Definition:FPS/Pound
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Definition
The pound is the FPS unit of measurement of mass, which has a number of different standards.
The most common standard is for it to be defined in kilograms to be exactly $0.453 \, 592 \, 37 \ \mathrm{kg}$.
Pound Avoirdupois
The pound is an avoirdupois unit of mass.
It is defined as being exactly $453 \cdotp 59237$ grams.
\(\ds \) | \(\) | \(\ds 1\) | pound avoirdupois | |||||||||||
\(\ds \) | \(=\) | \(\ds 16\) | ounces avoirdupois | |||||||||||
\(\ds \) | \(=\) | \(\ds 7 \, 000\) | grains | |||||||||||
\(\ds \) | \(=\) | \(\ds 453 \cdotp 59237\) | grams | \(\quad\) (exact) | ||||||||||
\(\ds \) | \(=\) | \(\ds 0 \cdotp 45359237\) | kilograms | \(\quad\) (exact) |
Apothecaries' Pound
The apothecaries' pound is an apothecaries' unit of mass.
\(\ds \) | \(\) | \(\ds 1\) | apothecaries' pound | |||||||||||
\(\ds \) | \(=\) | \(\ds 12\) | apothecaries' ounces | |||||||||||
\(\ds \) | \(=\) | \(\ds 5 \, 760\) | grains | |||||||||||
\(\ds \) | \(=\) | \(\ds 373 \cdotp 24\) | grams | |||||||||||
\(\ds \) | \(=\) | \(\ds 1\) | troy pound |
Troy Pound
\(\ds \) | \(\) | \(\ds 1\) | troy pound | |||||||||||
\(\ds \) | \(=\) | \(\ds 12\) | troy ounces | |||||||||||
\(\ds \) | \(=\) | \(\ds 5 \, 760\) | grains | |||||||||||
\(\ds \) | \(=\) | \(\ds 1\) | apothecaries' pound | |||||||||||
\(\ds \) | \(\approx\) | \(\ds 373 \cdotp 24\) | grams |
Libra (Roman Pound)
- $1$ libra $= 12$ unciae.
Its value in modern units is estimated to be approximately $5 \, 076$ grains or $329$ grams.
Symbol
- $\mathrm {lb}$
The symbol for the pound is $\mathrm {lb}$.
Its $\LaTeX$ code is \mathrm {lb}
.
This derives from the libra (Roman pound) from which the pound evolved.
It always needs to be distinguished from the pound sterling, whose symbol is $\pounds$.
Sources
- 1951: B. Hague: An Introduction to Vector Analysis (5th ed.) ... (previous) ... (next): Chapter $\text I$: Definitions. Elements of Vector Algebra: $1$. Scalar and Vector Quantities
- 1966: Isaac Asimov: Understanding Physics ... (previous) ... (next): $\text {I}$: Motion, Sound and Heat: Chapter $3$: The Laws of Motion: Mass