Ogive
Overview
 
An ogive is the roundly tapered end of a two-dimensional or three-dimensional object.
In ballistics
Ballistics
Ballistics is the science of mechanics that deals with the flight, behavior, and effects of projectiles, especially bullets, gravity bombs, rockets, or the like; the science or art of designing and accelerating projectiles so as to achieve a desired performance.A ballistic body is a body which is...

 or aerodynamics
Aerodynamics
Aerodynamics is a branch of dynamics concerned with studying the motion of air, particularly when it interacts with a moving object. Aerodynamics is a subfield of fluid dynamics and gas dynamics, with much theory shared between them. Aerodynamics is often used synonymously with gas dynamics, with...

, an ogive is a pointed, curved surface mainly used to form the approximately streamlined nose of a bullet or other projectile.

The traditional or secant
Secant line
A secant line of a curve is a line that intersects two points on the curve. The word secant comes from the Latin secare, to cut.It can be used to approximate the tangent to a curve, at some point P...

 ogive is a surface of revolution
Surface of revolution
A surface of revolution is a surface in Euclidean space created by rotating a curve around a straight line in its plane ....

 of the same curve that forms a Gothic arch
Gothic architecture
Gothic architecture is a style of architecture that flourished during the high and late medieval period. It evolved from Romanesque architecture and was succeeded by Renaissance architecture....

; that is, a circular arc
Arc (geometry)
In geometry, an arc is a closed segment of a differentiable curve in the two-dimensional plane; for example, a circular arc is a segment of the circumference of a circle...

, of greater radius
Radius
In classical geometry, a radius of a circle or sphere is any line segment from its center to its perimeter. By extension, the radius of a circle or sphere is the length of any such segment, which is half the diameter. If the object does not have an obvious center, the term may refer to its...

 than the diameter of the cylindrical
Cylinder (geometry)
A cylinder is one of the most basic curvilinear geometric shapes, the surface formed by the points at a fixed distance from a given line segment, the axis of the cylinder. The solid enclosed by this surface and by two planes perpendicular to the axis is also called a cylinder...

 section ("shank"), is drawn from the edge of the shank until it intercepts the axis.

If this arc is drawn so that it meets the shank at zero angle (that is, the distance of the centre of the arc from the axis, plus the radius of the shank, equals the radius of the arc), then it is called a tangent
Tangent
In geometry, the tangent line to a plane curve at a given point is the straight line that "just touches" the curve at that point. More precisely, a straight line is said to be a tangent of a curve at a point on the curve if the line passes through the point on the curve and has slope where f...

ial or spitzer
Spitzer (bullet)
A spitzer, also commonly referred to as a spire point bullet, is an aerodynamic bullet design used in most intermediate and high-powered rifle cartridges...

 ogive.
Encyclopedia
An ogive is the roundly tapered end of a two-dimensional or three-dimensional object.

Applied physical science and engineering

In ballistics
Ballistics
Ballistics is the science of mechanics that deals with the flight, behavior, and effects of projectiles, especially bullets, gravity bombs, rockets, or the like; the science or art of designing and accelerating projectiles so as to achieve a desired performance.A ballistic body is a body which is...

 or aerodynamics
Aerodynamics
Aerodynamics is a branch of dynamics concerned with studying the motion of air, particularly when it interacts with a moving object. Aerodynamics is a subfield of fluid dynamics and gas dynamics, with much theory shared between them. Aerodynamics is often used synonymously with gas dynamics, with...

, an ogive is a pointed, curved surface mainly used to form the approximately streamlined nose of a bullet or other projectile.

The traditional or secant
Secant line
A secant line of a curve is a line that intersects two points on the curve. The word secant comes from the Latin secare, to cut.It can be used to approximate the tangent to a curve, at some point P...

 ogive is a surface of revolution
Surface of revolution
A surface of revolution is a surface in Euclidean space created by rotating a curve around a straight line in its plane ....

 of the same curve that forms a Gothic arch
Gothic architecture
Gothic architecture is a style of architecture that flourished during the high and late medieval period. It evolved from Romanesque architecture and was succeeded by Renaissance architecture....

; that is, a circular arc
Arc (geometry)
In geometry, an arc is a closed segment of a differentiable curve in the two-dimensional plane; for example, a circular arc is a segment of the circumference of a circle...

, of greater radius
Radius
In classical geometry, a radius of a circle or sphere is any line segment from its center to its perimeter. By extension, the radius of a circle or sphere is the length of any such segment, which is half the diameter. If the object does not have an obvious center, the term may refer to its...

 than the diameter of the cylindrical
Cylinder (geometry)
A cylinder is one of the most basic curvilinear geometric shapes, the surface formed by the points at a fixed distance from a given line segment, the axis of the cylinder. The solid enclosed by this surface and by two planes perpendicular to the axis is also called a cylinder...

 section ("shank"), is drawn from the edge of the shank until it intercepts the axis.

If this arc is drawn so that it meets the shank at zero angle (that is, the distance of the centre of the arc from the axis, plus the radius of the shank, equals the radius of the arc), then it is called a tangent
Tangent
In geometry, the tangent line to a plane curve at a given point is the straight line that "just touches" the curve at that point. More precisely, a straight line is said to be a tangent of a curve at a point on the curve if the line passes through the point on the curve and has slope where f...

ial or spitzer
Spitzer (bullet)
A spitzer, also commonly referred to as a spire point bullet, is an aerodynamic bullet design used in most intermediate and high-powered rifle cartridges...

 ogive. This is a very common ogive for high velocity (supersonic
Supersonic
Supersonic speed is a rate of travel of an object that exceeds the speed of sound . For objects traveling in dry air of a temperature of 20 °C this speed is approximately 343 m/s, 1,125 ft/s, 768 mph or 1,235 km/h. Speeds greater than five times the speed of sound are often...

) rifle
Rifle
A rifle is a firearm designed to be fired from the shoulder, with a barrel that has a helical groove or pattern of grooves cut into the barrel walls. The raised areas of the rifling are called "lands," which make contact with the projectile , imparting spin around an axis corresponding to the...

 bullets.
The sharpness of this ogive is expressed by the ratio of its radius to the diameter of the cylinder; a value of one half being a hemispherical
Sphere
A sphere is a perfectly round geometrical object in three-dimensional space, such as the shape of a round ball. Like a circle in two dimensions, a perfect sphere is completely symmetrical around its center, with all points on the surface lying the same distance r from the center point...

 dome, and larger values being progressively more pointed. Values of 4 to 10 are commonly used in rifles, with 6 being the most common.

Another common ogive for bullets is the elliptical
Ellipse
In geometry, an ellipse is a plane curve that results from the intersection of a cone by a plane in a way that produces a closed curve. Circles are special cases of ellipses, obtained when the cutting plane is orthogonal to the cone's axis...

 ogive. This is a curve very similar to the spitzer ogive, except that the circular arc is replaced by an ellipse defined in such a way that it meets the axis at exactly 90°. This gives a somewhat rounded nose regardless of the sharpness ratio. An elliptical ogive is normally described in terms of the ratio of the length of the ogive to the diameter of the shank. A ratio of one half would be, once again, a hemisphere. Values close to 1 are common in practice. Elliptical ogives are mainly used in pistol
Handgun
A handgun is a firearm designed to be held and operated by one hand. This characteristic differentiates handguns as a general class of firearms from long guns such as rifles and shotguns ....

 bullets.

Missiles and aircraft generally have much more complex ogives, such as the von Kármán ogive.

Architecture

One of the defining characteristics of Gothic architecture is the pointed or ogival arch. Arches of this type were used in the Near East
Near East
The Near East is a geographical term that covers different countries for geographers, archeologists, and historians, on the one hand, and for political scientists, economists, and journalists, on the other...

 in pre-Islamic as well as Islamic architecture
Islamic architecture
Islamic architecture encompasses a wide range of both secular and religious styles from the foundation of Islam to the present day, influencing the design and construction of buildings and structures in Islamic culture....

 before they were structurally employed in medieval architecture, and are thus thought to have been the inspiration for their use in France, as at Autun Cathedral, which is otherwise stylistically Romanesque.

In Gothic architecture
Gothic architecture
Gothic architecture is a style of architecture that flourished during the high and late medieval period. It evolved from Romanesque architecture and was succeeded by Renaissance architecture....

, ogives are the intersecting transverse ribs of arches that establish the surface of a Gothic vault
Vault (architecture)
A Vault is an architectural term for an arched form used to provide a space with a ceiling or roof. The parts of a vault exert lateral thrust that require a counter resistance. When vaults are built underground, the ground gives all the resistance required...

. An ogive or ogival arch is a pointed, "Gothic" arch
Arch
An arch is a structure that spans a space and supports a load. Arches appeared as early as the 2nd millennium BC in Mesopotamian brick architecture and their systematic use started with the Ancient Romans who were the first to apply the technique to a wide range of structures.-Technical aspects:The...

, drawn with compasses as outlined above, or with arcs of an ellipse as described. A very narrow, steeply pointed ogive arch (like the one in the construction above) is sometimes called a "lancet arch." The most common form is an equilateral arch, where the radius is the same as the width. In the later Flamboyant Gothic style, an "ogee arch," an arch delineating a void with a pointed head, like S-shaped curves, became prevalent.

Villard de Honnecourt
Villard de Honnecourt
Villard de Honnecourt was a 13th-century artist from Picardy in northern France. He is known to history only through a surviving portfolio of 33 sheets of parchment containing about 250 drawings dating from the 1220s/1240s, now in the Bibliothèque Nationale, Paris...

, a 13th century itinerant master-builder from the Picardy
Picardy
This article is about the historical French province. For other uses, see Picardy .Picardy is a historical province of France, in the north of France...

 in the north of France, was the first writer to use the word ogive. The OED
Oxford English Dictionary
The Oxford English Dictionary , published by the Oxford University Press, is the self-styled premier dictionary of the English language. Two fully bound print editions of the OED have been published under its current name, in 1928 and 1989. The first edition was published in twelve volumes , and...

considers the French term's origin obscure; it might come from the Late Latin
Late Latin
Late Latin is the scholarly name for the written Latin of Late Antiquity. The English dictionary definition of Late Latin dates this period from the 3rd to the 6th centuries AD extending in Spain to the 7th. This somewhat ambiguously defined period fits between Classical Latin and Medieval Latin...

 obviata, the feminine perfect passive participle of obviare, to resist, i.e. the arches resisting the downward force of the structure's mass.

Woodworking

In woodworking
Woodworking
Woodworking is the process of building, making or carving something using wood.-History:Along with stone, mud, and animal parts, wood was one of the first materials worked by early humans. Microwear analysis of the Mousterian stone tools used by the Neanderthals show that many were used to work wood...

, an ogive is a type of curve a piece of wood can be shaped in. See also: ogee
Ogee
An ogee is a curve , shaped somewhat like an S, consisting of two arcs that curve in opposite senses, so that the ends are parallel....


Statistics

In statistics
Statistics
Statistics is the study of the collection, organization, analysis, and interpretation of data. It deals with all aspects of this, including the planning of data collection in terms of the design of surveys and experiments....

, an ogive is a graph showing the curve of a cumulative distribution function
Cumulative distribution function
In probability theory and statistics, the cumulative distribution function , or just distribution function, describes the probability that a real-valued random variable X with a given probability distribution will be found at a value less than or equal to x. Intuitively, it is the "area so far"...

 (which, for the normal distribution, resembles one side of an Arabesque
Arabesque
The arabesque is a form of artistic decoration consisting of "surface decorations based on rhythmic linear patterns of scrolling and interlacing foliage, tendrils" or plain lines, often combined with other elements...

 or ogival arch).

Geology

In glaciology
Glaciology
Glaciology Glaciology Glaciology (from Middle French dialect (Franco-Provençal): glace, "ice"; or Latin: glacies, "frost, ice"; and Greek: λόγος, logos, "speech" lit...

, ogives are three dimensional wave-bulges characteristic of glaciers that have experienced extreme underlying topographical change, observed as an ice fall
Icefall
An icefall is a portion of some glaciers characterized by rapid flow and a chaotic crevassed surface. Perhaps the most conspicuous consequence of glacier flow, icefalls occur where the glacier bed steepens and/or narrows...

. Forbes bands are light and dark bands that appear down glacier ogives, resulting from different ice densities due to the seasons.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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