HOME TheInfoList
 picture info Motor An engine or motor is a machine designed to convert one form of energy into mechanical energy.[1][2] Heat engines, like the internal combustion engine, burn a fuel to create heat which is then used to do work. Electric motors convert electrical energy into mechanical motion, pneumatic motors use compressed air, and clockwork motors in wind-up toys use elastic energy. In biological systems, molecular motors, like myosins in muscles, use chemical energy to create forces and ultimately motion. The word engine derives from Old French engin, from the Latin ingenium–the root of the word ingenious. Pre-industrial weapons of war, such as catapults, trebuchets and battering rams, were called siege engines, and knowledge of how to construct them was often treated as a military secret. The word gin, as in cotton gin, is short for engine [...More Info...]       [...Related Items...] Latin Latin (latīnum, [laˈtiːnʊ̃] or lingua latīna, [ˈlɪŋɡʷa laˈtiːna]) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally spoken in the area around Rome, known as Latium.[4] Through the power of the Roman Republic, it became the dominant language in Italy, and subsequently throughout the western Roman Empire. Latin has contributed many words to the English language. In particular, Latin (and Ancient Greek) roots are used in English descriptions of theology, the sciences, medicine, and law. It is the official language in the Holy See (Vatican City). By the late Roman Republic (75 BC), Old Latin had been standardised into Classical Latin. Vulgar Latin was the colloquial form spoken during the same time and attested in inscriptions and the works of comic playwrights like Plautus and Terence[5] and author Petronius [...More Info...]       [...Related Items...] picture info Catapult A catapult is a ballistic device used to launch a projectile a great distance without the aid of gunpowder or other propellants – particularly various types of ancient and medieval siege engines.[1] A catapult uses the sudden release of stored potential energy to propel its payload. Most convert tension or torsion energy that was more slowly and manually built up within the device before release, via springs, bows, twisted rope, elastic, or any of numerous other materials and mechanisms. The counterweight trebuchet is a type of catapult that uses gravity.[2] In use since ancient times, the catapult has proven to be one of the most persistently effective mechanisms in warfare [...More Info...]       [...Related Items...] picture info Siege Engine A siege engine is a device that is designed to break or circumvent heavy castle doors, thick city walls and other fortifications in siege warfare. Some are immobile, constructed in place to attack enemy fortifications from a distance, while others have wheels to enable advancing up to the enemy fortification. There are many distinct types, such as siege towers that allow foot soldiers to scale walls and attack the defenders, battering rams that damage walls or gates, and large ranged weapons (such as ballistae, catapults/trebuchets and other similar constructions) that attack from a distance by launching projectiles. Some complex siege engines were combinations of these types. Siege engines are fairly large constructions – from the size of a small house to a large building [...More Info...]       [...Related Items...] picture info Torque In physics and mechanics, torque is the rotational equivalent of linear force.[1] It is also referred to as the moment, moment of force, rotational force or turning effect, depending on the field of study. The concept originated with the studies by Archimedes of the usage of levers. Just as a linear force is a push or a pull, a torque can be thought of as a twist to an object around a specific axis. Another definition of torque is the product of the magnitude of the force and the perpendicular distance of the line of action of a force from the axis of rotation. The symbol for torque is typically ${\displaystyle {\boldsymbol {\tau }}}$, the lowercase Greek letter tau [...More Info...]       [...Related Items...] picture info Combustion Combustion, or burning,[1] is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combustion does not always result in fire, but when it does, a flame is a characteristic indicator of the reaction. While the activation energy must be overcome to initiate combustion (e.g., using a lit match to light a fire), the heat from a flame may provide enough energy to make the reaction self-sustaining. Combustion is often a complicated sequence of elementary radical reactions. Solid fuels, such as wood and coal, first undergo endothermic pyrolysis to produce gaseous fuels whose combustion then supplies the heat required to produce more of them. Combustion is often hot enough that incandescent light in the form of either glowing or a flame is produced [...More Info...]       [...Related Items...] picture info Fluid Mechanics Fluid mechanics is the branch of physics concerned with the mechanics of fluids (liquids, gases, and plasmas) and the forces on them.[1]:3 It has applications in a wide range of disciplines, including mechanical, civil, chemical and biomedical engineering, geophysics, oceanography, meteorology, astrophysics, and biology. It can be divided into fluid statics, the study of fluids at rest; and fluid dynamics, the study of the effect of forces on fluid motion.[1]:3 It is a branch of continuum mechanics, a subject which models matter without using the information that it is made out of atoms; that is, it models matter from a macroscopic viewpoint rather than from microscopic. Fluid mechanics, especially fluid dynamics, is an active field of research, typically mathematically complex. Many problems are partly or wholly unsolved and are best addressed by numerical methods, typically using computers [...More Info...]       [...Related Items...]