7.2.)7.9 Choosing SI prefixes The selection of the appropriate decimal multiple or submultiple of a unit for expressing the value of a quantity, and thus the choice of SI prefix, is governed by several factors.Tags: Essay On Democracy As A Form Of GovernmentResearch Paper On Autism Apa StyleA Short Essay On My FamilyResearch Paper On Transportation ProblemCreative Writing Tips For KidsBioethics Thesis StatementHomework Help High School ChemistryRandom Assignment MethodsBusiness Plan ScribdDifference Between Dissertation And Thesis
7.6 and 7.10.3.) a 10-kΩ resistor However, if there is any ambiguity, the words should be rearranged accordingly.
For example, the statement "the samples were placed in 22 m L vials" should be replaced with the statement "the samples were placed in vials of volume 22 m L." Expressing the values of time intervals and of plane angles are exceptions to this rule.
Also to avoid possible confusion, this strongly recommends that the word "to" be used to indicate a range of values for a quantity instead of a range dash (that is, a long hyphen) because the dash could be misinterpreted as a minus sign.
(The first of these recommendations once again recognizes that unit symbols are not like ordinary words or abbreviations but are mathematical entities—see Sec.
8.6.6); and "the amount-of-substance fraction is 0.15," or "the amount-of-substance fraction is 15 %," or " = 185 mmol/mol. For example, it would be acceptable to write "the fractional increase in the resistance of the 10 kΩ reference standard in 2006 was 0.002 %."7.10.3 ppm, ppb, and ppt In keeping with Ref.
[4: ISO 31-0], this takes the position that the language-dependent terms part per million, part per billion, and part per trillion, and their respective abbreviations "ppm," "ppb," and "ppt" (and similar terms and abbreviations), are not acceptable for use with the SI to express the values of quantities.4.2.1).7.10.1 Decimal multiples and submultiples of the unit one Because SI prefix symbols cannot be attached to the unit one (see Sec.6.2.6), powers of 10 are used to express decimal multiples and submultiples of the unit one.Instead, the letters or other symbols should be attached to the quantity.7.5 Unacceptability of mixing information with units When one gives the value of a quantity, any information concerning the quantity or its conditions of measurement must be presented in such a way as not to be associated with the unit.This means that quantities must be defined so that they can be expressed solely in acceptable units (including the unit one — see Sec. takes the position that the key elements of a scientific or technical paper, particularly the results of measurements and the values of quantities that influence the measurements, should be presented in a way that is as independent of language as possible.However, it is preferable to divide the degree decimally.Thus one should write 22.20° rather than 22°12′, except in fields such as cartography and astronomy.7.4 Unacceptability of attaching information to units When one gives the value of a quantity, it is incorrect to attach letters or other symbols to the unit in order to provide information about the quantity or its conditions of measurement.However, the values of quantities do not always allow this recommendation to be followed, nor is it mandatory to try to do so.In a table of values of the same kind of quantities or in a discussion of such values, it is usually recommended that only one prefix symbol should be used even if some of the numerical values are not between 0..For example, m = 3.6 when its value is expressed in the unit X—see Sec.7.1, note 2.)An alternative way of writing the above numerical value equation, and one that is preferred because of its simplicity and generality, is νt, where l is in meters, ν is in kilometers per hour, and t is in seconds." In fact, this form is still ambiguous because no clear distinction is made between a quantity and its numerical value.