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A synchronous electric motor is an AC electric motor in which, at steady state , the rotation of the shaft is synchronized with the frequency of the supply current ; the rotation period is exactly equal to an integer number of AC cycles. Synchronous motors use electromagnets as the stator of the motor which create a magnetic field that rotates in time with the oscillations of the current. The rotor with permanent magnets or electromagnets turns in step with the stator field at the same rate and as a result, provides the second synchronized rotating magnet field. Doubly fed synchronous motors use independently-excited multiphase AC electromagnets for both rotor and stator.

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75-408: " Death Dance " is the second single from American rock band Sevendust 's eleventh studio album, Kill the Flaw . The single was released to digital music outlets on March 22, 2016. It peaked at number twenty-nine on the Billboard Mainstream Rock chart. This metal song -related article is a stub . You can help Misplaced Pages by expanding it . This 2010s rock song -related article

150-408: A shaded-pole type. Costs are an important parameter for starters. Rotor excitation is a possible way to resolve the issue. In addition, starting methods for large synchronous machines include repetitive polarity inversion of the rotor poles during startup. By varying the excitation of a synchronous motor, it can be made to operate at lagging, leading and unity power factor . Excitation at which

225-532: A "single album" would otherwise be called a "single" or "extended play", depending on the length. As a distinct release type, the single album developed during the CD era in the 1990s. Single albums were marketed as a more affordable alternative to a full-length CD album. The Circle Album Chart tracks sales of all albums released as physical media (described as "offline" media), therefore, single albums compete alongside full-length studio albums (LPs) and mini-albums (EPs) on

300-470: A 46:1 gear ratio, resulting in a rotation speed of 78.3 rpm. With these factors applied to the 10-inch format, songwriters and performers increasingly tailored their output to fit the new medium. The three-minute single remained the standard into the 1960s, when the availability of microgroove recording and improved mastering techniques enabled recording artists to increase the duration of their recorded songs. The breakthrough came with Bob Dylan 's " Like

375-415: A Rolling Stone " in 1965: although Columbia Records tried to make the record more "radio-friendly" by cutting the performance into halves and separating them between the two sides of the disc , both Dylan and his fans demanded that the full six-minute take be placed on one side and that radio stations play the song in its entirety. The next milestone, which cemented pop radio's tolerance for longer songs,

450-403: A display such as a television set . The most common form of the vinyl single is the 45 or 7-inch . The names are derived from its play speed, 45 rpm, and the standard diameter, 7 inches (17.8 cm). The 45 rpm speed was chosen to allow a 5 + 1 ⁄ 2 minute playing time from the 7-inch disc. The 7-inch 45 rpm record was released March 31, 1949, by RCA Victor as

525-401: A drive system can operate at exactly the same speed. The power supply frequency determines motor operating speed. Hysteresis motors have a solid, smooth, cylindrical rotor, cast of a high coercivity magnetically "hard" cobalt steel. This material has a wide hysteresis loop (high coercivity ), meaning once it is magnetized in a given direction, it requires a high magnetic field to reverse

600-437: A foundation to sustain" and added that "When artists have one big record and go run with that, it doesn't work because they never had a foundation to begin with." The same article cited examples such as Cardi B , Camila Cabello and Jason Derulo releasing four or more singles prior to their album releases. Kanye West released singles weekly in 2010 with his GOOD Fridays series. He did this to support his upcoming release at

675-401: A large-hole record on a player with a quarter-inch spindle by inserting a single "puck" or by using a spindle adapter . Although 7 inches remained the standard size for vinyl singles, 12-inch singles were introduced for use by DJs in discos in the 1970s. The longer playing time of these singles allowed the inclusion of extended dance mixes of tracks. In addition, the larger surface area of

750-460: A major marketing mistake on the part of record companies, as it eliminated an inexpensive recording format for young fans to become accustomed to purchasing music. In its place was the predominance of the album, which alienated customers by the expense of purchasing a longer format for only one or two songs of interest. That in turn encouraged interest in file sharing software on the internet like Napster for single recordings, which began to undercut

825-410: A net lagging power factor, the presence of overexcited synchronous motors moves the system's net power factor closer to unity, improving efficiency. Such power-factor correction is usually a side effect of motors already present in the system to provide mechanical work, although motors can be run without mechanical load simply to provide power-factor correction. In large industrial plants such as factories

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900-422: A range of playback speeds (from 16 to 78  rpm ) and in several sizes (including 12 inches or 30 centimetres). By about 1910, however, the 10-inch (25 cm), 78-rpm shellac disc had become the most commonly used format. The inherent technical limitations of the gramophone disc defined the standard format for commercial recordings in the early 20th century. The relatively crude disc-cutting techniques of

975-483: A rate locked to the line frequency since they do not rely on induction to produce the rotor's magnetic field. Induction motors require slip : the rotor must rotate at a frequency slightly slower than the AC alternations in order to induce current in the rotor. Small synchronous motors are used in timing applications such as in synchronous clocks , timers in appliances, tape recorders and precision servomechanisms in which

1050-510: A remix. "Irony" was later included on their debut studio album The Wonder Years . A single album is distinct from a single even if it includes only one song. The single " Gotta Go " by Chungha was released on a single album titled XII , which was a one-track CD. Even though "Gotta Go" was the only song on XII , the two releases charted separately: XII reached No.   4 on the Gaon Album Chart, and "Gotta Go" reached No.   2 on

1125-448: A separate source or from a generator directly connected to the motor shaft. A permanent magnet synchronous motor and reluctance motor requires a control system for operating ( VFD or servo drive ). There is a large number of control methods for synchronous machines, selected depending on the construction of the electric motor and the scope. Control methods can be divided into: The PMSMs can also operate on open-loop control, which

1200-626: A smaller, more durable and higher- fidelity replacement for the 78 rpm shellac discs. The first 45 rpm records were monaural , with recordings on both sides of the disc. As stereo recordings became popular in the 1960s, almost all 45 rpm records were produced in stereo by the early 1970s. Columbia Records , which had released the 33 + 1 ⁄ 3  rpm 12-inch vinyl LP in June 1948, also released 33 + 1 ⁄ 3  rpm 7-inch vinyl singles in March 1949, but they were soon eclipsed by

1275-413: A solid steel cast rotor with projecting (salient) toothed poles. Typically there are fewer rotor than stator poles to minimize torque ripple and to prevent the poles from all aligning simultaneously—a position that cannot generate torque. The size of the air gap in the magnetic circuit and thus the reluctance is minimum when the poles align with the stator's (rotating) magnetic field, and increases with

1350-436: A squirrel cage in the rotor for starting—these are known as line-start or self-starting. These are typically used as higher-efficiency replacements for induction motors (owing to the lack of slip), but must ensure that synchronous speed is reached and that the system can withstand torque ripple during starting. PMSMs are typically controlled using direct torque control and field oriented control . Reluctance motors have

1425-447: A stationary armature and rotating field winding. This type of construction has an advantage over DC motor type where the armature used is of rotating type. Electric motors generate power due to the interaction of the magnetic fields of the stator and the rotor. In synchronous motors, the stator carries 3 phase currents and produces 3 phase rotating magnetic flux (and therefore a rotating magnetic field). The rotor eventually locks in with

1500-457: A synchronous machine shows armature current as a function of field current. With increasing field current armature current at first decreases, then reaches a minimum, then increases. The minimum point is also the point at which power factor is unity. This ability to selectively control power factor can be exploited for power factor correction of the power system to which the motor is connected. Since most power systems of any significant size have

1575-464: Is a stub . You can help Misplaced Pages by expanding it . Single (music) In music , a single is a type of release of a song recording of fewer tracks than an album or LP record , typically one or two tracks. A single can be released for sale to the public in a variety of physical or digital formats. Singles may be standalone tracks or connected to an artist's album, and in the latter case would often have at least one single release before

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1650-498: Is in operation, the speed of the motor is dependent only on the supply frequency. When the motor load is increased beyond the breakdown load, the motor falls out of synchronization and the rotor no longer follows the rotating magnetic field. Since the motor cannot produce torque if it falls out of synchronization, practical synchronous motors have a partial or complete squirrel-cage damper called an amortisseur winding to stabilize operation and facilitate starting. Because this winding

1725-431: Is not known, perhaps a copyright or other legal problem. The lightweight and inexpensive 45 rpm discs introduced by RCA were quickly popular and in the early 1950s all major US labels had begun manufacturing seven-inch singles. In the decades that followed, the seven-inch single was the format that many major artists made their recording debut on and some recordings were exclusively released as vinyl 45s only. According to

1800-417: Is operating at an AC supply frequency of 60 Hz. The number of pole-pairs is 6, so the synchronous speed is: The number of magnetic poles, p {\displaystyle p} , is equal to the number of coil groups per phase. To determine the number of coil groups per phase in a 3-phase motor, count the number of coils, divide by the number of phases, which is 3. The coils may span several slots in

1875-494: Is released specifically on physical media. A "single album" refers to a physical release (such as a CD, LP, or other media) that typically contains one to three unique tracks, while a "single" is only a song itself, typically a digital stream or download. Although the terms "single albums" and "singles" are similar and sometimes may overlap, they are generally considered two distinct release types in South Korea. In Western contexts,

1950-408: Is similar to that of a synchronous alternator . The stator frame contains wrapper plate (except for wound-rotor synchronous doubly fed electric machines ). Circumferential ribs and keybars are attached to the wrapper plate. To carry the weight of the machine, frame mounts and footings are required. The synchronous stator winding consists of a 3 phase winding. It is provided with a 3 phase supply, and

2025-420: Is smaller than that of an equivalent induction motor and can overheat on long operation, and because large slip-frequency voltages are induced in the rotor excitation winding, synchronous motor protection devices sense this condition and interrupt the power supply (out of step protection). Above a certain size, synchronous motors cannot self-start. This property is due to rotor inertia; it cannot instantly follow

2100-462: Is sometimes used for start-up thus enabling the position sensing operation. The synchronous speed of a synchronous motor is given: in RPM , by: and in rad·s , by: where: A single-phase , 4-pole (2-pole-pair) synchronous motor is operating at an AC supply frequency of 50 Hz. The number of pole-pairs is 2, so the synchronous speed is: A three-phase , 12-pole (6-pole-pair) synchronous motor

2175-524: Is unique and includes an additional term, the single album ( Korean :  싱글 음반 ; RR :  singgeul eumban ). In contemporary usage in English, the term "album" refers to an LP-length recording regardless of the medium. In contrast, under the country's copyright law, the Korean usage of "album" ( Korean :  음반 ; RR :  eumban ) denotes a musical recording of any length that

2250-536: The New York Times , the popularity of the seven-inch single reached a peak in 1974 when 200 million were sold. In the 1980s its popularity began to decline as jukeboxes became fewer, consumers tended to prefer to buy albums and formats such as cassettes and CDs was overtaking vinyl 45s. Despite its major decline, vinyl seven-inch singles has continued to released in the 2000s by indie labels such as Sub Pop and Third Man Records . In some regions (e.g. US),

2325-504: The Bandcamp storefront. Nowadays physically-released music is mainly bought in the form of full-length albums instead of singles. The most common physical formats of singles had been the 7" (45) vinyl records and the CD single , but singles have also been released on other formats such as 12" vinyl records , 10" shellac records, cassette single , and mini CD . The origins of the single are in

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2400-581: The Recording Industry Association of America (RIAA) introduced digital single certification due to significant sales of digital formats, with Gwen Stefani 's " Hollaback Girl " becoming RIAA's first platinum digital single. In 2013, RIAA incorporated on-demand streams into the digital single certification. Single sales in the United Kingdom reached a low in January 2005, as the popularity of

2475-421: The magnetic circuit of these machines needs to be able to concentrate the magnetic flux, typically leading to the use of spoke type rotors. Machines that use ferrite magnets have lower power density and torque density when compared with neodymium machines. PMSMs have been used as gearless elevator motors since 2000. Most PMSMs require a variable-frequency drive to start them. However, some incorporate

2550-469: The 12-inch discs allowed for wider grooves (larger amplitude) and greater separation between grooves, the latter of which results in less cross-talk. Consequently, they are less susceptible to wear and scratches. The 12-inch single is still considered a standard format for dance music , though its popularity has declined in recent years. Before the 7-inch single was introduced, 78 rpm 10-inch shellac records with around three minutes of music on them were

2625-516: The 1950s and 1960s. Singles in digital form became very popular in the 2000s. Distinctions for what makes a "single" have become more tenuous since: the biggest digital music distributor, the iTunes Store , only accepts as singles releases with three tracks or fewer that are less than ten minutes each (with longer releases being classified as " EPs " or "albums"). However, releases which do not fit these criteria have been promoted as singles by artists and labels elsewhere, such as on Spotify and

2700-578: The 2007 holiday season. The format included three songs by an artist, plus a ringtone accessible from the user's computer. Sony announced plans to release 50 singles in October and November, and Universal Music Group expected to release somewhere between 10 and 20 titles. In a reversal of this trend, a single has been released based on a ringtone itself: the Crazy Frog ringtone, which was a cult hit in Europe in 2004,

2775-567: The 45 player in March 1949. There was plenty of information leaked to the public about the new 45 rpm system through front-page articles in Billboard magazine on December 4, 1948, and again on January 8, 1949. RCA was trying to blunt the lead Columbia had established upon releasing their 33 + 1 ⁄ 3   LP system in June 1948. To compete with Columbia, RCA released albums as boxes of 45 rpm seven-inch singles that could be played continuously like an LP on their record changer. RCA

2850-622: The Circle Digital Chart. Even when a single album and single share the same name, they still chart separately, as was the case with the Wonder Girls single album and single " Why So Lonely ": the single album peaked at No. 3 on the Gaon Album Chart, while the single peaked at No. 1 on the Gaon Digital Chart. Synchronous motor Synchronous and induction motors are the most widely used AC motors. Synchronous motors rotate at

2925-675: The RCA Victor 45. The first regular production 45 rpm record pressed was "PeeWee the Piccolo": RCA Victor 47-0146 pressed December 7, 1948 at the Sherman Avenue plant in Indianapolis ; R.O. Price, plant manager. The claim made that 48-0001 by Eddy Arnold was the first 45 is evidently incorrect (even though 48-0000 has not turned up, 50-0000-Crudup, 51-0000-Meisel, and 52-0000 Goodman are out there) since all 45s were released simultaneously with

3000-551: The United States as albums, which on compact disc had virtually identical production and distribution costs but could be sold at a higher price, became most retailers' primary method of selling music. Singles continued to be produced in the UK and Australia and survived the transition from compact disc to digital download. The decline of the physical single in the US during this time has been cited as

3075-439: The album itself, called lead singles . The single was defined in the mid-20th century with the 45 (named after its speed in revolutions per minute ), a type of 7-inch sized vinyl record containing an A-side and a B-side , i.e. one song on each side. The single format was highly influential in pop music and the early days of rock and roll , and it was the format used for jukeboxes and preferred by younger populations in

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3150-437: The angle between them. This creates torque that pulls the rotor into alignment with the nearest pole of the stator field. At synchronous speed the rotor is thus "locked" to the rotating stator field. This cannot start the motor, so the rotor poles usually have squirrel-cage windings embedded in them, to provide torque below synchronous speed. The machine thus starts as an induction motor until it approaches synchronous speed, when

3225-474: The chart, even if they only contain one song. The Circle Digital Chart , which tracks downloads and streams of sole tracks, is regarded as the official "singles" chart. To give an example of the differences between full-length albums, single albums, and singles, the K-pop girl group Wonder Girls released the single album The Wonder Begins , which consists of the single "Irony" alongside two other unique tracks and

3300-549: The compact disc was overtaken by the then-unofficial medium of the music download. Recognizing this, on 17 April 2005, Official UK Singles Chart added the download format to the existing format of physical CD singles. Gnarls Barkley was the first act to reach No.1 on this chart through downloads alone in April 2006, for their debut single " Crazy ", which was released physically the following week. On 1 January 2007, digital downloads (including unbundled album tracks ) became eligible from

3375-430: The default hole size fitted the original RCA 1.5-inch (3.8 cm) hub which, due to a format war , was incompatible with the 0.25-inch (6.4 mm) spindle of a Columbia-system 33 1/3 RPM 12-inch LP player. In other regions (e.g. UK, Australia), the default was a small hole compatible with a multi-speed 0.25-inch spindle player, but with a "knock out" that could be removed for usage on a larger hub player. One could play

3450-528: The interaction between synchronous motors and other, lagging, loads may be an explicit consideration in the plant's electrical design. where, here, When load is applied, torque angle δ {\displaystyle \delta } increases. When δ {\displaystyle \delta } = 90° the torque will be maximum. If load is applied further then the motor will lose its synchronism, since motor torque will be less than load torque. The maximum load torque that can be applied to

3525-457: The introduction of Apple's iTunes Store originally known as iTunes in January 2001, along with the emergence of portable music devices like the iPod . In September 1997, with the release of Duran Duran 's " Electric Barbarella " for paid downloads, Capitol Records became the first major label to sell a digital single from a well-known artist. Previously, Geffen Records also released Aerosmith 's " Head First " digitally for free. In 2004,

3600-546: The late 19th century, when music was distributed on phonograph cylinders that held two to four minutes' worth of audio. They were superseded by disc phonograph records , which initially also had a short duration of playing time per side. In the first two to three decades of the 20th century, almost all commercial music releases were, in effect, singles (the exceptions were usually for classical music pieces, where multiple physical storage media items were bundled together and sold as an album). Phonograph records were manufactured with

3675-492: The list. To be eligible for inclusion in charts, the single must meet the requirement set by the charting company that governs the playing time of the single. In popular music , the commercial and artistic importance of the single (as compared to the EP or album) has varied over time, technological development, and according to the audience of particular artists and genres. Singles have generally been more important to artists who sell to

3750-426: The magnetization. The rotating stator field causes each small volume of the rotor to experience a reversing magnetic field. Because of hysteresis the phase of the magnetization lags behind the phase of the applied field. Thus the axis of the magnetic field induced in the rotor lags behind the axis of the stator field by a constant angle δ, producing torque as the rotor tries to "catch up" with the stator field. As long as

3825-462: The motor must operate at a precise speed; accuracy depends on the power line frequency , which is carefully controlled in large interconnected grid systems. Synchronous motors are available in self-excited, fractional to industrial sizes. In the fractional power range, most synchronous motors are used to provide precise constant speed. These machines are commonly used in analog electric clocks, timers and related devices. In typical industrial sizes,

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3900-426: The music recording market. Dance music , however, has followed a different commercial pattern and the single, especially the 12-inch vinyl single, remains a major method by which dance music is distributed. Another development of the 2000s was the popularity of mobile phone ringtones based on pop singles. In September 2007, Sony BMG announced that it would introduce a new type of CD single, called "ringles", for

3975-430: The point of release, without the need for an accompanying physical. Sales gradually improved in the following years, reaching a record high in 2008 that still proceeded to be overtaken in 2009, 2010 and 2011. In the late 2010s, artists began a trend of releasing multiple singles before eventually releasing a studio album. An unnamed A&R representative confirmed to Rolling Stone in 2018 that "an artist has to build

4050-453: The power factor is unity is termed normal excitation voltage . The magnitude of current at this excitation is minimum. Excitation voltage more than normal excitation is called over excitation voltage, excitation voltage less than normal excitation is called under excitation. When the motor is over excited, the back emf will be greater than the motor terminal voltage. This causes a demagnetizing effect due to armature reaction. The V curve of

4125-459: The power line frequency to run the gear mechanism at the correct speed. Such small synchronous motors are able to start without assistance if the moment of inertia of the rotor and its mechanical load are sufficiently small. The motor accelerates from slip speed to synchronous speed during an accelerating half cycle of the reluctance torque. Single-phase synchronous motors such as in electric wall clocks can freely rotate in either direction, unlike

4200-413: The reluctance type, hysteresis motors are used where precise constant speed is required. Usually made in larger sizes (larger than about 1 horsepower or 1 kilowatt) these motors require direct current (DC) to excite (magnetize) the rotor. This is most straightforwardly supplied through slip rings . A brushless AC induction and rectifier arrangement can also be used. The power may be supplied from

4275-418: The resultant air-gap flux by the forward motion of the prime mover ". Motor action occurs if the field poles are "dragged behind the resultant air-gap flux by the retarding torque of a shaft load ". The two major types of synchronous motors are distinguished by how the rotor is magnetized: non-excited and direct-current excited. In non-excited motors, the rotor is made of steel. It rotates in step with

4350-405: The rotating magnetic field and rotates along with it. Once the rotor field locks in with the rotating magnetic field, the motor is said to be synched. A single-phase (or two-phase derived from single phase) stator is possible, but in this case the direction of rotation is not defined and the machine may start in either direction unless prevented from doing so by startup arrangements. Once the motor

4425-538: The rotating stator field. A major advantage of the hysteresis motor is that since the lag angle δ is independent of speed, it develops constant torque from startup to synchronous speed. Therefore, it is self-starting and doesn't need an induction winding to start it, although many designs embed a squirrel-cage conductive winding structure in the rotor to provide extra torque at start-up. Hysteresis motors are manufactured in sub-fractional horsepower ratings, primarily as servomotors and timing motors. More expensive than

4500-406: The rotation of the stator's magnetic field. Since a synchronous motor produces no inherent average torque at standstill, it cannot accelerate to synchronous speed without a supplemental mechanism. Large motors operating on commercial power include a squirrel-cage induction winding that provides sufficient torque for acceleration and also serves to damp motor speed oscillations. Once the rotor nears

4575-422: The rotor "pulls in" and locks to the stator field. Reluctance motor designs have ratings that range from fractional horsepower (a few watts) to about 22 kW . Small reluctance motors have low torque , and are generally used for instrumentation applications. Moderate torque, multi-horsepower motors use squirrel cage construction with toothed rotors. When used with an adjustable frequency power supply, all motors in

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4650-420: The rotor is below synchronous speed, each particle of the rotor experiences a reversing magnetic field at the "slip" frequency that drives it around its hysteresis loop, causing the rotor field to lag and create torque. The rotor has a 2-pole low reluctance bar structure. As the rotor approaches synchronous speed and slip goes to zero, this magnetizes and aligns with the stator field, causing the rotor to "lock" to

4725-422: The rotor is provided with a DC supply. DC excited motors require brushes and slip rings to connect to the excitation supply. The field winding can be excited by a brushless exciter. Cylindrical, round rotors, (also known as non-salient pole rotor) are used for up to six poles. In some machines or when a large number of poles are needed, a salient pole rotor is used. Most synchronous motor construction uses

4800-491: The rotor to create a constant magnetic field. The stator carries windings connected to an AC electricity supply to produce a rotating magnetic field (as in an asynchronous motor ). At synchronous speed the rotor poles lock to the rotating magnetic field. PMSMs are similar to brushless DC motors . Neodymium magnets are the most common, although rapid fluctuation of neodymium magnet prices triggered research in ferrite magnets . Due to inherent characteristics of ferrite magnets ,

4875-462: The standard format. Later, 10-inch vinyl singles have commonly been released as limited edition collectors items, which sometimes includes rare tracks or special artwork. With the rise of digital downloading and audio streaming, individual tracks within an album became accessible separately. Despite this shift, the notion of a "single" from an album remains, pinpointing the more promoted or favored songs. The surge in music downloads escalated following

4950-479: The stator core, making it tedious to count them. For a 3-phase motor, if you count a total of 12 coil groups, it has 4 magnetic poles. For a 12-pole 3-phase machine, there will be 36 coils. The number of magnetic poles in the rotor is equal to the number of magnetic poles in the stator. The principal components of electric motors are the stator and the rotor. Synchronous motor and induction motor stators are similar in construction. The construction of synchronous motor

5025-429: The stator's rotating magnetic field, so it has an almost-constant magnetic field through it. The external stator field magnetizes the rotor, inducing the magnetic poles needed to turn it. The rotor is made of a high- retentivity steel such as cobalt steel. These are manufactured in permanent magnet , reluctance and hysteresis designs: A permanent-magnet synchronous motor (PMSM) uses permanent magnets embedded in

5100-425: The synchronous motor provides an efficient means of converting AC energy to work ( electrical efficiency above 95% is normal for larger sizes) and it can operate at leading or unity power factor and thereby provide power-factor correction. Synchronous motors fall under the category of synchronous machines that also includes synchronous generators. Generator action occurs if the field poles are "driven ahead of

5175-451: The synchronous speed, the field winding becomes excited and the motor pulls into synchronization. Very large motor systems may include a "pony" motor that accelerates the unloaded synchronous machine before load is applied. Electronically controlled motors can be accelerated from zero speed by changing the frequency of the stator current. Small synchronous motors are commonly used in line-powered electric mechanical clocks or timers that use

5250-411: The time and the thickness of the needles used on record players limited the number of grooves per inch that could be inscribed on the disc surface and a high rotation speed was necessary to achieve acceptable recording and playback fidelity. 78 rpm was chosen as the standard because of the introduction of the electrically powered synchronous turntable motor in 1925, which ran at 3,600 rpm with

5325-514: The time, My Beautiful Dark Twisted Fantasy , and ended up releasing 15 tracks in the program. CD singles and 7-inch records are now obscure and uncommon for new releases: as of the 2020s singles are predominantly digital, and physical releases are mainly full-length albums instead, on CD and 12-inch LPs. The sales of singles are recorded in record charts in most countries in a Top 40 format. The charts are often published in magazines and numerous television shows and radio programs count down

5400-445: The youngest purchasers of music (younger teenagers and pre-teens ), who tend to have more limited financial resources. Starting in the mid-1960s, albums became a greater focus and became more important as artists created albums of uniformly high-quality and coherent themes, a trend that reached its apex in the development of the concept album . Over the 1990s and the early 2000s, the single generally received less and less attention in

5475-466: Was also releasing 7-inch singles pressed in different colors for different genres, making it easy for customers to find their preferred music. The novelty of multicolored singles wore off soon: by 1952, all RCA singles were pressed in black vinyl. The lowest recording numbers found (so far) for each genre of RCA 45s are: 47-0146 yellow, 47-2715 black, 48-0001 green, 49-0100 deep red, 50-0000 cerise, 51-0000 light blue. 52-0000 deep blue. What became of 48-0000

5550-459: Was released as a mashup with " Axel F " in June 2005 amid a massive publicity campaign and subsequently hit No. 1 on the UK chart. The term single is sometimes regarded as a misnomer since one record usually contains two songs: the A-side and B-side . In 1982, CBS marketed one-sided singles at a lower price than two-sided singles. In South Korean music , the terminology for "albums" and "singles"

5625-762: Was the Beatles Hey Jude ; released August 1968 it clocked in at over seven minutes, pushing the limits of the 45 rpm single. Singles have been issued in various formats, including 7-inch (18 cm), 10-inch and 12-inch discs, usually playing at 45 rpm; 10-inch shellac discs, playing at 78 rpm; maxi singles ; 7-inch plastic flexi discs ; cassettes ; 8 or 12 cm (3.1 or 4.7 in) CD singles, and less commonly on Digital Compact Cassette and many non-standard sizes of vinyl disc (5 in or 13 cm, 8 in or 20 cm, etc.). Singles were also released on DVD and Laserdisc video formats, which would additionally contain music videos to be watched on

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