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Windage Loss
Windage is a term used in aerodynamics, firearms ballistics, and automobiles. Usage Aerodynamics Windage is a force created on an object by friction when there is relative movement between air and the object. Windage loss is the reduction in efficiency due to windage forces. For example, electric motors are affected by friction between the rotor and air. Large alternators have significant losses due to windage. To reduce losses, hydrogen gas may be used, since it is less dense. There are two causes of windage: # The object is moving and being slowed by resistance from the air. # A wind is blowing, producing a force on the object. The term can refer to: * The effect of the force, for example the deflection of a missile or an aircraft by a cross wind. * The area and shape of the object that make it susceptible to friction, for example those parts of a boat that are exposed to the wind. Aerodynamic streamlining can be used to reduce windage. There is a hydrodynamic effect si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Force
In physics, a force is an influence that can change the motion of an object. A force can cause an object with mass to change its velocity (e.g. moving from a state of rest), i.e., to accelerate. Force can also be described intuitively as a push or a pull. A force has both magnitude and direction, making it a vector quantity. It is measured in the SI unit of newton (N). Force is represented by the symbol (formerly ). The original form of Newton's second law states that the net force acting upon an object is equal to the rate at which its momentum changes with time. If the mass of the object is constant, this law implies that the acceleration of an object is directly proportional to the net force acting on the object, is in the direction of the net force, and is inversely proportional to the mass of the object. Concepts related to force include: thrust, which increases the velocity of an object; drag, which decreases the velocity of an object; and torque, which produce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elevation (ballistics)
In ballistics, the elevation is the angle between the horizontal plane and the axial direction of the barrel of a gun, mortar or heavy artillery. Originally, elevation was a ''linear'' measure of how high the gunners had to physically lift the muzzle of a gun up from the gun carriage to compensate for projectile drop and hit targets at a certain distance. Until WWI Though early 20th-century firearms were relatively easy to fire, artillery was not. Before and during World War I, the only way to effectively fire artillery was plotting points on a plane. Most artillery units seldom employed their guns in small numbers. Instead of using pin-point artillery firing they used old means of " fire for effect" using artillery en masse. This tactic was employed successfully by past armies. By World War I, reasonably accurate artillery fire was possible even at long range requiring significant elevation. However, artillery tactics used in previous wars were carried on, and still had simil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drag (physics)
In fluid dynamics, drag (sometimes called air resistance, a type of friction, or fluid resistance, another type of friction or fluid friction) is a force acting opposite to the relative motion of any object moving with respect to a surrounding fluid. This can exist between two fluid layers (or surfaces) or between a fluid and a solid surface. Unlike other resistive forces, such as dry friction, which are nearly independent of velocity, the drag force depends on velocity. Drag force is proportional to the velocity for low-speed flow and the squared velocity for high speed flow, where the distinction between low and high speed is measured by the Reynolds number. Even though the ultimate cause of drag is viscous friction, turbulent drag is independent of viscosity. Drag forces always tend to decrease fluid velocity relative to the solid object in the fluid's path. Examples Examples of drag include the component of the net aerodynamic or hydrodynamic force acting opposite to the di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deflection (ballistics)
{{unreferenced, date=May 2008 Deflection shooting is a technique of shooting ahead of a moving target, also known as leading the target, so that the projectile will "intercept" and collide with the target at a predicted point. This technique is only necessary when the target will have significantly displaced its position during the time the projectile would take to reach the target, which can become the case over very long distances (e.g. a long sniper shot), due to fast moving targets (e.g. aerial dogfight against an opposing aircraft, or anti-aircraft fire against passing aircraft), or while using relatively slow projectiles (e.g. a bolt shot from a crossbow, or a basketball thrown to a running teammate). Gyro gunsights developed for aircraft of the Second World War displayed a reticle that compensated for target lead. Modern fighter aircraft have automated deflection sights, where a computer calculates lead and projects the solution onto a head-up display (HUD). The visual assi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sump
A sump is a low space that collects often undesirable liquids such as water or chemicals. A sump can also be an infiltration basin used to manage surface runoff water and recharge underground aquifers. Sump can also refer to an area in a cave where an underground flow of water exits the cave into the earth. Examples One common example of a sump is the lowest point in a basement, into which flows water that seeps in from outside. If this is a regular problem, a sump pump that moves the water outside of the house may be used. Another example is the oil pan of an engine. The oil is used to lubricate the engine's moving parts and it pools in a reservoir known as its sump, at the bottom of the engine. Use of a sump requires the engine to be mounted slightly higher to make space for it. Often though, oil in the sump can slosh during hard cornering, starving the oil pump. For these reasons, racing motorcycles and piston aircraft engines are "dry sumped" using scavenge pumps and a s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crankshaft
A crankshaft is a mechanical component used in a piston engine to convert the reciprocating motion into rotational motion. The crankshaft is a rotating shaft containing one or more crankpins, that are driven by the pistons via the connecting rods. The crankpins are also called ''rod bearing journals'', and they rotate within the "big end" of the connecting rods. Most modern crankshafts are located in the engine block. They are made from steel or cast iron, using either a forging, casting or machining process. Design The crankshaft located within the engine block, held in place via main bearings which allow the crankshaft to rotate within the block. The up-down motion of each piston is transferred to the crankshaft via connecting rods. A flywheel is often attached to one end of the crankshaft, in order to smoothen the power delivery and reduce vibration. A crankshaft is subjected to enormous stresses, in some cases more than per cylinder. Crankshafts for single-cylin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internal Ballistics
Internal ballistics (also interior ballistics), a subfield of ballistics, is the study of the propulsion of a projectile. In guns, internal ballistics covers the time from the propellant's ignition until the projectile exits the gun barrel. The study of internal ballistics is important to designers and users of firearms of all types, from small-bore rifles and pistols, to high-tech artillery. For rocket-propelled projectiles, internal ballistics covers the period during which a rocket motor is providing thrust. Parts and equations Hatcher breaks the duration of interior ballistics into three parts: *Lock time, the time from sear release until the primer is struck *Ignition time, the time from when the primer is struck until the projectile starts to move *Barrel time, the time from when the projectile starts to move until it exits the barrel. There are many processes that are significant. The source of energy is the burning propellant. It generates hot gases that raise the chambe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cannon
A cannon is a large- caliber gun classified as a type of artillery, which usually launches a projectile using explosive chemical propellant. Gunpowder ("black powder") was the primary propellant before the invention of smokeless powder during the late 19th century. Cannons vary in gauge, effective range, mobility, rate of fire, angle of fire and firepower; different forms of cannon combine and balance these attributes in varying degrees, depending on their intended use on the battlefield. A cannon is a type of heavy artillery weapon. The word ''cannon'' is derived from several languages, in which the original definition can usually be translated as ''tube'', ''cane'', or ''reed''. In the modern era, the term ''cannon'' has fallen into decline, replaced by ''guns'' or ''artillery'', if not a more specific term such as howitzer or mortar, except for high-caliber automatic weapons firing bigger rounds than machine guns, called autocannons. The earliest known depict ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Musket
A musket is a muzzle-loaded long gun that appeared as a smoothbore weapon in the early 16th century, at first as a heavier variant of the arquebus, capable of penetrating plate armour. By the mid-16th century, this type of musket gradually disappeared as the use of heavy armour declined, but ''musket'' continued as the generic term for smoothbore long guns until the mid-19th century. In turn, this style of musket was retired in the 19th century when rifled muskets (simply called rifles in modern terminology) using the Minié ball (invented by Claude-Étienne Minié in 1849) became common. The development of breech-loading firearms using self-contained cartridges (introduced by Casimir Lefaucheux in 1835) and the first reliable repeating rifles produced by Winchester Repeating Arms Company in 1860 also led to their demise. By the time that repeating rifles became common, they were known as simply "rifles", ending the era of the musket. Etymology According to the Online Et ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Round Shot
A round shot (also called solid shot or simply ball) is a solid spherical projectile without explosive charge, launched from a gun. Its diameter is slightly less than the bore of the barrel from which it is shot. A round shot fired from a large-caliber gun is also called a cannonball. The cast iron cannonball was introduced by a French artillery engineer Samuel J. Besh after 1450; it had the capacity to reduce traditional English castle wall fortifications to rubble. French armories would cast a tubular cannon body in a single piece, and cannonballs took the shape of a sphere initially made from stone material. Advances in gunpowder manufacturing soon led the replacement of stone cannonballs with cast iron ones. Round shot was made in early times from dressed stone, referred to as gunstone (Middle English: ''gunneston''), but by the 17th century, from iron. It was used as the most accurate projectile that could be fired by a smoothbore cannon, used to batter the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muzzleloading
Muzzleloading is the shooting sport of firing muzzleloading guns. Muzzleloading guns, both antique and reproduction, are used for target shooting, hunting, historical re-enactment and historical research. The sport originated in the United States in the 1930s, just as the last original users and makers of muzzleloading arms were dying out. The sport received a tremendous boost in the 1960s and 1970s. The Muzzle Loaders Associations International Committee (www.MLAIC.org) was formed in 1970 and held its first World Championship in 1971. Since then a flourishing industry manufacturing working reproductions of historic firearms now exists in the United States and Europe, particularly in northern Italy, for example at Gardone Val Trompia, in the Province of Brescia. In the United States muzzleloading guns are, subject to a number of qualifications, generally not considered firearms. Subject to state law they may be possessed by persons who might otherwise not be legally allowed to own a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infobase Publishing
Infobase Publishing is an American publisher of reference book titles and textbooks geared towards the North American library, secondary school, and university-level curriculum markets. Infobase operates a number of prominent imprints, including Facts On File, Films for the Humanities & Sciences, Cambridge Educational, Chelsea House (which also serves as the imprint for the special collection series, "Bloom's Literary Criticism" under the direction of literary critic Harold Bloom), and Ferguson Publishing. History The private equity firm Veronis Suhler Stevenson bought Facts on File and Chelsea House in 2005. Infobase bought Films for the Humanities & Sciences in 2007 and the ''World Almanac'' in 2009. In 2017, Infobase acquired The Mailbox lesson plans and ''Learning'' magazine. Veronis Suhler Stevenson sold Infobase to another private equity firm, Centre Lane Partners, in 2018. As well as nonfiction works in print, Infobase and its imprints publish a selection of works in di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
