Q.1

A centrifugal pump is required to be primed before starting if it is located

  • at higher level than water level of reservoir
  • at lower level than water level of reservoir
  • both (a) and (b)
  • neither (a) nor (b).
Q.2

The permissible amount of nitrites present in potable water, is

  • 10 ppm
  • 15 ppm
  • 20 ppm
  • 45 ppm
  • Nil.
Q.3

If the average daily demand of a city ofpopulation, ism.l.d., the maximum daily demand is

  • 24 mld
  • 30 mld
  • 36 mld
  • 54 mld.
Q.4

Pickup the incorrect statement from the following :

  • The invert of pressure conduit is independent of the grade of the hydraulic gradient line
  • The pressure conduits may be taken uphill upto a maximum height of 8.3 m
  • Aqueducts and tunnels sections are generally kept circular
  • None of these.
Q.5

Hardness of water is caused by

  • presence of soap lather
  • presence of chlorides and sulphates of sodium and potassium
  • presence of bicarbonates, sulphates or chlorides of calcium and magnesium
  • turbidity.
Q.6

The process of passing water through beds of granular materials, is called

  • screening
  • sedimentation
  • filtration
  • none of these.
Q.7

The maximum pressure which the pipe can withstand without any leakage during hydrostatic pressure test, is called

  • Working pressure
  • Design pressure
  • Test pressure
  • Hydrostatic pressure.
Q.8

Water having pH value asis

  • alkaline
  • acidic
  • neutral
  • none of these.
Q.9

Recuperation test is carried out to determine

  • turbidity of water
  • pH value of water
  • yield of well
  • discharge from a well.
Q.10

Detention period of a settling tank is

  • average theoretical time required for water to flow through the tank
  • time required for flow of water to fill the tank fully
  • average time for which water is retained in tank
  • ratio of volume of basin of a sedimentation tank to the rate of flow
  • all the above.
Q.11

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

  • 10 cm to 20 cm
  • 20 cm to 40 cm
  • 40 cm to 70 cm
  • 70 cm to 120 cm
  • 120 cm to 150 cm.
Q.12

If Q is discharge is cubicmetres per sec and D is the economical diameter of the pipe. According to Lea

  • D = 0.67 to 0.87 Q
  • D = 0.77 to 0.97 Q
  • D = 0.97 to 1.22 Q
  • D = 1.22 to 1.33 Q.
Q.13

Filtration of water is done to remove

  • colour
  • odour
  • turbidity
  • pathogenic bacteria
  • all the above.
Q.14

Alum is chemically

  • Copper sulphate
  • Aluminium sulphate
  • Ferrous sulphate
  • Ferric sulphate.
Q.15

Pick up the incorrect statement from the following :

  • Water disinfected with ozone is free from any odour
  • Ozone removes bacterias as well as colour and odour
  • ozonised water becomes tasteless
  • None of these.
Q.16

A strainer type well sunk through three pervious layers intervened by three impervious aquicludes, draws water from

  • top most pervious layer
  • central pervious layer
  • lowest pervious layer
  • all the pervious layers.
Q.17

Water to the consumers may be supplied from

  • infiltration galleries connected to sump well
  • infiltration well dug out on the banks of rivers
  • ranney wells sunk to the water level
  • all the above.
Q.18

Generally, first portion of a logistic curve for the population growth of a developing city, represents the growth of

  • increasing
  • decreasing
  • constant
  • all the above.
Q.19

Pick up the correct statement from the following :

  • Air lift pumps are generally used for pumping water from deep wells
  • Jet pumps are generally used for pumping water from small wells
  • The hydraulic ram works on the principle of water hammer
  • Rotary pumps are provided cams which rotate in opposite direction
  • all the above.
Q.20

The order of existence of three portions of water in a reservoir from the bottom to top is

  • useful storage + surcharge storage + dead storage
  • useful storage + dead storage + surcharge storage
  • dead storage + useful storage + surcharge storage
  • surcharge storage + useful storage + dead storage
  • none of these.
Q.21

Pick up the correct statement from the following :

  • Air lift pumps are generally used for pumping water from deep wells
  • Jet pumps are generally used for pumping water from small wells
  • The hydraulic ram works on the principle of water hammer
  • Rotary pumps are provided cams which rotate in opposite direction
  • all the above.
Q.22

Perched acquifers are generally found

  • on the surface of the ground
  • below the surface of the ground but above water table
  • below the water table
  • all the above.
Q.23

Turbidity of water is expressed

  • in ppm
  • in numbers in an arbitrary scale
  • by pH value
  • by colour code.
Q.24

The approximate diameter of a water mains for supplying 7.2 mld with a velocity 1.2 m/sec, is

  • 24 cm
  • 26 cm
  • 28 cm
  • 30 cm
  • 32 cm.
Q.25

Perched acquifers are generally found

  • on the surface of the ground
  • below the surface of the ground but above water table
  • below the water table
  • all the above.
Q.26

At the socket and spigot joint,

  • enlarged end of the pipe is called socket
  • normal end of the pipe is called spigot
  • spigot is fitted into the socket
  • molten lead is used for water proofing
  • all the above.
Q.27

The water level in an open well was depressed by pumping 2.5 m and recuperated 2.m in 3 hours andminutes. The yield of the well per minute is

  • 0.0033
  • 0.0044
  • 0.0055
  • 0.0066
Q.28

During treatment of water, sedimentation is done

  • before filtration
  • after filtration
  • simultaneously with filtration
  • along with chlorination.
Q.29

Hard water contains

  • calcium
  • magnesium bicarbonates
  • magnesium sulphate
  • all the above.
Q.30

Pick up the correct statement from the following :

  • The internal pressure within a pipe, is caused due to water head and hammer pressure
  • The internal pressure in a pipe running full is equal to vertical ordinate between hydraulic gradient line and centre of the pipe
  • In pressure pipes with water at rest, the pressure is equal to water head
  • Sudden closure of a valve, causes the water hammer pressure
  • All the above.
0 h : 0 m : 1 s