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| | If you think of oneself because being fat plus ugly then this is the appropriate place for you. In this article there is a step-by-step representation of Ways to Lose fat. For many fat loss can prove to be a quite difficult problem to deal with due to the truth which they just do not have the idea of how to burn the calories and what to avoid plus what to eat which may provide the nourishment without piling up the calories.<br><br>Leafy greens are high in fiber, low in calories, packed full of compounds, plus around half their digestible calories come from protein. Eating at least 10 servings of greens a day can replace a great deal of the high calorie foods inside the diet, nevertheless leave you simply because full. If you should lose weight fast, eat a greens. If you have to lose fat faster, eat MORE greens. I highly recommend drinking a green smoothie for breakfast every morning.<br><br>In regards to the quickest method to lose weight, sleep is actually an often overlooked component. People merely talk about eating plus working out to lose fat. Not everybody ever says sleeping is critical for fat reduction. Yet somehow, this absolutely is regarded as the many important components inside the weight-loss equation.<br><br>With all programs you need to know that you have to be self disciplined plus follow it properly. Here are some easy strategies for fat loss in a rush.<br><br>And when I am seized with all the temptation of the wicked doughnut, I could resist-at least for a moment [http://safedietplansforwomen.com/how-to-lose-weight-fast how to lose weight fast for women]. And then another moment, until I've put enough time between the impulse plus the action, and the craving has subsided.<br><br>Cardio is an aerobic exercise which you do for hours at slow - moderate pace with an intensity level where you are able to nevertheless talk. It does burn fat yet only throughout the exercise bout. When we stop, the fat-burning impact stops.<br><br>Losing weight is pretty difficult, however, with this we should be able to get to a fat goal. If you have any question, comments or concerns please feel free to comment. For an expert opinion please contact the regional physician or dietician. |
| [[Image:Angle of attack.svg|thumb|right|300px|In this diagram, the black lines represent the flow of a fluid around a two-dimensional [[airfoil]] shape. The angle α is the angle of attack.]]
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| In [[fluid dynamics]], '''angle of attack''' ('''AOA''', or '''<math>\alpha</math>''' ([[Greek alphabet|Greek letter]] [[alpha (letter)|alpha]])) is the [[angle]] between a [[Airfoil#Airfoil terminology|reference line]] on a body (often the [[chord (aircraft)|chord line]] of an [[airfoil]]) and the [[vector (geometry)|vector]] representing the relative motion between the body and the fluid through which it is moving.<ref name="nasa">{{cite web|url=http://www.grc.nasa.gov/WWW/k-12/airplane/incline.html|title=NASA aeronautics guided tour}}</ref> Angle of attack is the angle between the body's reference line and the oncoming flow. This article focuses on the most common application, the angle of attack of a wing or airfoil moving through air.
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| In [[aerodynamics]], angle of attack specifies the angle between the chord line of the wing of a [[fixed-wing aircraft]] and the vector representing the relative motion between the aircraft and the atmosphere. Since a wing can have twist, a chord line of the whole wing may not be definable, so an alternate reference line is simply defined. Often, the chord line of the [[Wing root|root of the wing]] is chosen as the reference line. Another choice is to use a horizontal line on the fuselage as the reference line (and also as the longitudinal axis).<ref>{{cite journal |title=Summary of Methods of Measuring Angle of Attack on Aircraft |url=http://naca.central.cranfield.ac.uk/reports/1958/naca-tn-4351.pdf |issue=NACA-TN-4351 |journal=NACA Technical Note |first=William |last=Gracey |year=1958 |pages=1–30 |publisher=NASA Technical Reports}}</ref> Some authors<ref name="SHIF">John S. Denker, ''See How It Flies''. http://www.av8n.com/how/htm/aoa.html#sec-def-aoa</ref><ref name="SnH">Wolfgang Langewiesche, ''Stick and Rudder: An Explanation of the Art of Flying'', McGraw-Hill Professional, first edition (September 1, 1990), ISBN 0-07-036240-8</ref> do not use an arbitrary chord line, but use the [[zero lift axis]] instead — zero angle of attack corresponds to zero [[Lift coefficient|coefficient of lift]].
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| Some British authors have used the term [[Angle_of_incidence#Angle of incidence of fixed-wing aircraft|''angle of incidence'']] instead of ''angle of attack''. However, this can lead to confusion with the term ''riggers' angle of incidence'' meaning the angle between the chord of an aerofoil and some fixed datum in the aeroplane.<ref>Kermode, A.C. (1972), ''Mechanics of Flight'', Chapter 3 (8th edition), Pitman Publishing Limited, London ISBN 0-273-31623-0</ref>
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| ==Relation between angle of attack and lift==
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| [[Image:Lift curve.svg|thumb|300px|right|A typical [[lift coefficient]] curve.]]
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| The [[lift coefficient]] of a [[fixed-wing aircraft]] varies with angle of attack. Increasing angle of attack is associated with increasing lift coefficient up to the maximum lift coefficient, after which lift coefficient decreases.<ref name="nasa-lc">{{cite web|url=http://www.grc.nasa.gov/WWW/k-12/airplane/liftco.html|title=NASA Lift Coefficient}}</ref>
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| As the angle of attack of a fixed-wing aircraft increases, [[Flow separation|separation]] of the airflow from the upper surface of the wing becomes more pronounced, leading to a reduction in the rate of increase of the lift coefficient. The figure shows a typical curve for a [[Camber (aerodynamics)|cambered]] straight wing. A symmetrical wing has zero lift at 0 degrees angle of attack. The lift curve is also influenced by wing [[planform]]. A [[swept wing]] has a lower, flatter curve with a higher critical angle.
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| ==Critical angle of attack==
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| The '''critical angle of attack''' is the angle of attack which produces maximum lift coefficient. This is also called the "stall angle of attack". Below the critical angle of attack, as the angle of attack increases, the coefficient of lift (Cl) increases. At the same time, above the critical angle of attack, as angle of attack increases, the air begins to flow less smoothly over the upper surface of the [[airfoil]] and begins to separate from the upper surface. On most airfoil shapes, as the angle of attack increases, the upper surface separation point of the flow moves from the trailing edge towards the leading edge. At the critical angle of attack, upper surface flow is more separated and the airfoil or wing is producing its maximum coefficient of lift. As angle of attack increases further, the upper surface flow becomes more and more fully separated and the airfoil/wing produces less coefficient of lift.<ref name="nasa-lc" />
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| Above this critical angle of attack, the aircraft is said to be in a [[Stall (flight)|stall]]. A fixed-wing aircraft by definition is stalled at or above the critical angle of attack rather than at or below a particular [[airspeed]]. The airspeed at which the aircraft stalls varies with the weight of the aircraft, the [[load factor (aeronautics)|load factor]], the center of gravity of the aircraft and other factors. However the aircraft always stalls at the same critical angle of attack. The critical or stalling angle of attack is typically around 15° for many airfoils.
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| Some aircraft are equipped with a built-in flight computer that automatically prevents the aircraft from increasing the angle of attack any further when a maximum angle of attack is reached, irrespective of pilot input. This is called the 'angle of attack limiter' or 'alpha limiter'. Modern airliners that have fly-by-wire technology avoid the critical angle of attack by means of software in the computer systems that govern the flight control surfaces.
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| In takeoff and landing operations from short runways, such as Naval Aircraft Carrier operations and [[STOL]] back country flying, aircraft may be equipped with angle of attack or [[Airspeed indicator#Variations|Lift Reserve Indicators]]. These indicators measure the angle of attack (AOA) or the Potential of Wing Lift (POWL, or Lift Reserve) directly and help the pilot fly close to the stalling point with greater precision. [[STOL]] operations require the aircraft to be able to operate close to the critical angle of attack during landings and at the best angle of climb during takeoffs. Angle of attack indicators are used by pilots for maximum performance during these maneuvers since airspeed information is only indirectly related to stall behaviour.
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| ==Very high alpha==
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| {{further|High Alpha Research Vehicle}}
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| Some military aircraft are able to achieve very high angles of attack, but at the cost of massive [[induced drag]]. This provides the aircraft with great agility. A famous military example is sometimes thought to be [[Pugachev's Cobra]]. This ''high pitch'' (the angle between the chord and level flight) maneuver is technically, by definition, not quite a true angle of attack,<ref>http://www.advanced-flight-systems.com/Support/AOAsupport/AOA%20slides.ppt</ref> but is more accurately, [[Supermaneuverability|supermaneuvering]]<ref>[http://books.google.com/books?id=Ti3lNwAACAAJ&dq=inauthor:%22Timothy+John+Cowan%22&source=bl&ots=3a8KzWbZih&sig=yPdiiPriU8W7QSv3DCDb0guA3HI&hl=en&sa=X&ei=0PCCUIW4MaS-2gWPlIHICw&ved=0CDAQ6AEwAA Timothy Cowan]</ref><ref>[http://www.dtic.mil/dtic/tr/fulltext/u2/a224126.pdf DTIC]</ref> by means of [[thrust vectoring]] the whole airframe -- as the airflow, motion vector and wing chord or primary lift devices, are not in a classical angle-of-attack relationship.
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| Additional aerodynamic surfaces known as "high-lift devices" including [[Leading edge extension#Leading edge root extensions|leading edge wing root extensions]] allow [[fighter aircraft]] much greater flyable 'true' alpha, up to over 45°, compared to about 20° for aircraft without these devices. However, military aircraft usually do not obtain such high alpha in combat, as it robs the aircraft of speed very quickly. Not only do such maneuvers slow the aircraft down, but they cause significant structural stress at high speed. Modern flight control systems tend to limit a fighter's angle of attack to well below its maximum aerodynamic limit.{{cn|date=November 2012}}
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| ==Sailing==
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| In [[sailing]], the physical principles involved are the same as for aircraft.<ref name="MIT - How Sails Work">{{cite web|last=Evans|first=Robin C.|title=HOW A SAIL BOAT SAILS INTO THE WIND|url=http://web.mit.edu/2.972/www/reports/sail_boat/sail_boat.html|work=Reports on How Things Work|publisher=Massachusetts Institute of Technology|accessdate=14 January 2012}}</ref> A sail's '''angle of attack''' is the angle between the sail's chord line and the direction of the wind.
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| A boat's '''angle of attack''' is the angle between the boat's course and the wind direction. See [[points of sail]].
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| ==See also==
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| *[[Advance ratio]]
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| *[[Airfoil]]
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| *[[Angle of incidence]]
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| *[[Angle of sideslip]]
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| *[[Bernoulli's principle]]
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| *[[Camber (aerodynamics)|Camber]]
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| *[[Drag equation]]
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| *[[Lift coefficient]]
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| *[[Lift (force)]]
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| *[[Flight dynamics (aircraft)|Pitch]]
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| *[[Stall (flight)]]
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| *[[Zero lift axis]]
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| ==References==
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| {{Reflist}}
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| * Lawford, J.A. and Nippress, K.R.; [http://spaceagecontrol.com/AD-CalibrationOfAirDataSystemsAndFlowDirectionSensors.pdf Calibration of Air-data Systems and Flow Direction Sensors] (NATO) Advisory Group for Aerospace Research and Development, AGARDograph No. 300 Vol. 1 (AGARD AG-300 Vol. 1); "Calibration of Air-data Systems and Flow Direction Sensors"; Aeroplane and Armament Experimental Establishment, Boscombe Down, Salisbury, Wilts SP4 OJF, United Kingdom
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| * USAF & NATO Report RTO-TR-015 AC/323/(HFM-015)/TP-1 (2001).
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| {{DEFAULTSORT:Angle Of Attack}}
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| [[Category:Aerodynamics]]
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| [[Category:Aircraft wing design]]
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| [[Category:Kites]]
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If you think of oneself because being fat plus ugly then this is the appropriate place for you. In this article there is a step-by-step representation of Ways to Lose fat. For many fat loss can prove to be a quite difficult problem to deal with due to the truth which they just do not have the idea of how to burn the calories and what to avoid plus what to eat which may provide the nourishment without piling up the calories.
Leafy greens are high in fiber, low in calories, packed full of compounds, plus around half their digestible calories come from protein. Eating at least 10 servings of greens a day can replace a great deal of the high calorie foods inside the diet, nevertheless leave you simply because full. If you should lose weight fast, eat a greens. If you have to lose fat faster, eat MORE greens. I highly recommend drinking a green smoothie for breakfast every morning.
In regards to the quickest method to lose weight, sleep is actually an often overlooked component. People merely talk about eating plus working out to lose fat. Not everybody ever says sleeping is critical for fat reduction. Yet somehow, this absolutely is regarded as the many important components inside the weight-loss equation.
With all programs you need to know that you have to be self disciplined plus follow it properly. Here are some easy strategies for fat loss in a rush.
And when I am seized with all the temptation of the wicked doughnut, I could resist-at least for a moment how to lose weight fast for women. And then another moment, until I've put enough time between the impulse plus the action, and the craving has subsided.
Cardio is an aerobic exercise which you do for hours at slow - moderate pace with an intensity level where you are able to nevertheless talk. It does burn fat yet only throughout the exercise bout. When we stop, the fat-burning impact stops.
Losing weight is pretty difficult, however, with this we should be able to get to a fat goal. If you have any question, comments or concerns please feel free to comment. For an expert opinion please contact the regional physician or dietician.