23.

24,

26.

27.

28.

29.

30.

A rectangular open channel carries a flow of 2 m%/sec/m, what is the value of mihimum
specific energy?

(A) 0.74m (B) 1.11 प

(C) 148m (D) 1.85m

A hydraulic model of a spill way is constructed with a scale 1:25. If the prototype discharge is
3125 cumee, then the corresponding discharge for which the model should be tested is :

(4) 1 cumec (B) 2cumec
(C) 4cumec ൬൩൬) 8cumec

High COD to BOD ratio of an organic pollutant represents :
(A) High biodegradability of the pollutant
(8) Low biodegradability of the pollutant
(C) Presence of free oxygen for aerobic decomposition

(D) Presence of Toxic material in the pollutant

Which is a secondary air pollutant?
(൧) Photochemical smog (B) Sulphur dioxide
(C) Nitrogen dioxide (D) Dust particles

Isopleth is a line which joins all the points having :
(A) Equal depth of evapotranspiration (B) Equal depth of evaporation
(C) Equal depth of rainfall (D) Equal depth of infiltration

A flood discharge is to be estimated for design of a bridge across a river. If the designer
intends to accept 25% risk that a flood of that or higher magnitude will occur in the next
15 years, the return period that the designer must use in the estimation of flood discharge is :

(A) 53 years (B) 45 years
. (¢) 68 years ൩൬) 76 years

A waste water sample contains 106 mmoles/litre of hydroxyl ions at 25°C. The pH of the
sample is :

(A) 8.6 (8) 8.4

(0) 5.6 (0) 5.4

Faculative bacterias survive in :
(A) The presence of oxygen (B) The absence of oxygen
(Cy Both cases (A) and (B) (D) Neither (A) nor (B)

ھ۸ 6 155/2015