MCQ
17861. The max" permissible total solid content in water for domestic purposes should not exceed-
300 ppm
400 ppm
500 ppm
1000 ppm
17862. The open wells or dug wells are also known as-
shallow wells
percolation wells
draw wells
all of these
17863. What do you mean by BOD?
Best organized demand
Biochemical oxygen demand
Before oxidation damage
Bacteria of damage
Job Preparation
Civil MCQ
Himalay Sen Sir
Civil Engineering classroom
এনভায়রনমেন্টাল ইঞ্জিনিয়ারিং
environmental engineering
ব্যাখ্যা: ব্যাখ্যা: The full name of BOD is Biochemical Oxygen Demand. BOD refers to the amount of dissolved oxygen (DO) that arrobic organism need in order to break down organic naterial in water over time.
17864. The maximum acidity in water will occur at a pH value of-
0
7
2
14
17865. The presence of bacteria in water causes-
hardness
diseases
alkalinity
bad taste
17866. The presence of hydrogen sulphide in water causes-
softening
acidity
alkalinity
bad taste
17867. The groundwater is generally free from impurities.
suspended
dissolved
17868. The design period for a water supply project is taken as-
5 to 10 years
15 to 20 years
10 to 15 years
20 to 30 years
17869. The maximum permissible turbidity for domestic supplies, on silica scale is-
5 to 10 ppm
20 to 30 ppm
10 to 20 ppm
30 to 40 ppm
17870. Suspended impurities consist of-
iron
bacteria
chlorine
all of these
17871. pH value is a symbol for ---concentration.
magnesium
hydrogen
calcium
sodium
17872. The water obtained from is generally known as sub-surface water---
rain
reservoirs
rivers
artesian wells
17873. The most important source of water for public water supply is-
lake
pond
river
sea
17874. The water obtained from a lake is known as surface water.
Agree
Disagree
17875. Absolute pure water is good for health.
right
wrong
17876. The water bearing strata i.e. layers of sand, gravel etc. is called-
an aquifer
zone of saturation
an aquifuge
an aquiclude
17877. The quality of tube well water is ---as compaired to surface water
good
poor
17878. The presence of sodium chloride in water-
stops epidemic
increases hardness of water
causes bad taste
softens the water
17879. The maximum permissible colour for domestic supplies, on platinum cobalt scale is-
5 to 10 ppm
10 to 20 ppm
20 to 30 ppm
30 to 40 ppm
17880. The maximum permissible temperature for domestic supply is-
5 to 10°C
10 to 15°C
15 to 20°C
20 to 25°C