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Hammer Throw At The World Athletics U20 Championships
A hammer is a tool, most often a hand tool, consisting of a weighted "head" fixed to a long handle that is swung to deliver an impact to a small area of an object. This can be, for example, to drive nails into wood, to shape metal (as with a forge), or to crush rock. Hammers are used for a wide range of driving, shaping, breaking and non-destructive striking applications. Traditional disciplines include carpentry, blacksmithing, warfare, and percussive musicianship (as with a gong). Hammering is use of a hammer in its strike capacity, as opposed to prying with a secondary claw or grappling with a secondary hook. Carpentry and blacksmithing hammers are generally wielded from a stationary stance against a stationary target as gripped and propelled with one arm, in a lengthy downward planar arc—downward to add kinetic energy to the impact—pivoting mainly around the shoulder and elbow, with a small but brisk wrist rotation shortly before impact; for extreme imp ...
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Claw-hammer
Clawhammer, sometimes called down-picking, overhand, or frailing, is a distinctive banjo playing style and a common component of American old-time music. The principal difference between clawhammer style and other styles is the picking direction. Traditional picking styles ( classic banjo), including those for folk, bluegrass, and classical guitar, consist of an up-picking motion by the fingers and a down-picking motion by the thumb; this is also the technique used in the Scruggs style for the banjo. Clawhammer picking, by contrast, is primarily a down-picking style. The hand assumes a claw-like shape and the strumming finger is kept fairly stiff, striking the strings by the motion of the hand at the wrist and/or elbow, rather than a flicking motion by the finger. In its most common form on the banjo, only the thumb and middle or index finger are used and the finger always downpicks, hitting the string with the back of the fingernail. By contrast, the thumb rests on the fifth ...
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Grappling
Grappling, in hand-to-hand combat, describes sports that consist of gripping or seizing the opponent. Grappling is used at close range to gain a physical advantage over an opponent, either by imposing a position or causing injury. Grappling is a broad term that encompasses many disciplines. These various martial arts can be practiced both as combat sports and for self-defense. Grappling contests often involve takedowns and ground control, and may end when a contestant concedes defeat, also known as a submission or tap out. Grappling most commonly does not include striking or the use of weapons. However, some fighting styles or martial arts known especially for their grappling techniques teach tactics that include strikes and weapons either alongside grappling or combined with it. Grappling appeared in the 1950s. Types of technique Grappling techniques can be broadly subdivided into clinch fighting; takedowns and throws; submission holds and pinning or controll ...
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North America
North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Caribbean Sea, and to the west and south by the Pacific Ocean. Because it is on the North American Plate, North American Tectonic Plate, Greenland is included as a part of North America geographically. North America covers an area of about , about 16.5% of Earth's land area and about 4.8% of its total surface. North America is the third-largest continent by area, following Asia and Africa, and the list of continents and continental subregions by population, fourth by population after Asia, Africa, and Europe. In 2013, its population was estimated at nearly 579 million people in List of sovereign states and dependent territories in North America, 23 independent states, or about 7.5% of the world's population. In Americas (terminology)#Human ge ...
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Claw Hammer
A claw hammer is a hammer primarily used in carpentry for driving nails into or pulling them from wood. Historically, a claw hammer has been associated with woodworking, but is also used in general applications. It is not suitable for heavy hammering on metal surfaces (such as in machining work), as the steel of its head is somewhat brittle; the ball-peen hammer is more suitable for such metalwork. An early claw hammer is seen in Albrecht Dürer's etching "Melencolia I," dated 1514, halfway up the left side. There are several nails in the lower right corner. Design A claw hammer is composed of a metal head and a handle, which historically was made of wood but also may be of steel, fiberglass, or other composite. One side of the head has a poll
Handtools for Trail Work, United States Forest Service with either a smooth or textured surface ...
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Framing (construction)
Framing, in construction, is the fitting together of pieces to give a structure support and shape. Framing materials are usually wood, engineered wood, or structural steel. The alternative to framed construction is generally called ''mass wall'' construction, where horizontal layers of stacked materials such as log building, masonry, rammed earth, adobe, etc. are used without framing. Building framing is divided into two broad categories, heavy-frame construction (heavy framing) if the vertical supports are few and heavy such as in timber framing, pole building framing, or steel framing; or light-frame construction (light-framing) if the supports are more numerous and smaller, such as balloon, platform, or light-steel framing. Light-frame construction using standardized dimensional lumber has become the dominant construction method in North America and Australia due to the economy of the method; use of minimal structural material allows builders to enclose a large area at mini ...
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Plastic
Plastics are a wide range of synthetic or semi-synthetic materials that use polymers as a main ingredient. Their plasticity makes it possible for plastics to be moulded, extruded or pressed into solid objects of various shapes. This adaptability, plus a wide range of other properties, such as being lightweight, durable, flexible, and inexpensive to produce, has led to its widespread use. Plastics typically are made through human industrial systems. Most modern plastics are derived from fossil fuel-based chemicals like natural gas or petroleum; however, recent industrial methods use variants made from renewable materials, such as corn or cotton derivatives. 9.2 billion tonnes of plastic are estimated to have been made between 1950 and 2017. More than half this plastic has been produced since 2004. In 2020, 400 million tonnes of plastic were produced. If global trends on plastic demand continue, it is estimated that by 2050 annual global plastic production will reach over 1, ...
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Haft
Haft may refer to: * Haft, another name for the hilt of a bayonet, knife, or sword * Haft, the shaft of an arrow, axe, or spear * The narrow constricted part of the standards (petals) and falls (sepals) near the center of the iris flower * Haft, Iran, a village in Razavi Khorasan Province, Iran *Hafting, the process by which an arrowhead, axehead, or spearhead is set into the wood. People with the surname * Herbert Haft (1920-2004), American businessman and father of businessman Robert Haft (see below) * Robert Haft Robert Michael Haft is an entrepreneur, primarily in health care, and became a household name in the Washington, D.C., Chicago, San Francisco, Houston, and Los Angeles markets for his Crown Books television commercial tagline, "Books cost too much ...
(20th century), American businessman {{disambiguation, surname ...
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Heat Treating
Heat treating (or heat treatment) is a group of industrial, thermal and metalworking processes used to alter the physical, and sometimes chemical, properties of a material. The most common application is metallurgical. Heat treatments are also used in the manufacture of many other materials, such as glass. Heat treatment involves the use of heating or chilling, normally to extreme temperatures, to achieve the desired result such as hardening or softening of a material. Heat treatment techniques include annealing, case hardening, precipitation strengthening, tempering, carburizing, normalizing and quenching. Although the term ''heat treatment'' applies only to processes where the heating and cooling are done for the specific purpose of altering properties intentionally, heating and cooling often occur incidentally during other manufacturing processes such as hot forming or welding. Physical processes Metallic materials consist of a microstructure of small crystals called "gra ...
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Steel
Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistant typically need an additional 11% chromium. Because of its high tensile strength and low cost, steel is used in buildings, infrastructure, tools, ships, trains, cars, machines, electrical appliances, weapons, and rockets. Iron is the base metal of steel. Depending on the temperature, it can take two crystalline forms (allotropic forms): body-centred cubic and face-centred cubic. The interaction of the allotropes of iron with the alloying elements, primarily carbon, gives steel and cast iron their range of unique properties. In pure iron, the crystal structure has relatively little resistance to the iron atoms slipping past one another, and so pure iron is quite ductile, or soft and easily formed. In steel, small amounts of carbon, other ...
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Golf Swing
The golf swing is the action by which players hit the ball in the sport of golf. The golf swing is a complex motion involving the whole body; the technicalities of the swing are known as golf stroke mechanics. There are differing opinions on what constitutes a "good" golf swing. In ''Work and Power Analysis of the Golf Swing'', Nesbit and Serrano suggest the golf swing has been studied by scientists and mathematicians who have developed various equations to help explain the complexity of the swing. It is generally agreed that a successful and consistent golf swing requires precise timing and mechanics, from the grip and position of one's fingers, to the position and movement of the feet. At any moment of the swing, whether back-swing, downswing, or upswing, something can go wrong that will throw off the whole body and result in a mishit. The entire swing motion should move on a plane in a fluid manner. The plane can be characterized as horizontal or vertical. Complex motion The g ...
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Club (weapon)
A club (also known as a cudgel, baton, bludgeon, truncheon, cosh, nightstick, or impact weapon) is a short staff or stick, usually made of wood, wielded as a weapon since prehistoric times. There are several examples of blunt-force trauma caused by clubs in the past, including at the site of Nataruk in Turkana, Kenya, described as the scene of a prehistoric conflict between bands of hunter-gatherers 10,000 years ago. Most clubs are small enough to be swung with one hand, although larger clubs may require the use of two to be effective. Various specialized clubs are used in martial arts and other fields, including the law-enforcement baton. The military mace is a more sophisticated descendant of the club, typically made of metal and featuring a spiked, knobbed, or flanged head attached to a shaft. Examples of cultural depictions of clubs may be found in mythology, where they are associated with strong figures such as Hercules or the Japanese oni, or in popular culture, where t ...
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