Environmental Engineering Sheet 21
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1) Question.
The chlorine demand of a water sample was found to be 0.2 mg/I. The amount of bleaching powder containing 30% available chlorine to be added to treat one litre of such a water sample is:
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2) Question.
Which of the following pairs are correctly matched?
1. Lime soda process...............Softening.
2. Nalgonda technique..............Fluoride removal
3. Aeration..............Coagulation.
4. Ozonation............Disinfection.
Select the correct answer using the codes below:
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3) Question.
Type II settling in water treatment is defined as
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4) Question.
Consider the following statements in respect of slow sand filters:
1. Qualitywise they are more efficnet than Rapid Sand filters.
2. They need periodic backwashing
3. Their flow rate is much smaller than that of pressure filters.
Of these statements
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5) Question.
Consider the following statements regarding confined aquifers:
1. The aquifer is bound at top and below by impervious strata
2. The pressure of water is greater than atmospheric pressure
3. A tube well sunk in such an aquifer starts flowing always by itself
4. The auifer is fully saturated.
Of the above statements
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6) Question.
Sewage sickness relates to
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7) Question.
Under Indain conditions, the average per capita contribution of BOD is
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8) Question.
BOD is preferred to COD as an index of sewage concentration because
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9) Question.
Which one of the following statements is true of trickling filter sludge?
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10) Question.
When the coefficient of rugosity is increased from 0.01 to 0.02, the gradient of pipe of a given diameter to carry the same flow at the same velocity will be
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11) Question.
manholes are, generally located -
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12) Question.
For the sewers of diameter more than 600 mm, the type of joint preferred is -
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13) Question.
For the sewers of diameter less than 600 mm, the type of joint preferred is -
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14) Question.
An egg-shaped cross-section of a sewer -
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15) Question.
The cross-section recommended for separate system of sewerage is -
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16) Question.
Egg-shaped sewers are generally used for -
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17) Question.
For house drainage and lateral connections, we shall use -
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18) Question.
The internal diameter of the sewer should not be less than -
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19) Question.
The storm sewers are essentially required to -
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20) Question.
The sanitation system in which a small portion of storm water is allowed to enter in the sanitary of the sewers and the remaining storm water flows in separate set of sewers, is known as -
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