Measurements, Conversions, and Formulas

area calculations

volume calculations

volume calculations for structures


Important Formulas:

gallons per minute formula

gallons per minute formula

gallons per minute formula

gallons per acre formula

gallons per thousand square feet formula

gallons per minute formula based on ounces per minute

miles per hour formula

GPM =  gallons per minute
GPA =  gallons per acre
OPM =  ounces per minute
MPH =  miles per hour
W =  Nozzle spacing (in inches) for broadcast spraying
=  Spray width (in inches) for single nozzle
=  Band width (in inches) divided by the number of nozzles per band
=  Row spacing (in inches) divided by the number of nozzles per row for directed crop foliar spraying
5,940 = a constant used to convert GPM, MPH, and inches to GPA
136 =  a constant used to convert GPM, MPH, and inches to gal / 1,000 sq ft.

 


Percentage Mixing: To determine the amount of pesticide needed to make a solution (or suspension) containing a certain percentage of the active ingredient (a.i.), use one of the following formulas:

For emulsifiable concentrates and other liquid formulations–

number of gallons emulsifiable concentrates needed formula

For wettable powder formulations–

number of pounds wettable powder needed formula


Dairyman’s Square: To create a solution of specific concentration from two solutions of different concentrations or strengths–

dairyman's square formula


Ground Speed Chart

Speed  Time required in seconds to cover course distance
MPH 100 ft 200 ft 300 ft
1.0 68 136 205
1.5 45 91 136
2.0 34 68 102
2.5 27 54 81
3.0 23 45 68
3.5 20 39 58
4.0 17 34 51
4.5 15 30 45
5.0 14 27 41
5.5 x 25 37
6.0 x 23 34
6.5 x 21 31
7.0 x 19 29
7.5 x 18 27
8.0 x 17 26
8.5 x 16 24
9.0 x 15 23

x = not recommended

miles per hour formula


Common Conversion Factors

Multiply… by… to get…
Acres 43,560 Square feet
4,840 Square yards
4,047 Square meters
0.4047 Hectares
Centimeters 0.394 Inches
0.0328 Feet
0.01 Meters
10 Millimeters
Cubic centimeters 0.06102 Cubic inches
1 Milliliter
Cubic inches 16.39 Cubic centimeters
Cup 0.5 Pints
8 Fluid ounces
16 Tablespoons
Feet 12 Inches
304.8 Millimeters
30.48 Centimeters
0.3048 Meters
Gallons 4 Quarts
8 Pints
16 Cups
128 Fluid ounces
231 Cubic inches
3,785 Milliliters
3.785 Liters
Gallons of water 8.3453 Pounds of water
3.785 Kilograms of water
Gallons per acre 2.47 Gallons per hectare
9.35 Liters per hectare
Multiply… by… to get…
Grams 0.03527 Fluid ounces
1,000 Milligrams
0.001 Kilograms
Hectares 2.47 Acres
107,639 Square feet
10,000 Square meters
Inches 25.4 Millimeters
2.54 Centimeters
Kilograms 1,000 Grams
35.274 Ounces (dry)
2.205 Pounds
Kilograms per hectare 0.89 Pounds per acre
Kilometers 3,280.8 Feet
1,093.6 Yards
0.6214 Miles
1,000 Meters
Liters 1,000 Milliliters
33.8 Fluid ounces
61.02 Cubic inches
2.113 Pints
1.057 Quarts
0.264 Gallons
Meters 39.37 Inches
3.281 Feet
1.094 Yards
100 Centimeters
0.001 Kilometers
1,000 Millimeters
Miles 1,760 Yards
5,280 Feet
1,609 Meters
1.609 Kilometers
Multiply… by… to get…
Miles per hour 88 Feet per minute
1.609 Kilometers per hour
Milliliters 0.0338 Fluid ounces
0.06 Cubic inches
1 Cubic centimeter
Millimeters 0.0394 Inches
0.1 Centimeters
Ounces (dry) 0.0625 Pounds
28.35 Grams
Ounces (liquid) 0.125 Cups
2 Tablespoons
6 Teaspoons
0.0078125 Gallons
29.57 Milliliters
0.02957 Liters
Parts per million 0.0001 Percent (%)
1 Milligram per liter
1 Milligram per kilogram
Percent (%) 10,000 Parts per million
Pints (liquid) 2 Cups
16 Fluid ounces
0.125 Gallons
473 Milliliters
0.473 Liters
Pounds 16 Ounces
453.6 Grams
0.4536 Kilograms
Pounds per acre 1.12 Kilograms per hectare
Quarts (liquid) 2 Pints
4 Cups
32 Fluid ounces
946 Milliliters
0.946 Liters
Multiply… by… to get…
Square centimeters 0.155 Square inches
Square feet 144 Square inches
929 Square centimeters
0.0000229 Acres
0.00000929 Hectares
Square inches 0.007 Square feet
6.45 Square centimeters
Square kilometers 247.1 Acres
0.386 Square miles
100 Hectares
Square meters 1,550 Square inches
10.76 Square feet
1.196 Square yards
Square miles 640 Acres
259 Hectares
Square yards 1,296 Square inches
9 Square feet
8,361 Square centimeters
0.8361 Square meters
Tablespoons 0.5 Fluid ounces
3 Teaspoons
0.0625 Cups
14.8 Milliliters
Teaspoons 0.17 Fluid ounces
4.9 Milliliters
Ton (US) 2,000 Pounds
907.2 Kilograms
Ton (metric) 2,204.6 Pounds
1,000 Kilograms
Yards 3 Feet
36 Inches
0.914 Meters

Miscellaneous Weights and Measures:

1 acre-inch of water = 27,154.2 gal

1 inch of water per 1,000 sq ft = 623.4 gal

1 milliliter or cubic centimeter of water weighs 1 gram

1 liter of water weighs 1 kilogram

1 gallon of water weighs 8.3453 pounds

1 gallon of water weighs 3.785 kilograms


Row Crop Calculations:

Calculation for row-feet per acre

Rows per acre calculation


 

Aquatic Measures and Formulas:

1 Cubic foot = 62.4 Pounds of water

1 Cubic foot = 7.4805 Gallons

1 Part per million (PPM) = 2.7181 Pounds per acre-foot of water

Acre-feet = Average depth (ft) × Surface area (acres)

Herbicide needed (pounds a.i.) = PPM × Acre-feet × 2.7

part per million formula

surface area of a pond formula


Temperature Conversion:

To convert Celsius (oC) to Fahrenheit (oF): multiply by 1.8 and add 32

To convert Fahrenheit (oF) to Celsius (oC): subtract 32 and multiply by 0.56

Temperature Conversion
ºC ºF
100 212
95 203
90 194
80 185
75 176
70 160
65 150
60 140
55 130
50 122
45 113
40 104
35 95
30 86
25 77
20 68
15 60
10 50
5 41
0 32
-5 29
-10 14
-15 5
-20 -4
-25 -13
-30 -22
-35 -31
-40 -40

 

Compiled by Wayne Buhler, PhD.

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