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SI units

the units of measurement generally accepted for all scientific and technical uses; together they make up the International System of Units. (See also metric system.) The abbreviation SI, from the French Système International d'Unités, is used in all languages. There are seven base SI units, defined by specified physical measurements, and two supplementary units. Units are derived for any other physical quantities by multiplication and division of the base and supplementary units. The derived units with special names are shown in the accompanying table.

SI is a coherent system. This means that units are always combined without conversion factors. The derived unit of velocity is the meter per second (m/s); the derived unit of volume is the cubic meter (m3). If you know that pressure is force per unit area, then you know that the SI unit of pressure (the pascal) is the unit of force divided by the unit of area and is therefore equal to 1 newton per square meter.

The metric prefixes can be attached to any unit in order to make a unit of a more convenient size. The symbol for the prefix is attached to the symbol for the unit, e.g., nanometer (nm) = 10−9 m. The units of mass are specified in terms of the gram, e.g., microgram (μg) = 10−9 kg.

Only one prefix is used with a unit; the use of units such as the millimicrometer is no longer acceptable. When a unit is raised to a power, the power applies to the prefix as well, e.g., a cubic millimeter (mm3) = 10−9 m3. When a prefix is used with a ratio unit, it should be in the numerator rather than in the denominator, e.g., kilometers/second (km/s) rather than meters/millisecond (m/ms). Only prefixes denoting powers of 103 are normally used. Hecto-, deka-, deci-, and centi- are usually attached only to the metric system units gram, meter, and liter.

Owing to the force of tradition, one noncoherent unit, the liter, equal to 10−3 m3, or 1 dm3, is generally accepted for use with SI. The internationally accepted abbreviation for liter is the letter l; however, this can be confused with the numeral 1, especially in typescript. For this reason, the capital letter L is also used as a symbol for liter. The lower case letter is generally used with prefixes, e.g., dl, ml, fl. The symbols for all other SI units begin with a capital letter if the unit is named after a person and with a lower case letter otherwise. The name of a unit is never capitalized.

li·ter (L, l),

(lē'tĕr), Although the SI unit of volume is the cubic meter and, by extension, the cubic centimeter (1 cm3=0.000 001 m3), the liter and its submultiples are preferred to the cubic meter and its submultiples for the expression of volumes and substance or mass concentrations in clinical chemistry. For practical purposes 1 cubic decimeter (dm3) = 1 liter (L). It recommended that capital (L) be used as the abbreviation of liter because the lowercase l can easily be misread as the numeral 1.
A measure of capacity of 1000 cubic centimeters or 1 cubic decimeter; equivalent to 1.056688 quarts (U.S., liquid).
[Fr., fr. G. litra, a pound]


(L) (lē'těr)
A measure of capacity of 1000 cubic centimeters or 1 cubic decimeter; equivalent to 1.056688 quarts (U.S., liquid).
Synonym(s): litre.
[Fr., fr. G. litra, a pound]


(L) (lē'těr)
A measure of capacity of 1000 cubic centimeters or 1 cubic decimeter; equivalent to 1.056688 quarts (U.S., liquid).
Synonym(s): litre.
[Fr., fr. G. litra, a pound]

Patient discussion about liter

Q. I need a Lyme LIterate Doctor in MA Moving to MA - son has chronic Lyme

A. Hi! Where are you moving to? I'm here in Boston with early Lyme that I hope is not going chronic (the treatment I've taken so far is only suppressing it, and it comes back if I stop antibiotics).

Apparently there is a Dr. Sam Donta who works in Falmouth and Boston: 508-539-6666. But he is pretty busy.

More discussions about liter
References in periodicals archive ?
iter, HSD by Rs5.02 per liter, SKO by Rs6.97 per liter and LDO by Rs6.95 per liter.
Prior to this, oil firms reduced gasoline prices by a range of P0.80 to P0.85 per liter, diesel prices by P0.60 to as much P0.65 per liter and kerosene, by P0.20 per liter.
A week before that, oil firms implemented a price rollback of P0.40 per liter for gasoline and P0.30 per liter for diesel.
Notification regarding new prices revealed that price of High Octane blended Component (HOBC) has been reduced by Rs 8.46 per liter. New price of HOBC will be Rs 123.57 as against of Rs 132.03 per liter.
At the start of the month, oil firms implemented a price increase of P0.50 per liter for gasoline, P0.30 per liter for diesel, and P0.80 per liter for kerosene.
The average net prices (prices without taxes and levies) for Eurosuper 95 in Austria are 0.514 euros per liter and in the EU average 0.525 euros per liter.
Those wanting the most can get a turbocharged 2.0-liter engine with a substantial 185 horsepower or a 2.5 liter 170-horse power V-6.
(The 760 and all 7-Series Volvos are gone '93 and the new front-drive 850 includes an odd inline five-cylinder engine.) New last year, this engine is an all-aluminum, inline ix cylinder, displacing 3.0 liters. It is a 24-valve design, with 201 horsepower and 197 foot-pounds of torque.
Astro Power Diesel, Astro Clean Diesel: -P2.00 per liter
Oil firms on Saturday cut pump prices of diesel by as much as 65 centavos per liter and of gasoline by 85 centavos per liter, ending a nine-week rally that raised prices by a total of as much as P5.60 a liter.
Oil firms will jack up prices of fuel products by about P1 per liter for the second week in a row amid rising tensions in the Middle East.
Use: laboratory diagnosis; consistency: powder; yeast extract 3 grams / liter; agar: 15 g / liter; sodium chloride: 5 g / liter; lactose: 10 grams / liter; dige,i agar digested casein and soy.