The maximum average depth due to one day storm over an area of 100 km2 is 100 mm. Depth-Area-Duration (DAD. curves indicate that for the same area of 100 km2 the maximum average depth for a 3 hour storm will be__________________?

Related Mcqs:

1. For a catchment area of 120 km2, the equilibrium discharge in m3/hour of an S-curve obtained by the summation of 6 hour unit hydro graph is_______________?

   A. 0.2 x 106
   B. 0.6 x 106
   C. 2.4 xlO6
   D. 7.2 xlO6

2. The normal annual precipitation at stations X, A, B and C are 700 mm, 1000 mm, 900 mm and 800 mm respectively. If the storm precipitation at three station A, B and C were 100 mm, 90 mm and 80 mm respectively, then the storm precipitation for station X will be___________________?

   A. 70mm
   B. 80mm
   C. 90 mm
   D. 105 mm

3. The area between the isohyets 45 cm and 55 cm is 100 square km and between 55 cm and 65 cm is 150 square km. The average depth of annua! precipitation over the above basin of 250 square km will be__________________?

   A. 50 cm
   B. 55 cm
   C. 56 cm
   D. 60 cm

4. The best unit duration of storm for a unit hydrograph is________________?

   A. 1 hour
   B. one-fourth of basin lag
   C. one-half of basin lag
   D. equal to basin lag

5. The peak of a 4 hour flood hydrograph is 240 m3/sec . If the rainfall excess is 80 mm and base flow which is constant is 40 m3/sec, then the peak of 4-hours unit hydrograph will be__________________?

   A. 20 3/sec
   B. 25 m3/sec
   C. 30 m3/sec
   D. 35 m3/sec

6. The rainfall on five successive days were measured as 100 mm, 80 mm, 60 mm, 40 mm and 20 mm respectively. If the infiltration index or the storm loss rate for the catchment area is earlier estimated as 50 mm/day, the total surface run off will be________________?

   A. 50 mm
   B. 60 mm
   C. 90 mm
   D. 140 mm

7. The maximum rainfall depth of 300 mm in 24 hours has a return period of 100 years. The probability of 24 hours rainfall equal to or greater than 300 mm occurring at least once in 10 years is given by_____________?

   A. (0.99)10
   B. 1 – (0.99)10
   C. (0.9)’00
   D. l-(0.9)100

8. The unit hydrograph due to a storm may be obtained by dividing the ordinates of the direct runoff hydrograph by_______________?

   A. direct runoff volume
   B. period of storm
   C. total rainfall
   D. none of the above

9. A 6 hours storm had 4 cm of rainfall and the resulting runoff was 2 cm. If <j) index remains at the same value, the runoff due to 10 cm of rainfall in 12 hours in the catchment is___________________?

   A. 4.5 cm
   B. 6.0 cm
   C. 7.5 cm
   D. 9.0 cm

10. If the risk of a flood occurring in the next 10 years is accepted to 10%, then the return period for design should be__________________?

    A. 1 + (0.9)010
    B. 1 – (0.9)°l0
    C. 1/(1-0.9°10)
    D. 1/(1+ 0.9010)