The water supply for a city is pumped to a distribution reservoir. The pumping rate is 600 cu.m. per 4 hours. The estimated requirements every 4 hours is shown below.
Hours Demand (cum)
0400 200
0800 800
1200 1100
1600 700
2000 500
2400 300
At 0800 hours the reservoir contains 700 cum, how much water is in the reservoir at 2000 hours?
Solution:
A spillway 2m. deep goes over a dam 40m. high. If Cw = 3.2, what is the velocity after the jump?
Solution:
Kinematics coefficient of viscosity is defined:
a) as the ratio of the mass density to the absolute viscosity
b) as the ratio of the absolute viscosity to the mass density
c) to be inversely proportional to the velocity
d) to directly proportional to the velocity
Solution:
A floating cylinder 10cm. in diameter and weighing 982 grams is placed in a cylindrical container 25cm. in a diameter partially full of water. The increase in the depth of water in the container due to placing the float in it is:
Solution:
This graphically presents the relationship for pipes among the dimensionless parameters friction factor f, Reynolds Number Re, and surface roughness e/D.
a) Chezy formula
b) Hazen-Williams formula
c) Moody diagram
d) Bernoulli equation
Solution:
The interface between immiscible fluid acts like an infinitely thin membrane that supports a tensile force. The magnitude of this force per unit length of a line on this surface is termed the coefficient of:
a) viscosity
b) hydrostatic tension
c) surface tension
d) capillary action
Solution:
Water jumps from a depth of 23cm. to 88cm. in an open rectangular channel 3.5m. wide. Find the discharge in cu.m/s. Use g = 9.81.
Solution:
What is the simplest device for measuring river stage:
a) weighing rain gage
b) staff gage
c) none of these
d) tipping bucket gage
Solution:
The ratio of the change in pressure to the relative change in density, and measures the compressibility of a material is known in fluid mechanics as:
a) compression ratio
b) bulk modulus of elasticity
c) modulus of volume
d) compression volume
Solution:
Pipes in parallel: Three pipes are parallely connected. The pipe characteristics are as follows:
Pipe D(cm) L(m) f
A 15 600 0.02
B 10 480 0.03
C 20 900 0.018
Find the rate flow in cu.m/s. in pipe A if the difference in head at ends is 40m.
Solution:
Biological wastewater treatment
a) rotating biological dis
b) activated sludge
c) all of these
d) trickling filter
Solution:
The discharge through a Cipolletti weir is 0.52 cu.m/s. The head on it is one-fourth of the crest’s length. What is the head in m.?
Solution:
A spillway 2m. deep goes over a dam 40m. high. If Cw = 3.2, what is the energy after jump?
Solution:
What is drainage structure which is NOT considered a cross drainage?
a) bridges
b) culvert
c) dips
d) none of these
Solution:
What are the methods for rainwater to reach a stream?
a) surface runoff
b) percolation
c) interflow
d) all of these
Solution:
An open rectangular channel discharges water at the rate of 4.5 cu.m/s at a depth of 32cm. The flume is 3.5m. wide. To what depth, in cm., can the water jump? Use g = 9.81.
Solution:
Which is NOT a chemical characteristics of water
a) alkalinity
b) pH level
c) total suspended and dissolved solids
d) dissolved cations and dissolved annions
Solution:
For a rectangular channel with depth 1.2m. and 1.8m. wide S = 0.002 and n = 0.012, what is the critical depth for this channel?
Solution:
For a rectangular channel with depth 1.2 m. and 1.8 m. wide S = 0.002 and n = 0.012, what would be the velocity of the flow?
Solution:
What occurs whenever the absolute pressure of a liquid is close to the vapor pressure?
a) upsurge
b) none of these
c) scouring
d) cavitation
Solution:
A turbine is to operate at 300 rpm under a net head of 400m. CV = 0.93. If a single 15cm. water jet is used, find the required pitch diameter of the wheel assuming phi = 0.45 and η = 0.85.
Solution:
Filtration of water is used to:
a) filter fine impurities such as algae, silt etc.
b) filter residual solids that remain in water after settling
c) none of these
d) remove particles such as silt, sand and flocculated suspensions
Solution:
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