Femtometers to Yards (fm to yd)

1 femtometer equals 1.093613298×10⁻¹⁵ yards (rounded).

1 femtometer = 1.093613298×10⁻¹⁵ yards

How to convert femtometers to yards

To convert femtometers to yards, multiply the number of femtometers by 1.093613298×10⁻¹⁵. The factor is rounded to 10 significant digits. To go the other way, multiply yards by 914,400,000,000,000.

yards = femtometers × 1.093613298×10⁻¹⁵

Example: 10 femtometers = 1.093613298×10⁻¹⁴ yards.

About these units

Femtometer (fm)

ScientificCurrent unit

One quadrillionth of a meter, also called a fermi. The scale of atomic nuclei; a proton is roughly 0.84 fm in radius.

Robert Hofstadter coined the nickname fermi for this length in a 1956 paper in Reviews of Modern Physics, honoring Enrico Fermi. The formal name comes from femto, which Wikipedia traces to the Danish and Norwegian word femten, meaning fifteen, a nod to the factor of 10 to the minus 15. The prefix entered the SI in 1964, and Hofstadter also used the term in his 1961 Nobel Lecture.

One femtometer is a quadrillionth of a meter, or 1,000 picometers. The unit suits atomic nuclei: Wikipedia gives a proton charge radius of about 0.841 fm and a gold nucleus radius of about 8.45 fm, so a heavy nucleus is roughly ten times wider than a proton. The 0.841 fm figure from that article is the one used here. Cross-sections in the same field are measured in barns, and one barn equals 100 square femtometers.

1 femtometer = 1×10⁻¹⁵ meters (exactly).

Sources: Wikipedia: Femtometre; Wikipedia: Metric prefix; NIST: metric (SI) prefixes

Yard (yd)

US & ImperialCurrent unit

3 feet or 36 inches, exactly 0.9144 meters. Used for sports fields, fabric and short distances in the US and UK.

Yard descends from the Old English gerd or gyrd, meaning a branch, stave or measuring rod. It first appears in the late seventh-century laws of Ine of Wessex, though there it names a tax unit, the yardland. Around 959 to 963 King Edgar ordered that the measure held at Winchester be used throughout his realm, the earliest record of a prototype. A story that Henry I fixed the yard as the distance from his nose to his thumb is later folklore, and the true origin, whether pace, cubit or waist, remains speculative.

Britain defined the Imperial Standard Yard in 1824 as the distance between two marks on a brass rod at 62 degrees Fahrenheit. A fire in 1834 damaged the standard, a replacement was made in 1845, and the Weights and Measures Act 1855 recognized it. The 1959 international agreement then fixed the yard at exactly 0.9144 meter. Today it measures American and Canadian football fields, association football pitches and cricket pitches, appears on UK road signs for short distances, and is still used to sell fabric in the US and UK.

1 yard = 0.9144 meters (exactly).

Sources: Wikipedia: Yard; Wikipedia: Inch; NIST Guide to the SI, Appendix B.8: conversion factors

Related conversions

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