1. Find: Daily Pumping Cost [$]Δh
$50
$100
$250
$500
fresh L s
Q=500
Find the daily pumping cost, in dollars. [pause] In this problem, ---
water
η = 70%
Δh = 30 [m]
energy
=$0.10 [kWh-1]
cost

2. Find: Daily Pumping Cost [$]Δh
$50
$100
$250
$500
fresh L s
Q=500
fresh water is pumped at 500 liters per second, from a lower reservoir to a higher reservoir.
water
η = 70%
Δh = 30 [m]
energy
=$0.10 [kWh-1]
cost

3. Find: Daily Pumping Cost [$]Δh
$50
$100
$250
$500
fresh L s
Q=500
The change in head, efficiency, and energy cost are provided in the problem statement. [pause] The daily pumping cost equals ----
water
η = 70%
Δh = 30 [m]
energy
=$0.10 [kWh-1]
cost

4. = Find: Daily Pumping Cost [$] * η = 70% fresh water Δh energy daily
used *
cost
cost
per day
fresh L s
Q=500
the energy used per day, multiplied by the cost of energy. The problem provides ---
water
η = 70%
Δh = 30 [m]
energy
=$0.10 [kWh-1]
cost

5. = Find: Daily Pumping Cost [$] * η = 70% fresh water Δh energy daily
used *
cost
cost
per day
fresh L s
Q=500
the cost of energy, as 10 cents per kilowatt-hour, so, we’re left to determine ---
water
η = 70%
Δh = 30 [m]
energy
=$0.10 [kWh-1]
cost

6. ? = Find: Daily Pumping Cost [$] * η = 70% fresh water Δh energy daily
used *
cost
cost
per day
fresh L s
Q=500
the energy used by the pump, for a duration of 1 day. [pause]
water
η = 70%
Δh = 30 [m]
energy
=$0.10 [kWh-1]
cost

7. ? Find: Daily Pumping Cost [$] η = 70% E=P * t fresh water energy Δh
used
per day
E=P * t
fresh L s
Q=500
Energy can be calculated as power times time, where we know ---
water
η = 70%
Δh = 30 [m]
energy
=$0.10 [kWh-1]
cost

8. ? Find: Daily Pumping Cost [$] η = 70% E=P * t fresh water energy Δh
used
per day
E=P * t
24 [hr]
fresh L s
Q=500
the time duration to be 1 day, or, 24 hours, ---
water
η = 70%
Δh = 30 [m]
energy
=$0.10 [kWh-1]
cost

9. ? Find: Daily Pumping Cost [$] η = 70% E=P * t fresh water
energy ? Δh
used
per day
E=P * t
24 [hr]
fresh L s
Q=500
and the power, in kilowatts, equals 9.81 times ----
water
9.81 * Δh * Q * SG P=
η = 70%
1,000 * η
Δh = 30 [m]
energy
[kW]
=$0.10 [kWh-1]
cost

10. ? Find: Daily Pumping Cost [$] η = 70% E=P * t fresh water
energy ? Δh
used
per day
E=P * t
24 [hr]
lift [m]
fresh L s
Q=500
the change in head, in meters, also referred to as the lift, times ---
water
9.81 * Δh * Q * SG P=
η = 70%
1,000 * η
Δh = 30 [m]
energy
[kW]
=$0.10 [kWh-1]
cost

11. ? Find: Daily Pumping Cost [$] η = 70% E=P * t fresh water
energy ? Δh
used
per day
E=P * t
24 [hr]
flowrate [l/s]
lift [m]
fresh L s
Q=500
the flowrate, in liters per second, times the ---
water
9.81 * Δh * Q * SG P=
η = 70%
1,000 * η
Δh = 30 [m]
energy
[kW]
=$0.10 [kWh-1]
cost

12. ? Find: Daily Pumping Cost [$] η = 70% E=P * t fresh water
energy ? Δh
used
per day
E=P * t
24 [hr]
flowrate [l/s]
lift [m]
fresh L s
Q=500
specific gravity of the fluid being pumped, all divided by ---
water
9.81 * Δh * Q * SG P=
η = 70%
1,000 * η
Δh = 30 [m]
energy
[kW]
specific
=$0.10 [kWh-1]
cost
gravity

13. ? Find: Daily Pumping Cost [$] η = 70% E=P * t fresh water
energy ? Δh
used
per day
E=P * t
24 [hr]
flowrate [l/s]
lift [m]
fresh L s
Q=500
1,000 times the efficiency, as a decimal. For this problem, we’re neglecting friction losses, since non are mentioned in the problem. Also, other pump power formulas ---
water
9.81 * Δh * Q * SG P=
η = 70%
1,000 * η
Δh = 30 [m]
energy
[kW]
specific
=$0.10 [kWh-1]
cost
gravity
efficiency

14. ? Find: Daily Pumping Cost [$] η = 70% E=P * t fresh water
energy ? Δh
used
per day
E=P * t
24 [hr]
flowrate [l/s]
lift [m]
fresh L s
Q=500
can be derived for different units than kilowatts, meters or liters per second, as are used in this equation. [pause] The values for ----
water
9.81 * Δh * Q * SG P=
η = 70%
1,000 * η
Δh = 30 [m]
energy
[kW]
specific
=$0.10 [kWh-1]
cost
gravity
efficiency

15. ? Find: Daily Pumping Cost [$] η = 70% E=P * t fresh water
energy ? Δh
used
per day
E=P * t
24 [hr]
fresh L
Q=500
lift, flowrate and efficiency are plugged into the equation, and the specific gravity of fresh water ---
water
9.81 * Δh * Q * SG s P=
η = 70%
1,000 * η
Δh = 30 [m]
energy
0.70
=$0.10 [kWh-1]
cost

16. ? Find: Daily Pumping Cost [$] η = 70% E=P * t fresh water
energy ? Δh
used
per day
E=P * t
24 [hr]
1.00
fresh L
Q=500
is 1, and is also plugged in. The power used by the pump ---
water
9.81 * Δh * Q * SG s P=
η = 70%
1,000 * η
Δh = 30 [m]
energy
0.70
=$0.10 [kWh-1]
cost

17. ? Find: Daily Pumping Cost [$] η = 70% E=P * t fresh water
energy ? Δh
used
per day
E=P * t
24 [hr]
1.00
fresh L
Q=500
equals kilowatts. [pause] Multiplying the power, ---
water
9.81 * Δh * Q * SG s P=
η = 70%
1,000 * η
Δh = 30 [m]
P=210.2 [kW]
energy
=$0.10 [kWh-1]
cost

18. ? Find: Daily Pumping Cost [$] η = 70% E=P * t fresh water
energy ? Δh
used
per day
E=P * t
24 [hr]
1.00
fresh L
Q=500
by 24 hours in a day, the energy used per day equals ---
water
9.81 * Δh * Q * SG s P=
η = 70%
1,000 * η
Δh = 30 [m]
P=210.2 [kW]
energy
=$0.10 [kWh-1]
cost

19. ? Find: Daily Pumping Cost [$] η = 70% E=P * t fresh water
energy ? Δh
used
per day
E=P * t
24 [hr]
1.00
fresh L
Q=500
5,045 kilowatt-hours. [pause]
water
9.81 * Δh * Q * SG s P=
η = 70%
1,000 * η
Δh = 30 [m]
P=210.2 [kW]
energy
=$0.10 [kWh-1]
cost
E=5,045 [kWh]

20. = Find: Daily Pumping Cost [$] * η = 70% fresh water Δh energy daily
used *
cost
cost
per day
fresh L
Q=500
The daily pumping costs can be found by multiplying ---
water s
η = 70%
Δh = 30 [m]
energy
=$0.10 [kWh-1]
cost
E=5,045 [kWh]

21. = Find: Daily Pumping Cost [$] * η = 70% fresh water Δh energy daily
used *
cost
cost
per day
fresh L
Q=500
the daily energy used, by the pump, in kilowatt-hours, by the -
water s
η = 70%
Δh = 30 [m]
energy
=$0.10 [kWh-1]
cost
E=5,045 [kWh]

22. = Find: Daily Pumping Cost [$] * η = 70% fresh water Δh energy daily
used *
cost
cost
per day
fresh L
Q=500
cost of energy, in dollars per kilowatt-hour, and the daily pumping cost equals, ---
water s
η = 70%
Δh = 30 [m]
energy
=$0.10 [kWh-1]
cost
E=5,045 [kWh]

23. = Find: Daily Pumping Cost [$] * η = 70% $505 fresh water Δh energy
used *
cost
cost
per day
fresh L
Q=500
$505 dollars. [pause]
water
$505 s
η = 70%
Δh = 30 [m]
energy
=$0.10 [kWh-1]
cost
E=5,045 [kWh]

24. = Find: Daily Pumping Cost [$] * η = 70% $505 $50 $100 $250 $500 fresh
energy
daily
energy =
pumping
used *
cost
cost
per day
fresh L
Q=500
Looking back at the possible solutions, ---
water
$505 s
η = 70%
Δh = 30 [m]
energy
=$0.10 [kWh-1]
cost
E=5,045 [kWh]

25. = Find: Daily Pumping Cost [$] * η = 70% $505 AnswerD $50 $100 $250
$500 Δh
energy
daily
energy =
pumping
used *
cost
cost
per day
fresh L
Q=500
the answer is D.
water
$505 s
η = 70%
Δh = 30 [m]
AnswerD
energy
=$0.10 [kWh-1]
cost
E=5,045 [kWh]

26. ? Index σ’v = Σ γ d γT=100 [lb/ft3] +γclay dclay 1
Find: σ’v at d = 30 feet
(1+wc)*γw
wc+(1/SG)
σ’v = Σ γ d d
Sand
10 ft
γT=100 [lb/ft3]
100 [lb/ft3]
10 [ft]
20 ft
Clay
= γsand dsand
+γclay dclay A W S
V [ft3]
W [lb]
40 ft
text
wc = 37% ? Δh
20 [ft]
(5 [cm])2 * π/4