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Braking Distance
A brake is a mechanical device that inhibits motion by absorbing energy from a moving system. It is used for slowing or stopping a moving vehicle, wheel, axle, or to prevent its motion, most often accomplished by means of friction. Background Most brakes commonly use friction between two surfaces pressed together to convert the kinetic energy of the moving object into heat, though other methods of energy conversion may be employed. For example, regenerative braking converts much of the energy to electrical energy, which may be stored for later use. Other methods convert kinetic energy into potential energy in such stored forms as pressurized air or pressurized oil. Eddy current brakes use magnetic fields to convert kinetic energy into electric current in the brake disc, fin, or rail, which is converted into heat. Still other braking methods even transform kinetic energy into different forms, for example by transferring the energy to a rotating flywheel. Brakes are generally a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disc Brake
A disc brake is a type of brake that uses the #Calipers, calipers to squeeze pairs of #Brake pads, pads against a disc (sometimes called a [brake] rotor) to create friction. There are two basic types of brake pad friction mechanisms: abrasive friction and adherent friction. This action slows the rotation of a shaft, such as a vehicle axle, either to reduce its rotational speed or to hold it stationary. The energy of motion is converted into heat, which must be dissipated to the environment. Hydraulic brakes, Hydraulically Actuator, actuated disc brakes are the most commonly used mechanical device for slowing motor vehicles. The principles of a disc brake apply to almost any rotating shaft. The components include the disc, master cylinder, and caliper, which contain at least one cylinder and two Brake pad, brake pads on both sides of the rotating disc. Design The development of disc-type brakes began in England in the 1890s. In 1902, the Lanchester Motor Company designed bra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shopping Cart
A shopping cart (American English), trolley (British English, Australian English), or buggy (Southern American English, Appalachian English), also known by a variety of #Name, other names, is a wheeled cart supplied by a Retail#Types of retail outlets, shop or store, especially supermarkets, for use by customers inside the premises for transport of merchandise as they move around the premises, while shopping, prior to heading to the checkout counter, checkout counter, cashiers or tills. Design Most modern shopping carts are made of metal or a combination of metal and plastic and have been designed to nest within each other in a line to facilitate collecting and moving many at one time and also to save on storage space. The carts can come in many sizes, with larger ones able to carry a child. There are also specialized carts designed for two children, and electric mobility scooters with baskets designed for individuals with disabilities. As of 2006, approximately 24,000 ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Automobile
A car, or an automobile, is a motor vehicle with wheels. Most definitions of cars state that they run primarily on roads, Car seat, seat one to eight people, have four wheels, and mainly transport private transport#Personal transport, people rather than cargo. There are around one billion cars in use worldwide. The French inventor Nicolas-Joseph Cugnot built the first steam-powered road vehicle in 1769, while the Swiss inventor François Isaac de Rivaz designed and constructed the first internal combustion-powered automobile in 1808. The modern car—a practical, marketable automobile for everyday use—was invented in 1886, when the German inventor Carl Benz patented his Benz Patent-Motorwagen. Commercial cars became widely available during the 20th century. The 1901 Oldsmobile Curved Dash and the 1908 Ford Model T, both American cars, are widely considered the first mass-produced and mass-affordable cars, respectively. Cars were rapidly adopted in the US, where they replac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vought F4U Corsair
The Vought F4U Corsair is an American fighter aircraft that saw service primarily in World War II and the Korean War. Designed and initially manufactured by Vought, Chance Vought, the Corsair was soon in great demand; additional production contracts were given to Goodyear Aerospace, Goodyear, whose Corsairs were designated FG, and Brewster Aeronautical Corporation, Brewster, designated F3A. The Corsair was designed and principally operated as a carrier-based aircraft, and entered service in large numbers with the U.S. Navy and Marines in World War II. It quickly became one of the most capable carrier-based fighter-bombers of the war. Some Japanese pilots regarded it as the most formidable American fighter and U.S. naval aviators achieved an 11:1 kill ratio. Early problems with carrier landings and logistics led to it being eclipsed as the dominant carrier-based fighter by the Grumman F6F Hellcat, powered by the same Pratt & Whitney R-2800 Double Wasp, Double Wasp engine first f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dive Bomber
A dive bomber is a bomber aircraft that dives directly at its targets in order to provide greater accuracy for the bomb it drops. Diving towards the target simplifies the bomb's trajectory and allows the pilot to keep visual contact throughout the bomb run. This allows attacks on point targets and ships, which were difficult to attack with conventional level bombers, even ''en masse''. Dive bombing was especially effective against vehicles when integrated into early instances of Blitzkrieg. After World War II, the rise of precision-guided munitions and improved anti-aircraft defences—both fixed gunnery positions and fighter interception—led to a fundamental change in dive bombing. New weapons, such as rockets, allowed for better accuracy from smaller dive angles and from greater distances. They could be fitted to almost any aircraft, including fighters, improving their effectiveness without the inherent vulnerabilities of dive bombers, which needed air superiority to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saab 17
The Saab 17 is a Sweden, Swedish single-engine monoplane reconnaissance dive-bomber aircraft of the 1940s originally developed by AB Svenska Järnvägsverkstädernas Aeroplanavdelning, ASJA prior to its merger into Saab AB , Saab. It was the first all-metal stressed skin aircraft developed in Sweden. Design and development The project was initiated in response to a 1938 request from the ''Flygvapnet'' (Swedish Air Force) for a reconnaissance aircraft to replace the obsolete Fokker C.V, Fokker S 6 (C.Ve) sesquiplane. Design work began at the end of the 1930s as the L 10 by AB Svenska Järnvägsverkstädernas Aeroplanavdelning, ASJA, but once accepted by the ''Flygvapnet'' it was assigned the designations B 17 and S 17 for the bomber and reconnaissance versions respectively, and it became better known as the Saab 17. The design chosen was a conventional mid-wing Cantilever#Aircraft, cantilever monoplane with a long greenhouse canopy and a single radial engine in the nose. Control ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dive Bombers
A dive bomber is a bomber aircraft that dives directly at its targets in order to provide greater accuracy for the bomb it drops. Diving towards the target simplifies the bomb's trajectory and allows the pilot to keep visual contact throughout the bomb run. This allows attacks on point targets and ships, which were difficult to attack with conventional level bombers, even ''en masse''. Dive bombing was especially effective against vehicles when integrated into early instances of Blitzkrieg. After World War II, the rise of precision-guided munitions and improved anti-aircraft defences—both fixed gunnery positions and fighter interception—led to a fundamental change in dive bombing. New weapons, such as rockets, allowed for better accuracy from smaller dive angles and from greater distances. They could be fitted to almost any aircraft, including fighters, improving their effectiveness without the inherent vulnerabilities of dive bombers, which needed air superiority to o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fighter Aircraft
Fighter aircraft (early on also ''pursuit aircraft'') are military aircraft designed primarily for air-to-air combat. In military conflict, the role of fighter aircraft is to establish air supremacy, air superiority of the battlespace. Domination of the airspace above a battlefield permits bombers and attack aircraft to engage in tactical bombing, tactical and strategic bombing of enemy targets, and helps prevent the enemy from doing the same. The key performance features of a fighter include not only its firepower but also its high speed and maneuverability relative to the target aircraft. The success or failure of a combatant's efforts to gain air superiority hinges on several factors including the skill of its pilots, the tactical soundness of its doctrine for deploying its fighters, and the numbers and performance of those fighters. Many modern fighter aircraft also have secondary capabilities such as ground-attack aircraft, ground attack and some types, such as fighter-b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the world's countries participated, with many nations mobilising all resources in pursuit of total war. Tanks in World War II, Tanks and Air warfare of World War II, aircraft played major roles, enabling the strategic bombing of cities and delivery of the Atomic bombings of Hiroshima and Nagasaki, first and only nuclear weapons ever used in war. World War II is the List of wars by death toll, deadliest conflict in history, causing World War II casualties, the death of 70 to 85 million people, more than half of whom were civilians. Millions died in genocides, including the Holocaust, and by massacres, starvation, and disease. After the Allied victory, Allied-occupied Germany, Germany, Allied-occupied Austria, Austria, Occupation of Japan, Japan, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glider Aircraft
A glider is a fixed-wing aircraft that is supported in flight by the dynamic reaction of the air against its lifting surfaces, and whose gliding flight, free flight does not depend on an engine. Most gliders do not have an engine, although motor-gliders have small engines for extending their flight when necessary by sustaining the altitude (normally a sailplane relies on rising air to maintain altitude) with some being powerful enough to take off by Motor glider, self-launch. There are a wide variety of types differing in the construction of their wings, aerodynamic efficiency, location of the pilot, controls and intended purpose. Most exploit lift (soaring), meteorological phenomena to maintain or gain height. Gliders are principally used for the air sports of gliding, hang gliding and paragliding. However some spacecraft have been designed to descend as gliders and in the past military gliders have been used in warfare. Some simple and familiar types of glider are toys such a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Brake (aircraft)
In aeronautics, air brakes, or speed brakes, are a type of flight control surface used on an aircraft to increase the drag on the aircraft. When extended into the airstream, air brakes cause an increase in the drag on the aircraft. When not in use, they conform to the local streamlined profile of the aircraft in order to help minimize drag. Air brakes differ from spoilers in that air brakes are designed to increase drag while making little change to lift, whereas spoilers reduce the lift-to-drag ratio and require a higher angle of attack to maintain lift, resulting in a higher stall speed. However, flight spoilers are routinely referred to as "speed brakes" on transport aircraft by pilots and manufacturers, despite significantly reducing lift. History In the early decades of powered flight, air brakes were flaps mounted on the wings. They were manually controlled by a lever in the cockpit, and mechanical linkages to the air brake. Another early type of air brake, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Landing Gear
Landing gear is the undercarriage of an aircraft or spacecraft that is used for taxiing, takeoff or landing. For aircraft, it is generally needed for all three of these. It was also formerly called ''alighting gear'' by some manufacturers, such as the Glenn L. Martin Company. For aircraft, Stinton makes the terminology distinction ''undercarriage (British) = landing gear (US)''. For aircraft, the landing gear supports the craft when it is not flying, allowing it to take off, land, and taxi without damage. Wheeled landing gear is the most common, with skis or Seaplane, floats needed to operate from snow/ice/water and skids for vertical operation on land. Retractable undercarriages fold away during flight, which reduces drag (physics), drag, allowing for faster airspeeds. Landing gear must be strong enough to support the aircraft and its design affects the weight, balance and performance. It often comprises three wheels, or wheel-sets, giving a tripod effect. Some unusual land ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
