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Wedge O^
A wedge is a triangular shaped tool, a portable inclined plane, and one of the six simple machines. It can be used to separate two objects or portions of an object, lift up an object, or hold an object in place. It functions by converting a force applied to its blunt end into forces perpendicular ( normal) to its inclined surfaces. The mechanical advantage of a wedge is given by the ratio of the length of its slope to its width..''McGraw-Hill Concise Encyclopedia of Science & Technology'', Third Ed., Sybil P. Parker, ed., McGraw-Hill, Inc., 1992, p. 2041. Although a short wedge with a wide angle may do a job faster, it requires more force than a long wedge with a narrow angle. The force is applied on a flat, broad surface. This energy is transported to the pointy, sharp end of the wedge, hence the force is transported. The wedge simply transports energy in the form of friction and collects it to the pointy end, consequently breaking the item. History Wedges have existed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indigenous Peoples Of The Americas
In the Americas, Indigenous peoples comprise the two continents' pre-Columbian inhabitants, as well as the ethnic groups that identify with them in the 15th century, as well as the ethnic groups that identify with the pre-Columbian population of the Americas as such. These populations exhibit significant diversity; some Indigenous peoples were historically hunter-gatherers, while others practiced agriculture and aquaculture. Various Indigenous societies developed complex social structures, including pre-contact monumental architecture, organized city, cities, city-states, chiefdoms, state (polity), states, monarchy, kingdoms, republics, confederation, confederacies, and empires. These societies possessed varying levels of knowledge in fields such as Pre-Columbian engineering in the Americas, engineering, Pre-Columbian architecture, architecture, mathematics, astronomy, History of writing, writing, physics, medicine, Pre-Columbian agriculture, agriculture, irrigation, geology, minin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
