Pick up the incorrect statement from the following?

Related Mcqs:

1. Pick up the incorrect statement from the following ?

   A. Septic tanks are horizontal continuous flow type of sedimentation tanks
   B. Septic tanks are generally provided a detention period of 12 to 36 hours
   C. Septic tanks are completely covered and high vent shafts are provided for the escape of foul gases
   D. None of these

2. Pick up the incorrect statement from the following?

   A. The mixture of water and waste products, is called sewage
   B. The treated sewage effluents, are generally used for irrigating the crops
   C. The process of collecting, treating and disposing off the sewage, is called sewerage
   D. The old convergence system was definitely better than water carried sewerage system

3. Pick up the incorrect statement from the following for allowing workers to enter sewers_______________?

   A. The particular manhole and one manhole on upstream and one manhole on downstream should remain open for 30 minutes
   B. Proper tests for the presence of poisonous gases must be carried out
   C. The men entering the manhole should be advised to smoke in the sewer
   D. Warning signals should be erected

4. Pick up the incorrect size of stone ware sewers_________________?

   A. 52.5 cm
   B. 67.5 cm
   C. 82.5 cm
   D. None of these

5. Pick up the correct statement from the following ?

   A. The sewer pipes of sizes less than 0.4 m diameter are designed as running full at maximum discharge
   B. The sewer pipes of sizes greater than 0.4 m diameter are designed as running 2/3rd or 3/4th full at maximum discharge
   C. The minimum design velocity of sewer pipes is taken as 0.8 m/sec
   D. All the above

6. Pick up the correct statement from the following?

   A. The maximum rate of storm runoff is called peak drainage discharge
   B. Rational method of estimating peak run off, may be used precisely for areas less than 50 hectares
   C. The period after which the entire area starts contributing to the runoff, is called the time of concentration
   D. All the above

7. Pick up the correct statement from the following?

   A. Hydrogen sulphide gas in excess, may cause corrosion of concrete sewers
   B. 4 ppm of Dissolved Oxygen (D.O.) is ensured before discharging the treated sewage in river
   C. Solubility of oxygen in sewage is 95% of that of distilled water
   D. All the above

8. Pick up the correct statement from the following ?

   A. Turbidity is more in strong sewage
   B. The black colour indicates septic sewage
   C. The sewage omits offensive odours after four hours
   D. All the above

9. Pick up the correct statement from the following?

   A. The boning rod is used for checking the levels of the sewer inverts
   B. Manhole covers are made circular for the convenience of the cleaning staff
   C. A manhole is classified as shallow manhole if its depth is less than 0.9 m
   D. All the above

10. Pick up the correct statement from the following?

    A. pH value indicates acidity and alkalinity of sewage
    B. In acidic sewage, the pH value is less than 7
    C. In alkaline sewage, the pH value is more than 7
    D. All the above