1. The observed value of the standard penetration number (N) at 10m depth of a siltysand deposit is 13. The unit weight of the soil is 16 kN/in 3.The N value after correcting for the presence of fines will be:

(A) 12

(B) 13

(C) 14

(D) 15

 

2.The force 'F' required at equilibrium on the semi-cylindrical gate shown below is:

• 9.81 kN
• 0.0 kN
• 19.62 kN
• none of the above

 

  3.Velocity distribution in a boundary layer flow over a plate is given by

(u/u m) = 1.5 h - 0.5 h 3 J

where, h = y/ d ; y is the distance measured normal to the plate; d is the boundary layer thickness; and U m is the maximum velocity at y = d . If the shear stress t , acting on the plate is given by

t =K( m u m)/ d

where, m is the dynamic viscosity of the fluid, K takes the value of:

• 0
• 1

(C) 1.5

(0) none of the above

 

  4.A 6-hour Unit Hydrograph (UH) of a catchment is triangular in shape with a total time base of 36 hours and a peak discharge of 18 m 3 /s. The area of the catchment (in sq. km) is:

 

• 233
• 117
• 1.2
• sufficient information not available

 

  5.When there is an increase in the atmospheric pressure, the water level in a well penetrating in a confined aquifer:

 

• increases
• decreases
• may increase or decrease depending on the nature of the-1fquifer
• does not undergo any change

 

  6.In a domestic wastewater sample, COD and BOD were measured. Generally which of the following statement is true for their relative magnitude?

 

• COD = BOD
• COD > BOD
• COD <BOD
• Nothing can be said

 

  7.In disinfection, which of the following forms of chlorine is most effective in killing the pathogenic bacteria?

 

• Cr
• OCI
• NH 2CI
• HOCI

 

  8.A Trickling filter is designed to remove:

 

• Settleable Solids
• Colloidal Solids
• Dissolved Organic Matter
• None of the above

 

  9.In natural water, hardness is mainly caused by:

 

• Ca ++ and Mn ++
• Ca ++ and Fe ++
• Na + and K +
• Ca ++ and Mg ++

  10.Bitumen is derived from:

• destructive distillation of coal tar
• destructive distillation of petroleum
• fractional distillation of petroleum
• naturally occurring ores

 
11. Dowel bars in concrete pavement are placed

  along the direction of traffic

• perpendicular to the direction of traffic
• along 45° to the direction of traffic
• can be placed along any direction

 

12. Stopping sight distance and frictional co-efficients are

 

• directly proportional to each other
• inversely proportional to each other
• unrelated
• either directly or inversely proportional to each other depending on the nature of pavement