Why is liters a capital l

A liter is the volume of a cube with sides of 10 cm, which is slightly less than a cube of sides 4 inches or one-third of a foot. One liter is also slightly more than one U. A measured cup is roughly mL.

However, this number is usually rounded to mL to ease metrication of recipies using English units of measurement. Liters are most commonly used for items measured by the capacity or size of their container such as fluids and berries , whereas cubic meters and derived units are most commonly used for items measured either by their dimensions or their displacements. One liter of water has a mass of almost exactly one kilogram.

Similarly: 1 milliliter of water has about 1 g of mass; 1, liters of water has about 1, kg 1 ton of mass. This relationship is because the gram was originally defined as the mass of 1 mL of water.

However, this definition was abandoned in because the density of water changes with pressure and the units of pressure are dependent on the definition of mass. Originally, the only symbol for the liter was l lowercase letter l , following the SI convention that only those unit symbols that abbreviate the name of a person start with a capital letter. In many English-speaking countries, the most common shape of a handwritten Arabic digit 1 is just a vertical stroke, that is it lacks the upstroke added in many other cultures.

Therefore, the digit 1 may easily be confused with the letter l. On some typewriters, particularly older ones, the unshifted L key had to be used to type the numeral 1. Further, even in some computer typefaces, the two characters are barely distinguishable at all.

This caused some concern, especially in the medical community. As a result, L uppercase letter L was adopted as an alternative symbol for liter in The United States National Institute of Standards and Technology now recommends the use of the uppercase letter L, a practice that is also widely followed in Canada and Australia.

In the UK and Ireland, lowercase l is used with prefixes, though whole liters are often written in full so, " ml" on a wine bottle, but often "1 liter" on a juice carton.

This symbol can still be encountered occasionally in some English-speaking countries, and its use is ubiquitous in Japan and South Korea. Nevertheless, it is no longer used in most countries and no longer officially recognised by the Bureau International des Poids et Mesures, the International Organization for Standardization due to confusion and because it is often not anyway available in many documentation systems. The alternative symbol for the liter, L , was adopted by the CGPM in in order to avoid the risk of confusion between the letter l and the number 1.

Thus, although both l and L are internationally accepted symbols for the liter, to avoid this risk the preferred symbol for use in the United States is L. Neither a lowercase script letter l nor an uppercase script letter L are approved symbols for the liter. These units, which are subject to future review, should be defined in relation to the SI in every document in which they are used; their continued use is not encouraged.

Table 7. International SI style and usage publications focus on written communication. NIST SP provides an editorial checklist for reviewing manuscripts' conformity with the SI and the basic principles of physical quantities and units.

NIST guides use American spelling. All units and prefixes should be spelled as shown in this guide. Examples: meter, liter, and deka, NOT metre, litre, and deca. A space is used between the number and the symbol to which it refers. For example: 7 m, When a metric value is used as a one-thought modifier before a noun, hyphenating the quantity is not necessary. However, if a hyphen is used, write out the name of the metric quantity with the hyphen between the numeral and the quantity.

For example:. Spaces are not used between prefixes and unit names nor between prefix symbols and unit symbols. The dot or period is used as the decimal point within numbers. In numbers less than one, zero should be written before the decimal point.

Examples: 7. Some of the metric units listed above include prefixes such as kilo, centi, and milli. Prefixes, added to a unit name, create larger or smaller units by factors that are powers of