Used by hi-fi buffs to measure the purity of copper cables and interconnects. The N stands for "nine".
A cable described as being made from 4N copper is at least 99.99% pure, since there are four nines in the percentage figure. I don't know if I could tell the difference between a 4N and a 5N cable just by listening, though.
See also Reliability Nines for a similar useage.
n is the first, or principal quantum number. This quantum number represents which energy level an electron can be found in. It is the first number in electron configurations: i.e. the 1 in 1s2.
N /N/ quant.
1. A large and indeterminate number of objects: "There were N bugs in that crock!" Also used in its original sense of a variable name: "This crock has N bugs, as N goes to infinity." (The true number of bugs is always at least N + 1; see Lubarsky's Law of Cybernetic Entomology.) 2. A variable whose value is inherited from the current context. For example, when a meal is being ordered at a restaurant, N may be understood to mean however many people there are at the table. From the remark "We'd like to order N wonton soups and a family dinner for N - 1" you can deduce that one person at the table wants to eat only soup, even though you don't know how many people there are (see great-wall). 3. `Nth': adj. The ordinal counterpart of N, senses 1 and 2. "Now for the Nth and last time..." In the specific context "Nth-year grad student", N is generally assumed to be at least 4, and is usually 5 or more (see tenured graduate student). See also random numbers, two-to-the-N.
--The Jargon File version 4.3.1, ed. ESR, autonoded by rescdsk.
N (en),
the fourteenth letter of English alphabet, is a vocal consonent, and, in allusion to its mode of formation, is called the dentinasal or linguanasal consonent. Its commoner sound is that heard in ran, done; but when immediately followed in the same word by the sound of g hard or k (as in single, sink, conquer), it usually represents the same sound as the digraph ng in sing, bring, etc. This is a simple but related sound, and is called the gutturo-nasal consonent. See Guide to Pronunciation, §§ 243-246.
The letter N came into English through the Latin and Greek from the Phenician, which probably derived it from the Egyptian as the ultimate origin. It is etymologically most closely related to M. See M.
© Webster 1913.
N, n. Print.
A measure of space equal to half an M (or em); an en.
printable version chaos
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