UNIT CONVERSIONS
Key Concepts
•
Units are labels that distinguish one measurable quantity from other
measurable quantities
•
A given value divided by an equivalent value is equal to 1
•
Any number multiplied by 1 remains the same
•
By using equivalents, units can be changed to the desired units
•
Same units above and below the division line cancel each other out
Example A:
1 acre
= 1
2
43,560 ft
Example B:
87,120 ft2 x
1 acre
43,560 ft2
= 2 acres
Monorail Method of Converting Units
Step 1 – Draw a horizontal line with a vertical line in the middle of it
Step 2 – Write down your known number with appropriate units in the upper left space
Step 3 – Choose an appropriate equivalent and write in the next space
(make sure the value with the same units as your starting number is
below the line so that the units will cancel each other out)
Step 4 – Cross out units that appear above and below the division line
Step 5 – Do the math by multiplying your beginning number by all numbers
above the line and dividing by all numbers below the line
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UNIT CONVERSIONS
Example 1:
Convert 50 feet of head to psi.
Example 2:
Convert 100,000 ft2 to acres.
Example 3:
Convert 10 liters of water to pounds.
Example 4:
Convert 6 lb/day of polymer to mg/sec.
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UNIT CONVERSIONS
Convert between acres and square feet:
1 acre = 43,560 square feet
1. 150,000 square ft = _____________ acres
2. 23,000 square ft = _____________ acres
3. 500,000 square ft = _____________ acres
4. 5 acres = _____________ square feet
5. 3.5 acres = _____________ square feet
6. Find the acreage of a pond surface with an average width of 150 feet and a length
of 200 feet.
7.
Find the area in acres of a reservoir that is 1,000 feet long by 900 feet wide.
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UNIT CONVERSIONS
Convert the following volumes:
1 cubic foot of water = 7.48 gallons
8.
A basin that measures 20 ft wide by 40 ft long by 10 ft deep = _____________ gallons
9.
A basin that measures 20 ft wide by 30 ft long by 12 ft deep = _____________ gallons
10. A basin that measures 15 ft wide by 60 ft long by 13 ft deep = _____________ gallons
11. 250,000 gallons of water = _____________ cubic feet
12. 500,000 gallons of water = _____________ cubic feet
13. 150,000 gallons of water = _____________ cubic feet
14. 75,000 gallons of water = _____________ cubic feet
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© American Water College
UNIT CONVERSIONS
Convert the following volume/weight relationships:
1 gallon of water = 8.34 pounds
15. 1,500 gallons of water = _____________ pounds
16. 120,000 gallons of water = _____________ pounds
17. 50 gallons of water = _____________ pounds
18. 30,000 pounds of water = _____________ gallons
19. 5,000 pounds of water = _____________ gallons
Convert between English and Metric volumes:
1 gallon = 3.785 liters
20. 7 gallons = _____________ liters
21. 25 gallons = _____________ liters
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UNIT CONVERSIONS
22. 125 gallons = _____________ liters
23. 19 liters = _____________ gallons
24. 50 liters = _____________ gallons
Convert the following concentrations:
1 mg/L = 1 ppm
and 1% = 10,000 ppm
25. 5 ppm = _____________ mg/L
26. 58 mg/L = _____________ ppm
27. 5% = _____________ mg/L
28. 12.5% = _____________ mg/L
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UNIT CONVERSIONS
29. 5,000 mg/L = _____________ %
30. 90,000 mg/L = _____________ %
Convert between feet of Head and psi:
1 foot of water = 0.433 psi 1 psi = 2.31 feet of Head
31. 100 feet of water = _____________ psi
32. 525 feet of water = _____________ psi
33. 375 feet of water = _____________ psi
34. 55 psi = _____________ feet of head
35. 125 psi = _____________ feet of head
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© American Water College
UNIT CONVERSIONS
36. 250 psi = _____________ feet of head
Convert the following power relationships:
1 HP = .746 Kw = 550 ft-lb/sec = 33,000 ft-lb/min
37. 3 HP = _____________ Kw
38. 18 HP = _____________ Kw
39. 65 Kw = ____________ HP
40. 20 Kw = _____________ HP
41. 6,000 ft-lb/sec = _____________ HP
42. 17,000 ft-lb/sec = _____________ HP
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© American Water College
UNIT CONVERSIONS
43. 23,000 ft-lb/sec = _____________ Kw
44. 42,000 ft-lb/sec = _____________ Kw
Perform the following complex conversions:
45. 8 lb/day = _____________ mg/sec
46. 4 MGD = _____________ CFS (cubic feet per second)
47.
10 MG = ______________ acre-feet
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© American Water College
UNIT CONVERSIONS
1. 3.4 acres
2. 0.53 acres
3. 11.5 acres
4. 217,800 sq ft
5. 152,460 sq ft
6. 0.7 acres
7. 20.7 acres
8. 59,840 gallons
9. 53,856 gallons
10. 87,516 gallons
11. 33,422 cu ft
12. 66,845 cu ft
13. 20,053 cu ft
14. 10,027 cu ft
15. 12,510 lb
16. 1,000,800 lb
17. 417 lb
18. 3,597 gallons
19. 600 gallons
20. 26.5 L
21. 94.6 L
22. 473 L
23. 5 gallons
24. 13.2 gallons
25. 5 mg/L
26. 58 ppm
27. 50,000 mg/L
28. 125,000 mg/L
29. 0.5%
30. 9%
31. 43 psi
32. 227 psi
33. 162 psi
34. 127 ft of head
35. 289 ft of head
36. 577 ft of head
37. 2.2 Kw
38. 13.4 Kw
39. 87 HP
40. 26.8 HP
41. 10.9 HP
42. 30.9 HP
43. 31.2 Kw
44. 57 Kw
45. 42 mg/sec
46. 6.2 CFS
47. 30.7 acre-ft
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© American Water College