1-80 Conversion and Equivalent Tables Table 1-24 provides the multiplying factors necessary to convert from one unit of measure to another and vice versa. Table 1-24.—Conversion Chart To Convert To Multiply By Conversely,   Multiply By Acres Square feet 4.356 x 10⁴ 2.296 10^-5 Acres Square meters 4047 2.471 10^-4 Ampere-hour Coulombs 3600 2.778 10^-4 Amperes Microamperes 1,000,000 0.000,001 Amperes Milliamperes 1,000 0.001 Amperes per sq cm Amperes per sq in 6.452 0.1550 Amperes-turns Gilberts 1.257 0.7958 Amperes-turns per  cm Amperes-turns per inch 2.540 0.3937 Amperes-turns per  cm Oersteds 1.257 0.7958 Ampere-turns per  in Oersteds 0.495 2.02 Ampere-turns per meter Oersteds .01257 79.58 Ampere-turns per weber Gilberts per maxwell 1.257 10^-8 7.958 10⁷ Atmospheres MM  of mercury at 0º C 760 1.316 10^-8 Atmospheres Feet  of water at 4º C 33.90 2.950 10^-2 Atmospheres Inches  of mercury at 0º C 29.92 3.342 10^-2 Atmospheres Kilograms  per sq meter 1.033 10⁴ 9.678 10^–5 Atmospheres Pounds per sq inch 14.70 6.804 10^-2 BTU Foot-pounds 778.3 1.285 10^-3 BTU Joules 1054.8 9.480   10^-4 BTU Kilogram-calories 0.2520 3.969 BTU per hour Horsepower-hours 3.929 10^–4 2545 Bushels Cubic feet 1.2445 0.8036 Celsius (Centigrade) deg Fahrenheit deg (º C 9/5) + 32 (º F - 32) 5/9 Circular Mils Sq centimeters 5.067 10^-6 1.973 10⁵ Circular mils Square mils 0.7854 1.273 Cubic feet Cords 7.8125 10^-3 128 Cubic feet Gallons (liquid US) 7.481 0.1337 Cubic feet Liters 28.32 3.531 10^-2 Cubic  inches Cubic centimeters 16.39 6.102 10^-2 Cubic  inches Cubic feet 5.787 10^-4 1728 Cubic inches Cubic meters 1.639 10^-5 6.102 10^-4 Cubic inches Gallons (liquid US) 4.329 10^-3 231 Cubic meters Cubic feet 35.31 2.832 10^-2 Cubic  meters Cubic yards 1.381 0.7646 Degrees  (angle) Radians 1.745 10^-2 57.30 Dynes Pounds 2.248 10^-6 4.448 10⁵ Ergs Foot-pounds 7.367 10^-8 1.356 10⁷ Fards Microtarads 1,000,000 0.000,001 Farads Picofarads 1,000,000,000,000 0.000,000,000,001 Fathoms Feet 6 0.16666