
Last Answer : D. Both ‘B’ and ‘C’ are correct
Description : Contract farming consists of...... (A) hiring land by farmers on contract basis for cultivation (B) supply of agreed quantity of produce to agreed price to the company (C) company taking on ... and to give back to farmers (E) providing inputs by company to farmers for improving quality of produce
Last Answer : (C) company taking on lease basis farmers’ land for cultivation
Description : Contract farming consists of...... (A) hiring land by farmers on contract basis for cultivation (B) supply of agreed quantity of produce to agreed price to the company (C) company taking on lease ... and to give back to farmers (E) providing inputs by company to farmers for improving quality of prod
Last Answer : (D) processing cash crops, vegetables etc. by company and to give back to farmers
Description : Check valves are installed (A) On the delivery side of the pumping set (B) At the interconnections between polluted water system and a potable water system (C) Both (a) and (b) (D) Neither (a) nor (b)
Last Answer : (C) Both (a) and (b)
Description : The valves provided at low points of pipes to drain off water quickly under gravity, are called (A) Blow off valves (B) Drain valves (C) Sewer valves (D) All the above
Description : Supercharging is the process of a. supplying the engine with air at a density greater than the density of the surrounding atmosphere b. providing forced cooling air c. injecting excess fuel d. raising the exhaust pressure
Last Answer : ANSWER a. supplying the engine with air at a density greater than the density of the surrounding atmosphere
Description : Critical time for developing a water hammer, is the time required for (A) Closing the valve (B) The wave to travel from valve to the reservoir (C) The wave to travel from the valve to the reservoir and back (D) None of these
Last Answer : (C) The wave to travel from the valve to the reservoir and back
Description : 19. The water hammer in pipes occurs due to sudden change in the velocity of flowing liquid A) Agree B) Disagree
Last Answer : A
Description : The magnitude of water hammer depends upon the (A) Elastic properties of the pipe material (B) Elastic properties of the liquid flowing through the pipe (C) Speed at which the valve is closed (D) All of the above
Description : A supercharger is used in the engines of earthmoving machines at higher altitudes because (a) The ambient atmospheric pressure is less at higher altitudes (b) Four-cycle engines depend on the suction ... rugged enough for higher altitude (d) The ambient temperature is less as the altitude is higher
Last Answer : (a) The ambient atmospheric pressure is less at higher altitudes
Description : In distribution pipes, drain valves are provided at (A) Lower point (B) Higher point (C) Junction points (D) Anywhere
Last Answer : (A) Lower point
Description : Size, capacity and materials need be specified for (A) Bib-cocks (B) Stop-cocks (C) Ball valves (D) All the above
Description : If concrete compression test fails, should Schmidt hammer test be adopted as an alternative test to prove the concrete strength?
Last Answer : The Scmidt hammer test is based on the elastic rebound of hammer which presses on concrete surface and it measures the surface hardness of concrete. Since the test is very sensitive to the ... strength of concrete. Therefore, it may not be considered a good substitute for concrete compression test.
Description : A pile is being driven with a drop hammer weighing 1800 kg and having a free fall of 1.00 m. If the penetration with last blow is 5 mm, the load carrying capacity of the pile, -according to the Engineering News formula, is (A) 100 tonnes (B) 50 tonnes (C) 20 tonnes (D) 10 tonnes
Last Answer : (D) 10 tonnes