|
Rho
Rho (; uppercase Ρ, lowercase ρ or ; or ) is the seventeenth letter of the Greek alphabet. In the system of Greek numerals it has a value of 100. It is derived from Phoenician alphabet, Phoenician letter resh . Its uppercase form uses the same glyph, Ρ, as the distinct Latin alphabet, Latin letter P; the two letters have #Character encodings, different Unicode encodings. Uses Greek Rho is classed as a liquid consonant (together with Lambda (letter), Lambda and sometimes the nasals Mu (letter), Mu and Nu (letter), Nu), which has important implications for Morphology (linguistics), morphology. In both Ancient Greek, Ancient and Modern Greek, it represents an alveolar trill , alveolar tap , or alveolar approximant . In polytonic orthography, a rho at the beginning of a word is almost always written ⟨⟩ (''rh'') with a rough breathing mark, indicating that it is voiceless consonant, voiceless. Very rarely, it is written ⟨⟩ (''r'') with a smooth breathing mark, indicatin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mass Density
Density (volumetric mass density or specific mass) is the ratio of a substance's mass to its volume. The symbol most often used for density is ''ρ'' (the lower case Greek language, Greek letter rho), although the Latin letter ''D'' (or ''d'') can also be used: \rho = \frac, where ''ρ'' is the density, ''m'' is the mass, and ''V'' is the volume. In some cases (for instance, in the United States oil and gas industry), density is loosely defined as its weight per unit volume, although this is scientifically inaccurate this quantity is more specifically called specific weight. For a pure substance, the density is equal to its mass concentration (chemistry), mass concentration. Different materials usually have different densities, and density may be relevant to buoyancy, purity and packaging. Osmium is the densest known element at standard conditions for temperature and pressure. To simplify comparisons of density across different systems of units, it is sometimes replaced by t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Density
The density of air or atmospheric density, denoted '' ρ'', is the mass per unit volume of Earth's atmosphere at a given point and time. Air density, like air pressure, decreases with increasing altitude. It also changes with variations in atmospheric pressure, temperature, and humidity. According to the ISO International Standard Atmosphere (ISA), the standard sea level density of air at 101.325 kPa (abs) and is . At the non-standard sea level temperature of , the density would decrease to . This is about that of water with a density of about . Air density is a property used in many branches of science, engineering, and industry, including aeronautics;Olson, Wayne M. (2000) AFFTC-TIH-99-01, Aircraft Performance FlightICAO, Manual of the ICAO Standard Atmosphere (extended to 80 kilometres (262 500 feet)), Doc 7488-CD, Third Edition, 1993, .Grigorie, T.L., Dinca, L., Corcau J-I. and Grigorie, O. (2010) Aircraft's Altitude Measurement Using Pressure Information:Barometric Altitud ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liquid Consonant
In linguistics, a liquid consonant or simply liquid is any of a class of consonants that consists of rhotics and voiced lateral approximants, which are also sometimes described as "R-like sounds" and "L-like sounds". The word ''liquid'' seems to be a calque of the Ancient Greek word (; ), initially used by grammarian Dionysius Thrax to describe Greek sonorants. Liquid consonants are more prone to be part of consonant clusters and of the syllable nucleus. Their third formants are generally non-predictable based on the first two formants. Another important feature is their complex articulation, which makes them a hard consonant class to study with precision and the last consonants to be produced by children during their phonological development. They are also more likely to undergo certain types of phonological changes such as assimilation, dissimilation and metathesis. Most languages have at least one liquid in their phonemic inventory. English has two, and . His ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rough Breathing
In the polytonic orthography of Ancient Greek, the rough breathing ( or ; ) character is a diacritical mark used to indicate the presence of an sound before a vowel, diphthong, or after rho. It remained in the polytonic orthography even after the Hellenistic period, when the sound disappeared from the Greek language. In the monotonic orthography of Modern Greek phonology, in use since 1982, it is not used at all. The absence of an sound is marked by the smooth breathing. The character, or those with similar shape such as , have also been used for a similar sound by Thomas Wade (and others) in the Wade–Giles system of romanization for Mandarin Chinese. Herbert Giles and others have used a left (opening) curved single quotation mark for the same purpose; the apostrophe, backtick, and visually similar characters are often seen as well. History The rough breathing comes from the left-hand half of the letter H. In some archaic Greek alphabets, the letter was used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greek Alphabet
The Greek alphabet has been used to write the Greek language since the late 9th or early 8th century BC. It was derived from the earlier Phoenician alphabet, and is the earliest known alphabetic script to systematically write vowels as well as consonants. In Archaic Greece, Archaic and early Classical Greece, Classical times, the Greek alphabet existed in Archaic Greek alphabets, many local variants, but, by the end of the 4th century BC, the Ionia, Ionic-based Euclidean alphabet, with 24 letters, ordered from alpha to omega, had become standard throughout the Greek-speaking world and is the version that is still used for Greek writing today. The letter case, uppercase and lowercase forms of the 24 letters are: : , , , , , , , , , , , , , , , , , , , , , , , The Greek alphabet is the ancestor of several scripts, such as the Latin script, Latin, Gothic alphabet, Gothic, Coptic script, Coptic, and Cyrillic scripts. Throughout antiquity, Greek had only a single uppercas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polytonic Orthography
Greek orthography has used a variety of diacritics starting in the Hellenistic period. The more complex polytonic orthography (), which includes five diacritics, notates Ancient Greek phonology. The simpler monotonic orthography (), introduced in 1982, corresponds to Modern Greek phonology, and requires only two diacritics. Polytonic orthography () is the standard system for Ancient Greek and Medieval Greek and includes: * acute accent () * circumflex accent () * grave accent (); these 3 accents indicate different kinds of pitch accent * rough breathing () indicates the presence of the sound before a letter * smooth breathing () indicates the absence of . Since in Modern Greek the pitch accent has been replaced by a stress (linguistics), dynamic accent (stress), and was lost, most polytonic diacritics have no phonetic significance, and merely reveal the underlying Ancient Greek etymology. Monotonic orthography () is the standard system for Modern Greek. It retains two dia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greek Numerals
Greek numerals, also known as Ionic, Ionian, Milesian, or Alexandrian numerals, is a numeral system, system of writing numbers using the letters of the Greek alphabet. In modern Greece, they are still used for ordinal number (linguistics), ordinal numbers and in contexts similar to those in which Roman numerals are still used in the Western world. For ordinary cardinal number (linguistics), cardinal numbers, however, modern Greece uses Arabic numerals. History The Minoans, Minoan and Mycenaean civilizations' Linear A and Linear B alphabets used a different system, called Aegean numerals, which included number-only symbols for powers of ten: = 1, = 10, = 100, = 1000, and = 10000. Attic numerals composed another system that came into use perhaps in the 7th century BC. They were acrophonic, derived (after the initial one) from the first letters of the names of the numbers represented. They ran = 1, = ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resh
Resh is the twentieth Letter (alphabet), letter of the Semitic abjads, including Phoenician alphabet, Phoenician ''rēš'' 𐤓, Hebrew alphabet, Hebrew ''rēš'' , Aramaic alphabet, Aramaic ''rēš'' 𐡓, Syriac alphabet, Syriac ''rēš'' ܪ, and Arabic script, Arabic ''rāʾ'' . It is related to the Ancient North Arabian 𐪇, Ancient South Arabian script, South Arabian , and Geʽez script, Ge'ez . Its sound value is one of a number of rhotic consonants: usually or , but also or in Hebrew and some North Mesopotamian Arabic dialects. In most Semitic alphabets, the letter resh (and its equivalents) is quite similar to the letter dalet (and its equivalents). In the Syriac alphabet, the letters became so similar that now they are only distinguished by a dot: resh has a dot above the letter, and the otherwise identical dalet has a dot below the letter. In the Arabic alphabet, has a longer tail than . In the Aramaic and Hebrew square alphabet, resh is a rounded single s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alveolar Approximant
The voiced alveolar and postalveolar approximants are types of consonantal sounds used in some spoken languages. The symbol in the International Phonetic Alphabet that represents the alveolar and postalveolar approximants is , a lowercase letter ''r'' rotated 180 degrees. The equivalent X-SAMPA symbol is r\. The most common sound represented by the letter ''r'' in English is the voiced postalveolar approximant, pronounced a little more back and transcribed more precisely in IPA as , but is often used for convenience in its place. For further ease of typesetting, English phonemic transcriptions might use the symbol even though this symbol represents the alveolar trill The voiced alveolar trill is a type of consonantal sound used in some spoken languages. The symbol in the International Phonetic Alphabet that represents dental consonant, dental, alveolar consonant, alveolar, and postalveolar consonant, postalve ... in phonetic transcription. The bunched or molar r sounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alveolar Tap
The voiced alveolar tap or flap is a type of consonantal sound, used in some spoken languages. The symbol in the International Phonetic Alphabet that represents a dental consonant, dental, alveolar consonant, alveolar, or postalveolar consonant, postalveolar tap and flap consonants, tap or flap is . The terms ''tap'' and ''flap'' are often used interchangeably. Peter Ladefoged proposed the distinction that a tap strikes its point of contact directly, as a very brief stop, and a flap strikes the point of contact tangentially: "Flaps are most typically made by retracting the tongue tip behind the alveolar ridge and moving it forward so that it strikes the ridge in passing." That distinction between the alveolar tap and flap can be written in the IPA with tap and flap , the 'retroflex' symbol being used for the one that starts with the tongue tip curled back behind the alveolar ridge. The distinction is noticeable in the speech of some American English speakers in distinguishing the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alveolar Trill
The voiced alveolar trill is a type of consonantal sound used in some spoken languages. The symbol in the International Phonetic Alphabet that represents dental consonant, dental, alveolar consonant, alveolar, and postalveolar consonant, postalveolar trill consonant, trills is , and the equivalent X-SAMPA symbol is r. It is commonly called the rolled R, rolling R, or trilled R. Quite often, is used in phonemic transcriptions (especially those found in dictionaries) of languages like English language, English and German language, German that have rhotic consonants that are not an alveolar trill. That is partly for ease of typesetting and partly because is the letter used in the orthographies of such languages. In many Indo-European languages, a trill may often be reduced to a single vibration in unstressed positions. In Italian, a simple trill typically displays only one or two vibrations, while a geminate trill will have three or more. Languages where trills always have multiple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lambda (letter)
Lambda (; uppercase , lowercase ; , ''lám(b)da'') is the eleventh letter of the Greek alphabet, representing the voiced alveolar lateral approximant . In the system of Greek numerals, lambda has a value of 30. Lambda is derived from the Phoenician Lamed. Lambda gave rise to the Latin L and the Cyrillic El (Л). The ancient grammarians and dramatists give evidence to the pronunciation as () in Classical Greek times. In Modern Greek, the name of the letter, Λάμδα, is pronounced . In early Greek alphabets, the shape and orientation of lambda varied. Most variants consisted of two straight strokes, one longer than the other, connected at their ends. The angle might be in the upper-left, lower-left ("Western" alphabets) or top ("Eastern" alphabets). Other variants had a vertical line with a horizontal or sloped stroke running to the right. With the general adoption of the Ionic alphabet, Greek settled on an angle at the top; the Romans put the angle at the lower-left. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
