Cable Lengths to Millimeters (cb to mm)

1 cable length equals 185,200 millimeters exactly.

1 cable length = 185,200 millimeters

How to convert cable lengths to millimeters

To convert cable lengths to millimeters, multiply the number of cable lengths by 185,200. This factor is exact. To go the other way, multiply millimeters by 0.000005399568035 (rounded).

millimeters = cable lengths × 185,200

Example: 10 cable lengths = 1,852,000 millimeters.

About these units

Cable Length (cb)

NauticalTraditional unit (still used in some regions)

One tenth of a nautical mile (185.2 m). A traditional nautical measure for short distances between ships.

Before it became a figure on a chart, a cable was simply the thick rope that held a ship at anchor. Ropemakers worked on long covered ropewalks, and the length of the walk limited the longest rope they could lay. By the mid-sixteenth century the usual anchor cable was about 100 fathoms, or 600 feet, so the word turned into a measure of distance. The ropewalk at Chatham Dockyard is a quarter of a mile long, built to turn out standard coils of 120 fathoms.

Mariners found a cable handy for judging short gaps, such as the space between two ships in formation or the distance to a hazard. Because a nautical mile of 6,080 feet divides neatly by ten, the Admiralty tied the cable to a tenth of a sea mile, about 608 feet. The figure used here follows the international nautical mile of 1,852 m, giving 185.2 m. Other definitions differ: a traditional British cable of 100 fathoms is 182.9 m, while the older US Navy cable of 120 fathoms is about 219.5 m. Sources therefore span roughly 169 to 220 m.

1 cable length = 185.2 meters (exactly).

Sources: Wikipedia: Cable length; Wikipedia: Nautical mile

Millimeter (mm)

Metric (SI)Current unit

One thousandth of a meter. Used in engineering, manufacturing and rainfall measurement.

Carl Friedrich Gauss put the millimeter at the base of his 1832 proposal for absolute units, pairing it with the milligram and the second, although the centimeter-based CGS system later won out among scientists. The name combines the metric prefix milli-, from the Latin for one thousand, with the meter. Since 1983 a millimeter has been tied to the speed of light: it is the distance light covers in 1/299,792,458,000 of a second.

Millimeters are the language of fine mechanical work. Standard rulers are divided into them, digital calipers commonly read to 0.01 mm, and mechanical pencil leads come in 0.5 and 0.7 mm. Copy paper is about 0.1 mm thick, and a thin hair, at 0.02 to 0.04 mm across, is close to the smallest thing the naked eye can see. A wave with a frequency of 300 GHz has a wavelength of 1 mm. An inch is exactly 25.4 mm. One trap for readers in the United States is that mil there traditionally means a thousandth of an inch, not a millimeter.

1 millimeter = 0.001 meters (exactly).

Sources: Wikipedia: Millimetre; Wikipedia: Centimetre-gram-second system of units; NIST Guide to the SI, Appendix B.8: conversion factors

Related conversions

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