furlongs (fur) to Mils (mil) conversion

What is the furlong?

The furlong (fur) is a unit of length in the imperial and US customary systems, equal to one-eighth of a mile, most commonly used today in horse racing.

Definition

One furlong equals 660 feet, or 220 yards, or 40 rods, or 10 chains.

$$1\ \text{fur} = 201.168\ \text{m}$$

Eight furlongs make one statute mile. This value uses the international foot; the US survey furlong is larger by a factor of 1200/1199.

Origin and History

The name comes from Old English "furh" (furrow) and "lang" (long), meaning the length of a furrow in a ploughed open field. In the medieval English system, a furlong was the distance a team of oxen could plough before resting, standardized as the long side of a one-acre strip (one furlong by one chain). It became a fundamental unit of the English land-measurement system.

Law and Notable Facts

The furlong survives chiefly in horse racing, where race distances are quoted in furlongs (for example, a "six-furlong sprint"). It is also preserved in the definition of the acre and the mile. The whimsical furlong–firkin–fortnight (FFF) system uses it as an example of an intentionally impractical unit of length.

Real-World Examples and Conversions

• 1 furlong = 220 yd = 660 ft = 201.168 m.
• 8 furlongs = 1 statute mile.
• 1 furlong = 10 chains = 40 rods.
• The Kentucky Derby is run over 10 furlongs (1.25 miles).

What is Mils?

Mils, also known as thou, is a unit of length commonly used in engineering and manufacturing, particularly in the United States. Understanding its definition and applications is crucial in various technical fields.

Definition of a Mil

A mil is defined as one thousandth of an inch. It is a small unit of length, often used when dealing with precise measurements.

$$1 \text{ mil} = \frac{1}{1000} \text{ inch} = 0.001 \text{ inch}$$

In metric units:

$$1 \text{ mil} = 0.0254 \text{ mm} = 25.4 \text{ μm}$$

Formation and Origin

The term "mil" is derived from "milli-inch," emphasizing its relationship to the inch. It was developed to simplify calculations and communication in industries where precision is paramount. Instead of dealing with fractions of an inch, engineers and manufacturers could use whole numbers of mils.

Applications of Mils

Mils are used extensively in various industries:

• Electronics: Measuring the thickness of wires, circuit boards, and coatings. For example, the thickness of the copper layer on a printed circuit board (PCB) might be specified in mils.
• Manufacturing: Specifying the thickness of plastic films, sheet metal, and other materials.
• Paper Industry: Indicating the thickness of paper and card stock.
• Coatings: Measuring the thickness of paint, varnish, and other protective layers on surfaces.

Real-World Examples in Other Quantities

While mil primarily measures length, it influences other quantities:

• Area: The cross-sectional area of wires is sometimes expressed in "circular mils" (CM), especially in electrical engineering. A circular mil is the area of a circle with a diameter of one mil.

  • $$A = d^2$$

  • Where $A$ is the area in circular mils and $d$ is the diameter in mils.
• Volume: Though less common, mil can be used to derive volume measurements when combined with other units.

Notable Associations

While no specific law or person is directly associated with the formal definition of a mil, its adoption and standardization have been driven by industry needs and engineering practices. Organizations like the American National Standards Institute (ANSI) contribute to defining and maintaining standards that include the use of mils.

Additional Resources

For more information about mils, you can refer to the following resources:

• Thousandth of an inch - Wikipedia
• Circular mil - Wikipedia