English
Españolvalues us
Useful Formulas
VALUES
TRIANGLE: A = ab / 2 (a = height, b = base): half the product of the base height
SQUARE: A = a2 (to one of the sides)
RECTANGLE: A = ab (at height, b base): product of the base height
TRAPECIO: A = a (b + c) / 2 (b longest side, c shortest side, at height): half the product of the height by the sum of the parallel sides
REGULAR PENTAGON: A = 1,720 a2 (to one of the squares)
REGULAR HEXAGON: A = 2,598 a2 (to one of the sides)
REGULAR OCTAGON: A = 4.828 a2 (to one of the sides)
CIRCLE: A = ¶R2 (¶ 3.14159, r radius)
SPHERICAL SURFACE: 4¶ r2, in other words 4 times the area of ??the circle.
PI (¶) is the ratio of the length of a circle to its diameter; its value with 14 decimals is 3.14159265358989; in practice, 3.14159 is used.
CIRCUMFERENCE: C = 2¶ r (¶ 3.14159, r radius) So the length of the circumference is equal to twice the radius (ie the diameter) for the reason ¶
CUBE: V = a3 (to one of the edges)
RECTANGULAR PRISM: V = abc (a length, b width, c depth)
PYRAMID: V = Ah / 3 (A area of ??the base, h height): third part of the product of the area of ??the base
CYLINDER: V = ¶r2h, that is, the area of ??the base (which is a circle) by the height (h)
CONE: V = ¶r2h / 3 a third of the base area by height (h)
SPHERE: V = 4¶r2 = / 3 (¶ 3.14159, radius r)
CONVERSION OF THE MATTER IN ENERGY: E = mc2 (E represents the energy in ergios, m the mass or matter in grams and c the speed of light in centimeters per second, or the figure of 30,000 million).
Conversion Factors
| To convert | in | Multiply by | To Convert | in | Multiply by |
|---|---|---|---|---|---|
| Acres | Hectares | 0,4047 | Square meter | Square feet | 10,7639 |
| Bushels | Hectoliters | 0,3524 | Square meter | Square Yards | 1.1960 |
| Centimeters | Inches | 0,3937 | Cubic meters | Cubic feet | 35,3145 |
| Square Centimeters | Square Inches | 0,1550 | Cubic meters | Cubic Yards | 1,3079 |
| Cubic centimeters | Cubed Inches | 0,0610 | Millimeters | Inches | 0,0394 |
| American gallons | Liters | 3,7853 | Miles | Kilometers | 1,6093 |
| Grams | Grain | 15,4224 | Ounces | Grams | 28,3495 |
| Grams | Ounces | 0,0353 | Feet | Meters | 0,3048 |
| Grams | Grams | 0,0648 | Square feet | Square meter | 0,0929 |
| Hectaries | Acres | 2,4710 | Cubic feet | Cubic meters | 0,0283 |
| Hectoliters | Bushels | 2,8378 | Inches | Millimeters | 25,4001 |
| Kilograms | Pounds (av.) | 2,2046 | Inches | Centimeters | 2,5400 |
| Kilograms | Troy pounds | 2,6792 | Square Inches | Square Centimeters | 6,4516 |
| Kilometers | Miles | 0,6214 | Cubed Inches | Cubic centimeters | 16,3872 |
| Pounds (av.) | Kilograms | 0,4563 | Pintas (Arid) | Liters | 0,5506 |
| Troy pounds | Kilograms | 0,3732 | Pints (Liquid) | Liters | 0,4732 |
| Liters | American Gallons | 0,2642 | American Tons | Metric Tons | 0,9072 |
| Liters | Pintas (Arid) | 1,8162 | English Tons | Metric Tons | 1,0160 |
| Liters | Pints (Liquid) | 2,1134 | Metric Tons | American Tons | 1,1023 |
| Liters | Quarts (Arid) | 0,9081 | Metric Tons | English Tons | 0,9842 |
| Liters | Quarts (Liquids) | 1,0567 | Yards | Meters | 0,9144 |
| Meters | Feet | 3,2808 | Square Yards | Square meter | 0,8361 |
| Meters | Yards | 1,0936 | Cubic yards | Cubic meters | 0,7646 |
Wire Gauge Conversion
| B. W. G. | S. W. G. | A. S. W. | CALIBER WIRE NUMBER | B. W. G. | S. W. G. | |
|---|---|---|---|---|---|---|
| 3/0 | 10,79 | 9,45 | 9,21 | 15 | 1,83 | 1,83 |
| 2/0 | 9,65 | 8,48 | 8,41 | 16 | 1,65 | 1,625 |
| 1/0 | 8,68 | 8,23 | 7,78 | 17 | 1,47 | 1,422 |
| 1 | 7,62 | 7,62 | 7,19 | 18 | 1,24 | 1,219 |
| 2 | 7,21 | 7,01 | 6,67 | 19 | 1,07 | 1,016 |
| 3 | 6,58 | 6,40 | 6,19 | 20 | 0,89 | 0,914 |
| 4 | 6,04 | 5,89 | 5,72 | 21 | 0,81 | 0,813 |
| 5 | 5,59 | 5,38 | 5,26 | 22 | 0,71 | 0,711 |
| 6 | 5,16 | 4,88 | 4,88 | 23 | 0,63 | 0,610 |
| 7 | 4,57 | 4,47 | 4,50 | 24 | 0,56 | 0,559 |
| 8 | 4,19 | 4,06 | 4,11 | 25 | 0,51 | 0,508 |
| 9 | 3,76 | 3,66 | 3,77 | 26 | 0,46 | 0,457 |
| 10 | 3,40 | 3,25 | 3,43 | 27 | 0,41 | 0,417 |
| 11 | 3,05 | 2,95 | 3,06 | 28 | 0,36 | 0,376 |
| 12 | 2,77 | 2,64 | 2,68 | 29 | 0,33 | 0,345 |
| 13 | 2,41 | 2,34 | 2,32 | 30 | 0,305 | 0,315 |
| 14 | 2,11 | 2,03 | 2,03 |
Weights and Measures (Metric System)
WEIGHTS AND MEASUREMENTS, METRIC SYSTEM
The metric system is the one used in most civilized countries. Its fundamental units are: for lengths the meter; for weights the gram; and for capacities the liter. The square meter is used to measure the surfaces, and the cubic meter to measure the volumes.
The derived units are multiples or sub multiples of the fundamental ones. Each one is worth ten of the immediately inferior ones. The multiples are formed, prefixing the name of the fundamental unit, the Greek voices: deca, which means 10; hecto, 100; kilo, 1000; myria, 10,000; putting the Latin voices first: deci, which means tenth; centi, hundredth; and mili, thousandth. Today the micro particle is also used, which means millionth.
LENGTH STOCKINGS
The meter is equivalent to 1,650,763.73 wavelengths of the red-orange ray emitted in a vacuum by a crypton-86 gas atom. At first, the meter was intended to be a ten-millionth part of the quadrant of the terrestrial meridian, but this definition was abandoned because of the difficulty of making such a measurement with absolute precision. Then the international prototype meter was kept (until 1960) in a platinum bar and kept at a temperature of 0 ° C.
| 1 | myriameter (Mm.) | 10.000 | meters | |
| 1 | kilometer (Km.) | 1.000 | “ | |
| 1 | hectometer (hm.) | 100 | “ | |
| 1 | decameter (Dm.) | 10 | “ | |
| 1 | meter (m.) | 1 | “ | |
| 1 | decimeter (dm.) | 0,1 | “ | |
| 1 | centimeter (cm.) | 0,01 | “ | |
| 1 | millimeter (mm.) | 0,001 | “ | |
| 1 | micron (or micromillimeter) | 0,000.001 | “ | 0,000.1 mm. |
| 1 | millimicra (or millimicron) | 0,000.000.001 | 0,001 micra | |
| 1 | angstrom (A.) | 0,000.000.1 mm. | 0,000.1 micra | 0,1 milimicra |
SURFACE MEASURES
| 1 | square diameter (Mm2) | 100.000.000 m2 |
| 1 | square kilometer (km2) | 1.000.000 m2 |
| 1 | hectare (Ha.) or square hectoliter (hm2) | 10.000 m2 |
| 1 | area (a.) or square decameter (Dm2) | 100 m2 |
| 1 | square meter (m2) | 1 m2 |
| 1 | square decimeter (dm2) | 0,01 m2 |
| 1 | square centimeter (cm2) | 0,000.1 m2 |
| 1 | square millimeter (mm2) | 0,000.001 m2 |
VOLUME MEASURES
| 1 | cubic kilometer (km3) | 1.000.000.000 m3 |
| 1 | cubic hectoliter (hm3) | 1.000.000 m3 |
| 1 | cubic decimeter (Dm3) | 1.000 m3 |
| 1 | cubic meter (m3) or stereo | 1 m3 |
| 1 | cubic decimeter (dm3) | 0,000.1 m3 |
| 1 | cubic centimeter (cm3) | 0,000.001 m3 |
| 1 | cubic millimeter (mm3) | 0,000.000.001 m3 |
WEIGHT MEASUREMENTS
The gram is one thousandth of the international prototype kilogram. Platinum and iridium cylinder that is kept in the international office of weights and measures, in France. The gram is almost exactly equal to the weight of a cubic centimeter of pure water at 4 ° C of temperature, at sea level.
| 1 | metric ton (T) | 1.000 kg. | |
| 1 | quintal metric (q) | 100 kg. | |
| 1 | milligram (Mg) | 10 kg. | |
| 1 | kilogram (kg) | 1 kg. | 1.000 g. |
| 1 | hectogram (hg) | 100 g. | |
| 1 | decagram (Dg) | 10 g. | |
| 1 | gram (g) | 1g. | |
| 1 | decigram (dg) | 0,1 g. | |
| 1 | centigram (cg) | 0,01 g. | |
| 1 | milligram (mg) | 0,001 g. | |
| 1 | metric kilate | 200 mg. | 0,2 g. |
CAPACITY MEASURES
| 1 | kiloliter (kl) | 1.000 liters | 1 m3 |
| 1 | hectoliter (hl) | 100 liters | |
| 1 | decalitro (Dl) | 10 liters | |
| 1 | liter (l) | 1 liter | 1 dm3 |
| 1 | deciliter (dl) | 0,1 | |
| 1 | centiliter (cl) | 0,01 | |
| 1 | milliliter (ml) | 0,001 |