ENVIRONMENTAL ENGINEERING QUIZ

For a given discharge, the efficiency of sedimentation tank can be increased by

Decreasing the depth of tank

Increasing the surface area of tank

Increasing the depth of tank

Decreasing the surface area of tank

TRUE ANSWER : ?
YOUR ANSWER : ?

The pathogens can be killed by

Oxidation

None of these

Chlorination

Nitrification

TRUE ANSWER : ?
YOUR ANSWER : ?

Activated carbon is used for

Disinfection

Removing corrosiveness

Removing hardness

Removing odours

TRUE ANSWER : ?
YOUR ANSWER : ?

If the time of concentration is 9 minutes, then the intensity of rainfall according to British Ministry of Health formula will be

40 mm/hr

20 mm/hr

10 mm/hr

4 mm/hr

TRUE ANSWER : ?
YOUR ANSWER : ?

The dissolved oxygen level in natural unpolluted waters at normal temperature is found to be of the order of

100 mg/liter

1 mg/liter

10 mg/liter

1000 mg/liter

TRUE ANSWER : ?
YOUR ANSWER : ?

The design discharge for the separate sewer system shall be taken as

Equal to dry weather flow (DWF)

2 × DWF

6 × DWF

3 × DWF

TRUE ANSWER : ?
YOUR ANSWER : ?

The correct relation between theoretical oxygen demand (TOD), Biochemical oxygen demand (BOD) and Chemical oxygen demand (COD) is given by

COD > BOD > TOD

BOD > COD > TOD

TOD > BOD > COD

TOD > COD > BOD

TRUE ANSWER : ?
YOUR ANSWER : ?

The main disadvantage of oxidation pond is that

Maintenance and operation cost are high

None of these

Large area is required for construction

BOD removal is very low

TRUE ANSWER : ?
YOUR ANSWER : ?

The major disadvantage of lime soda process of water softening is that

It is unsuitable for softening the water of excessive hardness

The effluent cannot be reduced to zero hardness

Huge amount of precipitate is formed which creates a disposal problem

It is unsuitable for turbid and acidic water

TRUE ANSWER : ?
YOUR ANSWER : ?

Assertion A: The consumption of water increases with increase in the distribution pressure.Reason R: Higher distribution pressure causes more loss and waste of waterSelect your answer according to the coding system given below

A is true but R is false

Both A and R is true and R is the correct explanation of A

Both A and R is true but R is not the correct explanation of A

A is false but R is true

TRUE ANSWER : ?
YOUR ANSWER : ?