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Wednesday, April 17, 2013

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The oldest boats found by archaeological excavation are logboats from around 7,000–9,000 years ago, a 7,000-year-old seagoing boat made from reeds and tar has been found in Kuwait.
Boats were used between 4000BCE-3000BCE in Sumer, ancient Egypt and in the Indian Ocean.
There is evidence of camel pulled wheeled vehicles about 3000–4000 BCE.
The earliest evidence of a wagonway, a predecessor of the railway, found so far was the 6 to 8.5 km (4 to 5 mi) long Diolkos wagonway, which transported boats across the Isthmus of Corinth in Greece since around 600 BC. Wheeled vehicles pulled by men and animals ran in grooves in limestone, which provided the track element, preventing the wagons from leaving the intended route.
In 200 CE, Ma Jun built a south-pointing chariot, a vehicle with an early form of guidance system.
Railways began reappearing in Europe after the Dark Ages. The earliest known record of a railway in Europe from this period is a stained-glass window in the Minster of Freiburg im Breisgau dating from around 1350.
    In 1515, Cardinal Matthäus Lang wrote a description of the Reisszug, a funicular railway at the Hohensalzburg Castle in Austria. The line originally used wooden rails and a hemp haulage rope and was operated by human or animal power, through a treadwheel
    1769 Nicolas-Joseph Cugnot is often credited with building the first self-propelled mechanical vehicle or automobile in about 1769, by adapting an existing horse-drawn vehicle, this claim is disputed by some[citation needed], who doubt Cugnot's three-wheeler ever ran or was stable.
    In Russia, in the 1780s, Ivan Kulibin developed a human-pedalled, three-wheeled carriage with modern features such as a flywheel, brake, gear box and bearings; however, it was not developed further.
    1783 Montgolfier brothers first Balloon vehicle
    1801 Richard Trevithick built and demonstrated his Puffing Devil road locomotive, which many believe was the first demonstration of a steam-powered road vehicle, though it could not maintain sufficient steam pressure for long periods and was of little practical use.
    1817 Push bikes, draisines or hobby horses were the first human means of transport to make use of the two-wheeler principle, the draisine (or Laufmaschine, "running machine"), invented by the German Baron Karl von Drais, is regarded as the forerunner of the modern bicycle (and motorcycle). It was introduced by Drais to the public in Mannheim in summer 1817.
Automobiles are among the most commonly used engine-powered vehicles
    1885 Karl Benz built (and subsequently patented) the first automobile, powered by his own four-stroke cycle gasoline engine in Mannheim, Germany
    1885 Otto Lilienthal began experimental gliding and achieved the first sustained, controlled, reproducible flights.
    1903 Wright brothers flew the first controlled, powered aircraft
    1907 First helicopters Gyroplane no.1 (tethered) and Cornu helicopter (free flight)[20]
    1928 Opel RAK.1 rocket car
    1929 Opel RAK.1 rocket glider
    1961 Vostok vehicle carried first man, Yuri Gagarin, into space
    1969 Apollo Program first manned vehicle landed on the moon
    2010 The number of road motor vehicles in operation worldwide surpassed the 1 billion mark – roughly one for every seven people.
Most popular vehicles
The most common model of vehicle in the world, the Flying Pigeon bicycle.
There are over 1 billion bicycles in use worldwide. According to 2002 estimates, there are around 590 million cars in service in the world and 205 million motorcycles.The most popular vehicle model in history is the Chinese Flying Pigeon bicycle, with on the order of 500 million in service.The most popular motor vehicle is the Honda Super Cub motorcycle, having passed 60 million units in 2008. The top selling car in history is the Toyota Corolla, with at least 35 million produced.
Locomotion
Main article: propulsion
Locomotion is achieved by being towed by another vehicle or animal or by obtaining, converting and using energy. Hybrid and tribrid vehicles have more complicated designs that employ several different paths for energy to take before being used.
Energy source
An electric bike in China
Main article: Energy storage#Storage methods
It is essential that a vehicle have a source of energy to drive it. Energy can be extracted from the surrounding environment, as in the case of a sailboat, a solar powered car or a streetcar. Energy can also be stored, in any form, provided it can be converted on demand and the storing medium's energy density and power density are sufficient to meet the vehicle's needs.
The most common type of energy source is fuel. External combustion engines can use almost anything that burns as fuel whilst internal combustion engines and rocket engines are tailor built to burn a specific fuel, typically gasoline, diesel or ethanol.
Another common medium for storing energy are batteries. Batteries have the advantage of being responsive, useful in a wide rage of power levels, environmentally friendly, efficient, simple to install and easy to maintain. Batteries also facilitate the use of electric motors, which have their own advantages. On the other hand, batteries have low energy densities, short service life, poor performance at extreme temperatures, long charging times and difficulties with disposal (although they can usually be recycled). like fuel, batteries store chemical energy and can cause burns and poisoning in event of an accident. Batteries also loose effectiveness with time. The issue of charge time can be resolved by swapping discharged batteries with charged ones, however this incurs additional hardware cost and may be impractical for larger batteries. Moreover, there must be standard batteries for battery swapping to work at a gas station. Fuel cells are similar to batteries in that they convert from chemical to electrical energy, but have their own set of advantages and disadvantages.
Electrified rails and overhead cables are a common source of electrical energy on subways, railways, trams, and trolleybuses. Solar energy is a more modern development, and several solar vehicles have been successfully built and tested, including Helios, a solar powered aircraft.
Nuclear power is a more exclusive form of energy storage, currently reserved for large ships and submarines, mostly military. Nuclear energy can be released by a nuclear reactor, nuclear battery or by repeatedly detonating nuclear bombs. There have been two experiments with nuclear-powered aircraft, the Tupolev Tu-119 and the Convair X-6.
Mechanical strain is another method of storing energy, where an elastic band or metal spring is deformed and releases energy as it is allowed to return to its ground state. Systems employing elastic materials suffer from hysteresis, and metal springs are too dense to be useful in many cases.[clarification needed]
Flywheels store energy in a spinning mass. Because a light and fast rotor is energetically favorable, flywheels can pose a significant safety hazard. Moreover, flywheels leak energy fairly quickly and effect a vehicle's steering due to the gyroscopic effect. They have been used experimentally in gyrobuses.
Wind energy is used by sailboats and land yachts as the primary source of energy. It is very cheap and fairly easy to use, the main issues being dependence on weather and upwind performance. Balloons also rely on the wind to move horizontally. Aircraft flying in the jet stream may get a boost from high altitude winds.
Compressed gas is currently an experimental method of storing energy. In this case, compressed gas is simply stored in a tank and released when necessary. Like elastics, they have hysteresis losses when gas heats up during compression.
Gravitational potential energy is a form of energy used in gliders, skis, bobsleds and numerous other vehicles that go down hill. Regenerative braking is an example of capturing kinetic energy where the brakes of a vehicle are augmented with a generator or other means of extracting energy.
Human power is a simple source of energy that requires nothing more than humans. Despite the fact that humans cannot exceed 500 W (0.67 hp) for meaningful amounts of time, the land speed record for human powered vehicles (unpaced) is 133 km/h (83 mph), as of 2009.
Motors and engines,Main article: Engine When needed, the energy is taken from the source and consumed by one or more motors or engines. Sometimes there is an intermediate medium, such as the batteries of a diesel submarine.
Most motor vehicles have internal combustion engines. They are fairly cheap, easy to maintain, reliable, safe and small. Since IC engines burn fuel, they have long ranges but pollute the environment. A related engine is the external combustion engine. An example of this are steam engines. Aside from fuel, steam engines also need water, making them impractical for some purposes. Steam engines also need time to warm up, whereas IC engines can usually run right after being started, although this is not recommended in cold conditions. Steam engines burning coal release sulfer into the air causing harmful acid rain.
A modern scooty in India.
While intermittent internal combustion engines were once the primary means of aircraft propulsion, they have been largely superseded by continuous internal combustion engines: gas turbines. Turbine engines are light and, particularly when used on aircraft, efficient.[citation needed] On the other hand, they cost more and require careful maintenance. They also get damaged from ingesting foreign objects and produce a hot exhaust. Trains using turbines are called gas turbine-electric locomotives. Examples of surface vehicles using turbines include M1 Abrams, MTT Turbine SUPERBIKE and the Millennium. Pulse jet engines are similar in many ways to turbojets, but have almost no moving parts. For this reason, they were very appealing to vehicle designers in the past, however their noise, heat and inefficiency has lend their abandonment. A historical example of a pulse jet in use was the V-1 flying bomb. Pulse jets are still occasionally used in amateur experiments. With the advent of modern technology, the pulse detonation engine has become practical and was successfully tested on a Rutan VariEze. While the pulse detonation engine is much more efficient that the pulse jet and even turbine engines, it still suffers from extreme noise and vibration levels. Ramjets also have few moving parts, but they only work at high speed meaning that their use is restricted to tip jet helicopters and high speed aircraft such as the Lockheed SR-71 Blackbird..

Car Wallpaper Hd Free Wallpaper Pics Pictures Hd for Desktop Iphone 

Car Wallpaper Hd Free Wallpaper Pics Pictures Hd for Desktop Iphone 

Car Wallpaper Hd Free Wallpaper Pics Pictures Hd for Desktop Iphone 

Car Wallpaper Hd Free Wallpaper Pics Pictures Hd for Desktop Iphone 

Car Wallpaper Hd Free Wallpaper Pics Pictures Hd for Desktop Iphone 

Car Wallpaper Hd Free Wallpaper Pics Pictures Hd for Desktop Iphone 

Car Wallpaper Hd Free Wallpaper Pics Pictures Hd for Desktop Iphone 

Car Wallpaper Hd Free Wallpaper Pics Pictures Hd for Desktop Iphone 

Car Wallpaper Hd Free Wallpaper Pics Pictures Hd for Desktop Iphone 

Car Wallpaper Hd Free Wallpaper Pics Pictures Hd for Desktop Iphone 

Car Wallpaper Hd Free Wallpaper Pics Pictures Hd for Desktop Iphone 

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