An unusual unit of measurement is a unit of measurement that does not form part of a coherent system of measurement; especially in that its exact quantity may not be well known or that it may be an inconvenient multiple or fraction of base units in such systems. This definition is deliberately not exact since it might seem to encompass units such as the week or the light-year which are quite "usual" in the sense they are often used; if they are used out of context, they may be "unusual," as demonstrated by the FFF system of units.
Unusual units of measure are sometimes used by scientists, especially physicists and mathematicians, and other technicians, engineers and computer programmers, either humorously or for real convenience when dealing with objects in the real world whose quantities in more conventional units may be awkward to use. Scientists studying nuclear reactions use the barn quite frequently; however, its use is extremely rare for other scientific disciplines. Unusual units are also employed by journalists and science instructors in an attempt to help people who may not be able to grasp extremely large or small numbers or unfamiliar scientific units. "An area the size of Denmark" and the banana equivalent dose are classic examples. Whether such comparisons actually are meaningful is open to debate, since the comparative quantity itself may not be well known with much accuracy. (e.g. What size and cultivar of the banana is the unit based on?)
Famous quotes containing the words list of, list, unusual, units and/or measurement:
“Religious literature has eminent examples, and if we run over our private list of poets, critics, philanthropists and philosophers, we shall find them infected with this dropsy and elephantiasis, which we ought to have tapped.”
—Ralph Waldo Emerson (1803–1882)
“A man’s interest in a single bluebird is worth more than a complete but dry list of the fauna and flora of a town.”
—Henry David Thoreau (1817–1862)
“Only in the most unusual cases is it useful to determine whether a book is good or bad; for it is just as rare for it to be one or the other. It is usually both.”
—Robert Musil (1880–1942)
“Even in harmonious families there is this double life: the group life, which is the one we can observe in our neighbour’s household, and, underneath, another—secret and passionate and intense—which is the real life that stamps the faces and gives character to the voices of our friends. Always in his mind each member of these social units is escaping, running away, trying to break the net which circumstances and his own affections have woven about him.”
—Willa Cather (1873–1947)
“That’s the great danger of sectarian opinions, they always accept the formulas of past events as useful for the measurement of future events and they never are, if you have high standards of accuracy.”
—John Dos Passos (1896–1970)