Origins of Measurements


No civilization can escape the need for a system of measurement. Before people had measuring tools, they found points of reference such as seeds, stones and their own limbs. Dividing things into units is an ancient task. Units of measurement were among the earliest tools invented by humans. Primitive societies needed rudimentary measures for many tasks: constructing dwellings of an appropriate size and shape, fashioning clothing, or bartering food or raw materials. An inch was accepted as the distance from the tip of the thumb to the first joint; a yard was the distance from the tip of a king's nose to the end of his middle finger; a fathom was the length of a Viking's embrace. As shown in ancient German woodcuts, the length of the rod was determined by measuring the total distance covered by the left feet of sixteen men, large and small.Here are four basic numeral systems of measure and the people who first used them. You'll recognize how they are still used today.


Numeral Systems
Binary
This Hindu unit divides things into halves, quarters, and eights. Modern computer programs are based on binary code.

Decimal
The Chinese and the Egyptians were the first to use decimals, which are tenths. The metric system is based on decimal units. The decimal system of writing numbers was introduced into Europe in the 1300's and is now widely used.

Duodecimal
The Romans used units of 12. Today we have 12 inches in a foot, 12 months in a year, 12 in a dozen.

Sexagesimal
The Babylonians used units of 60. Time is measured in 60s: 60 seconds in a minute, 60 minutes in an hour.


In ancient times, the body ruled when it came to measuring. The length of a foot, the width of a finger, and the distance of a step were all accepted measurements.

Inch
At first an inch was the width of a man's thumb. In the 14th century, King Edward II of
England ruled that 1 inch equal 3 grains of barley placed end to end lengthwise.

Hand
A hand was approximately 5 inches or 5 digits (fingers) across. Today, a hand is 4 inches and is used to measure horses (from the ground to the horse's withers, or shoulder).

Span
A span was the length of the hand stretched out, about 9 inches.

Foot
In ancient times, the foot was 111/42 inches. Today it is 12 inches, the length of the average man's foot.

Yard
A yard was originally the length of a man's belt or girdle, as it was called. In the 12th century, King Henry I of
England fixed the yard as the distance from his nose to the thumb of his out-stretched arm. Today it is 36 inches, about the distance from nose to out-stretched arm of a man.

Cubit
In ancient
Egypt, a cubit was the distance from the elbow to the fingertips. Today a cubit is 18 inches.

Lick
A Lick was used by the Greeks to measure the distance from the tip of the thumb to the tip of the index finger.

Pace
The ancient Roman soldiers marched in paces, which were the length of a double step, about 5 feet; 1,000 paces was a mile. Today, a pace is the length of one step, 21/2 to 3 feet.


Measurements


Near and Far

Metric Weights and Measures
Most of the world uses the metric system. The only countries not on this system are the U.S., Myanmar, and Liberia. The metric system is based on 10's. For example, 10 decimeters make a meter (39.37 inches).

Units smaller than a meter have Latin prefixes:


Units larger than a meter have Greek prefixes:


A millimicron is one thousandth of one millionth of one meter.


Helpful Hints:
Remember: A meter is a little more than a yard. A kilometer is less than a mile. A liter is a little more than a quart.

Length

Unit

Value

Kilometer (km)

1,000 Meters

Hectometer (hm)

100 Meters

Dekameter (dam)

10 Meters

Meter (m)

1 Meter

Decimeter (dm)

0.1 Meter

Centimeter (cm)

0.01 Meters

Millimeter (mm)

0.001 Meters

 

Capacity

Unit

Value

Kiloliter (kl)

1,000 Liters

Hectoliters (hl)

100 Liters

Dekaliters (dal)

10 Liters

Liter (l)

1 Liter*

Deciliter (dl)

0.10 Liters

Centiliter (cl)

0.01 Liters

Milliliter (ml)

0.001 Liters

* 1 liter + U.S. 1.057 quarts

 

Mass and Weight

Unit

Value

Metric Ton

1,000,000 Grams

Quintal (P)

100,000 Grams

Myriagram

10,000 Grams

Kilogram

1,000 Grams

Hectogram

100 Grams

Dekagram

10 Grams

Gram

1 Gram*

Decigram

0.10 Grams

Centigram

0.01 Grams

Milligrams

0.001 Grams

* 1 gram + U.S. 0.035 ounces


Metric Conversions

Multiply

By

To Find

Multiply

By

To Find

Centimeters

.0328

feet

Meters/minute

1.667

centimeters/second

Centimeters

.3937

inches

Meters/minute

.0547

feet/second

Feet

30.4801

centimeters

Miles

1.6093

kilometers

Feet/minutes

.507

cent./seconds

Miles/hour

.8684

knots

Foot-pounds

.1383

meter-kilograms

Miles/hour

1.6093

kilometers/hour

Gallons

3,785.4

cubic centimeters

Miles/hour

.447

meters/second

Gallons

3.7853

liters

Ounces

28.3495

grams

Grams

.0353

ounces

Ounces

2.8349x10(2)

kilograms

Grams

.0022

pounds

Pounds

453.5924

grams

Inches

2.54

centimeters

Pounds

.4536

kilograms

Inches

.0833

feet

Quarts

.946

liters

Kilograms

2.2046

pounds

Quarts (dry)

67.2

cubic inches

Kilometers

3,280.833

feet

Quarts (liquid)

57.75

cubic inches

Kilometers

.6214

miles

Sq. centimeters

.0011

square feet

Kilometers/hour

54.68

feet/minute

Sq. kilometers

.3861

square miles

Kilometers/hour

.6214

miles/hour

Sq. kilometers

1.196x10(6)

square yards

Knots

1.8532

kilometers/hour

Sq. meters

10.7639

square feet

Liters

1.0567

quarts

Sq. meters

1.196

square yards

Meters

3.2808

feet

Sq. miles

2.59

square kilometers

Meters

39.37

inches

Sq. yards

.8361

square meters

Meters

1.0936

yards

Yards

91.44

centimeters

Meter-kilograms

7.2307

foot-pounds

Yards

.9144

meters


The International System (Metric)
Source: Department of Commerce, National Bureau of Standards.
The International System of Units is a modernized version of the metric system, established by international agreement that provides a logical and interconnected framework for all measurements in science, industry, and commerce. The system is built on a foundation of seven basic units, and all other units are derived from them. (Use of metric weights and measures was legalized in the United States in 1866, and our customary units of weights and measures are defined in terms of the meter and kilogram.)

Length
Meter. Up until 1983, the meter was defined as 1,650,763.73 wavelengths in a vacuum of the orange-red line of the spectrum of krypton-86. Since then, it is equal to the distance traveled by light in a vacuum in 1/299,792,45 of a second.

Time
Second. The second is defined as the duration of 9,192,631,770 cycles of the radiation associated with a specified transition of the cesium-133 atom.

Mass
Kilogram. The standard for the kilogram is a cylinder of platinum-iridium alloy kept by the International Bureau of Weights and Measures at Paris. A duplicate at the National Bureau of Standards serves as the mass standard for the United States. The kilogram is the only base unit still defined by a physical object.

Temperature
Kelvin. The Kelvin is defined as the fraction 1/273.16 of the thermodynamic temperature of the triple point of water; that is, the point at which water forms an interface of solid, liquid, and vapor. This is defined as 0.01C on the Centigrade or Celsius scale and 32.02F on the Fahrenheit scale. The temperature 0K is called "absolute zero."

Electric Current
Ampere. The ampere is defined as that current that, if maintained in each of two long parallel wires separated by one meter in free space, would produce a force between the two wires (due to their magnetic fields) of 2 10-7 Newton for each meter of length. (A Newton is the unit of force that when applied to one kilogram mass would experience an acceleration of one meter per second per second.)

Luminous Intensity
Candela. The candela is defined as the luminous intensity of 1/600,000 of a square meter of a cavity at the temperature of freezing platinum (2,042K).

Amount of Substance
Mole. The mole is the amount of substance of a system that contains as many elementary entities as there are atoms in 0.012 kilogram of carbon-12.


Measuring Motion
Speed is the measure of motion. You can find it by dividing the distance covered by the time it takes to travel that distance.

Speed of Light
Light travels through space at 186,000 miles per second.
If a star is 10 light-years away, it is about 60 trillion miles distant.

Light-Year
A light ray travels 5.88 trillion miles a year in space.

Star Distance
The star Sirius is 9 light-years away from the solar system.

More Earthly Speeds


Measuring Power

Horsepower
A workhorse can lift 550 pounds 1 foot in the air in 1 second; that is 1 horsepower. Engines are measured in horsepower. A 10-horsepower engine can do the work of ten horses.

Manpower
An average man lifts 55 pounds 1 foot high in 1 second.

Candlepower
The amount of light given off by a candle of a specific size, shape, type of tallow, and type of wick. The brightness of an electric light is measured in candlepower.

Megaton
A megaton is the blasting power of a hydrogen bomb. One megaton has the power of 1 million tons of TNT.


Nautical Measurement
A fathom is 6 feet, the length of rope a man can extend from open arm to open arm. The rope was lowered into the sea to measure depth.

A cable length is the length of a ship's cable, about 600 feet.

A nautical mile is 10 cable lengths, or 6,080 feet.
1 nautical mile = 1.1515 miles

A knot is the measure of speed on water. One knot is 1 nautical mile per hour.


Miscellaneous Units of Measure
acre
An area of 43,560 square feet. Originally, the area a yoke of oxen could plow in one day.

agate
Originally a measurement of type size (5 and 1/2 points). Now equal to 1/14 inch. Used in printing for measuring column length.

ampere
Unit of electric current. A potential difference of one volt across a resistance of one ohm produces a current of one ampere.

astronomical unit (A.U.)
93,000,000 miles, the average distance of the earth from the sun. Used for astronomy.

bale
A large bundle of goods. In the U.S., the approximate weight of a bale of cotton is 500 pounds. The weight varies in other countries.

board foot (fbm)
144 cubic inches (12 in. 12 in. 1 in.). Used for lumber.

bolt
40 yards. Used for measuring cloth.

Btu
British thermal unit. Amount of heat needed to increase the temperature of one pound of water by one degree Fahrenheit (252 calories).

carat (c)
200 milligrams or 3.086 grains troy. Originally the weight of a seed of the carob tree in the Mediterranean region. Used for weighing precious stones.

chain (ch)
A chain 66 feet or one-tenth of a furlong in length, divided into 100 parts called links. One mile is equal to 80 chains. Used in surveying and sometimes called Gunter's or Surveyor's chain.

cubit
18 inches or 45.72 cm. Derived from distance between elbow and tip of middle finger.

decibel
Unit of relative loudness. One decibel is the smallest amount of change detectable by the human ear.

ell, English
1 and 1/4 yards or 1/32 bolt. Used for measuring cloth.

freight, ton (also called measurement ton)
40 cubic feet of merchandise. Used for cargo freight.

great gross
12 gross or 1728.

gross
12 dozen or 144.

hand
4 inches or 10.16 cm. Derived from the width of the hand. Used for measuring the height of horses at withers.

hertz
Modern unit for measurement of electromagnetic wave frequencies (equivalent to "cycles per second").

hogshead (hhd)
2 liquid barrels or 14,653 cubic inches.

horsepower
The power needed to lift 33,000 pounds a distance of one foot in one minute (about 1 and 1/2 times the power an average horse can exert). Used for measuring power of steam engines, etc.

karat (kt)
A measure of the purity of gold, indicating how many parts out of 24 are pure. For example: 18-karat gold is 3/4 pure. Sometimes spelled carat.

knot
Not a distance, but the rate of speed of one nautical mile per hour. Used for measuring speed of ships.

league
Rather indefinite and varying measure, but usually estimated at 3 miles in English-speaking countries.

light-year
5,880,000,000,000 miles, the distance light travels in a vacuum in a year at the rate of 186,281.7 miles (299,792 kilometers) per second. (If an astronomical unit were represented by one inch, a light-year would be represented by about one mile.) Used for measurements in interstellar space.

magnum
Two-quart bottle. Used for measuring wine, etc.

ohm
Unit of electrical resistance. A circuit in which a potential difference of one volt produces a current of one ampere has a resistance of one ohm.

parsec
Approximately 3.26 light-years or 3.08 1013 km (1.92 1013 mi). Term is combination of first syllables of parallax and second, and distance is that of imaginary star when lines drawn from it to both Earth and the Sun form a maximum angle or parallax of one second (1/3600 degree). Used for measuring interstellar distances.

pi ( pi )
3.14159265+. The ratio of the circumference of a circle to its diameter. For practical purposes, the value is used to four decimal places: 3.1416.

pica
1/6 inch or 12 points. Used in printing for measuring column width, etc.

pipe
2 hogsheads. Used for measuring wine and other liquids.

point
.013837 (approximately 1/72) inch or 1/12 pica. Used in printing for measuring type size.

quintal
100,000 grams or 220.46 pounds avoirdupois.

quire
Used for measuring paper. Sometimes 24 sheets but more often 25. There are 20 quires to a ream.

ream
Used for measuring paper. Sometimes 480 sheets, but more often 500 sheets.

roentgen
International Unit of radiation exposure produced by X-rays.

score
20 units.

sound, speed of
Usually placed at 1,088 ft. per second at 32F at sea level. It varies at other temperatures and in different media.

span
9 inches or 22.86 cm. Derived from the distance between the end of the thumb and the end of the little finger when both are outstretched.

square
100 square feet. Used in building.

stone
Legally 14 pounds avoirdupois in the U.K.

therm
100,000 BtU's.

township
U.S. land measurement of almost 36 square miles. The south border is 6 miles long. The east and west borders, also 6 miles long, follow the meridians, making the north border slightly less than 6 miles long. Used in surveying.

tun
252 gallons, but often larger. Used for measuring wine and other liquids.

watt
Unit of power. The power used by a current of one ampere across a potential difference of one volt equals one watt.


Standard Measurements in Sports:
http://www.factmonster.com/ipka/A0113430.html