What method of wastewater treatment method involves removal of settle able solids and thickening of sludge’s?
a) sedimentation
b) floatation
c) filtration
d) microscreening
Answer:
The force on a surface “S” due to hydrostatic pressure is obtained by integration of the pressure over “S”, if “S” is plane. A single resultant point force can be found that is equivalent to the distributed pressure load. The magnitude of this resultant force maybe determined by F = PA, where A is the area of the surface and P is the pressure at the centroid of the surface, P is also the:
a) total pressure on the surface
b) resultant force on the surface
c) normal force on the surface
d) average pressure on the surface
Answer:
What method of wastewater treatment involves removal of fine residual suspended solids remaining after biological or chemical treatment?
a) filtration
b) sedimentation
c) floatation
d) microscreening
Solution:
Tow pipes connected in series having length and friction factor equal to each other. If the diameter of pipe 1 is twice the diameter of pipe 2, what is the ration of V1/V2?
Solution:
An open tank 1.82m. square, weighs 3425N and contains 0.91 m. of water. It is acted by an unbalanced force of 10400 N parallel to a pair of sides. What is the force (N) acting in the side with the greatest depth?
Solution:
The discharge flowing in a trapezoidal weir with its sides making an angle of 75°57’49” with the horizontal is 1.32 m3/s. If the head of water in the weir is 0.5 m, determine the length of crest.
Solution:
A tainter gate has a radius R, width W and height B. (B = 2R Sin θ, where 2θ from the hinge subtends B.) What is the horizontal force acting on the gate?
Solution:
The formula V = 1.318 C1 R0.63 S0.54 is known as:
a) Hazen Williams
b) Chezy’s formula
c) Manning’s formula
d) Cutters formula
Solution:
A trapezoidal canal having a base width of 1.8m. and a top width of 2.8m. is 1.2m. deep. If the normal flow is 17.857 m3/s at 1.2m. deep and coefficient of roughness n = 0.016, compute the hydraulic slope.
Solution:
Hydraulic jump occurs in a trapezoidal channel with sideslopes of 1:1 and base of 4m. If the upstream depth before the jump is 1.0m. and downstream depth is 2m., what is the discharge?
Solution:
In hydrology, depression storage is:
a) Water that penetrates into the soil and flows laterally in the surface soil.
b) Rain water collected by the leaves and stems of vegetation or structures.
c) Water retained as puddles
d) Nota
Solution:
What are the disadvantages of leaving vegetation within the reservoir?
a) Trees projecting above the water may create an undesirable presence.
b) trees will eventually float and create debris problem.
c) Decay of organic material may create undesirable odor and taste
d) All of the list
Solution:
In sewerage, micro screening is used to:
a) Filter residual solids that remain in water after setting.
b) Filter fine impurities such as algae
c) Remove particles such as silt, sand and flocculated suspensions
d) Nota
Solution:
Type of gate used for large installations.
a) Rolling gate
b) Tainter gate
c) Vertical lift gate
d) Nota
Solution:
A closed conduit with 25cm diam. is connected to a 20cm. diam. Pipe. If the velocity at the second pipe is 4 m/s, what is the velocity of the first pipe?
Solution:
A stream channel with perennial flow:
a) Effluent stream
b) Direct runoff
c) Influent stream
d) Nota
Solution:
A pressure gage at elevation 6m. at the side of the tank with liquid reads 90 kPa. Another gage at elevation 4m. reads 110 kPa. Compute the specific weight of the liquid.
Solution:
The jet of a horizontal nozzle strikes a vertical plate with a force equal to 7000N. If the discharge flowing at the nozzle is 0.12 m3/s. Compute the diameter of the jet.
Solution:
A tank filled with water to a depth of 2.4m. is accelerated upward at a rate of 3 m/s2. The velocity of the discharge at the orifice 2cm. in diameter located at the bottom of the tank is:
Solution:
A rectangular canal has a width of 2.75m. The flow passing thru the canal is 2.96 m3/s. and a velocity of 3.59 m/s. How high is the jump?
Solution:
A rectangular canal has a width of 2.5m. The flow passing thru the canal is 3.3 m3/s with a velocity of 3.78 m/s. How high is the jump?
Solution:
The average velocity in a pipe flowing full of incompressible liquid is 3 m/s. After passing through a conical section that reduces stream’s cross sectional area to ¼ of its previous value, the velocity after the conical section is:
Solution:
If water flows full in a trapezoidal canal having a base width of 1.8m., width at the top of 2.8m. and a depth of 1.2m., determine the type of flow. S = 0.002, n = 0.012.
Solution:
The head lost in an 80m. length of 12cm Ø pipe is 8m. When oil (sp.gr. = 0.90) of viscosity of 0.04 N.s/m2 flows at 0.05m3/s, determine the centerline velocity.
Solution:
Storm lasting 4 hours has 30 mm of rainfall, over an area of 800 hectares. Assuming zero base flow, what fraction of precipitation appeared as runoff?
Time(Hours) 0 1 2 3 4 5 6
Flow(m3/sec) 2 4 5 4 3 2 1
Solution:
A rectangular channel has a width of 3m. if the discharge flowing in the canal is 1.8 m3/s and coefficient of roughness n = 0.012, compute the critical slope.
Solution:
The length in a Cipolleti weir is 5 times its head. If the discharge flowing in the weir is 0.6 m3/s, compute the value of the head.
Solution:
An unbalanced vertical force of 270N upward accelerates a volume of 0.044 m3 of water. If the water is 0.9m. deep in a cylindrical tank, what is the force in N acting on the bottom of the tank?
Solution:
A water tank with diameter 3m. is filled with water. If the water level is 2m. above a nozzle and the nozzle is 5m. above the ground, how long will it take the water to hit the ground?
Solution:
For isentropic conditions:
a) pv = constant
b) pvn = constant
c) pvk = constant
d) none of these
Solution:
What is another term for a seepage line in a dam?
a) flownet
b) line of saturation or phreatic line
c) none of these
d) hydraulic line
Solution:
A rectangular timber flume, 2m. wide, discharges water at the rate of 1.2 cu.m/s. Determine the critical depth in m. Use g = 9.81.
Solution:
A 600 mm by 300 mm reducer connects two pipes. The velocity at the exit end of the reducer is 5 m/s and the pressure is 410 kPa. Neglecting secondary losses, find the resultant axial thrust of the water on the reducer in KN.
Solution:
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