Archery - the bow and arrow
Read the article below and decide which word is missing. None of the missing words are longer than five letters long.
The use of bow can traced back to the earliest civilizations, as witnessed writings and drawings from over the world. Drawings, biblical writings, and ancient cultures make references this tool and weapon. The bow and arrow shaped history, whether it be the plains of the ancient Roman and Greek battlefields, the defeat of the French army by English at Crecy in 1346, or the expansion of the American West. And, the sport archery is considered one of the oldest traditions.
Today, archery classified two areas: target and field. Target archery requires archers shoot specific number of arrows at different distances, set targets that established values. Field archery includes open-field target range archers shoot different arrows different targets or different distances around a course. simulates the type of shooting experienced while hunting.
The bow a simple machine, a two-arm spring. The archer stores energy bending the bow. This potential energy transferred to the arrow the form of kinetic energy the arrow is released.
Bows initially made from one material, usually wood, and were called self-bows. bows had difficulty handling the forces and stresses placed on them they were drawn. The stresses cause the bows break. Early hunters developed use of wood, horn, and sinew, glued together layers to increase the bow's tensile strength. These bows were called composite, because were made of two or more different materials. Today's bows are a combination of wood, fiberglass, lightweight metals, and high-technology materials. evolution of the bow continues the recurve design, the use of pulleys, and latest engineering research that the bow more efficient and easier to use.
Arrows undergone evolution of own. Early arrows were made of wood and were fletched primarily with the feathers such birds as eagle, crow, goose, and turkey. Most of today's arrows still made of wood, but some made from aluminum, fiberglass, and graphite. They are often fletched with feathers, although some more modern plastic veins.