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Monday, January 12, 2009
Motorcycle
A motorcycle (also called a motorbicycle, motorbike, bike, or cycle) is a single-track, two-wheeled motor vehicle powered by an engine. Motorcycles vary considerably depending on the task for which they are designed, such as long distance travel, navigating congested urban traffic, cruising, sport and racing, or off-road conditions. In many parts of the world, motorcycles are among the least expensive and most widespread forms of motorised transport. Traditionally, most motorcycles used less fuel than cars.
Electric
The first electric cars were built around 1832, well before internal combustion powered cars appeared. For a period of time electrics were considered superior due to the silent nature of electric motors compared to the very loud noise of the gasoline engine. This advantage was removed with Hiram Percy Maxim's invention of the muffler in 1897. Thereafter internal combustion powered cars had two critical advantages: 1) long range and 2) high specific energy (far lower weight of petrol fuel versus weight of batteries). The building of battery electric vehicles that could rival internal combustion models had to wait for the introduction of modern semiconductor controls and improved batteries. Because they can deliver a high torque at low revolutions electric cars do not require such a complex drive train and transmission as internal combustion powered cars. Some post-2000 electric car designs such as the Venturi Fétish are able to accelerate from 0-60 mph (96 km/h) in 4.0 seconds with a top speed around 130 mph (210 km/h). Others have a range of 250 miles (400 km) on the United States Environmental Protection Agency (EPA) highway cycle requiring 3-1/2 hours to completely charge. Equivalent fuel efficiency to internal combustion is not well defined but some press reports give it at around 135 miles per US gallon (1.74 L/100 km; 162 mpg-imp).
Diesel
Diesel-engined cars have long been popular in Europe with the first models being introduced in the 1930s by Mercedes Benz and Citroen. The main benefit of diesel engines is a 50% fuel burn efficiency compared with 27% in the best gasoline engines. A down-side of the Diesel engine is that better filters are required to reduce the presence in the exhaust gases of fine soot particulates called diesel particulate matter. Manufacturers are now starting to fit[when?] diesel particulate filters filters to remove the soot. Many diesel-powered cars can run with little or no modifications on 100% biodiesel and combinations of other organic oils.
Understanding Automobile
What is Automobile? An automobile or motor car is a wheeled motor vehicle for transporting passengers, which also carries its own engine or motor. Most definitions of the term specify that automobiles are designed to run primarily on roads, to have seating for one to eight people, to typically have four wheels, and to be constructed principally for the transport of people rather than goods. However, the term automobile is far from precise, because there are many types of vehicles that do similar tasks.
Etymology
The word automobile comes, via the French automobile, from the Ancient Greek word αὐτός (autós, "self") and the Latin mobilis ("movable"); meaning a vehicle that moves itself, rather than being pulled or pushed by a separate animal or another vehicle. The alternative name car is believed to originate from the Latin word carrus or carrum ("wheeled vehicle"), or the Middle English word carre ("cart") (from Old North French), or karros (a Gallic wagon).
Etymology
The word automobile comes, via the French automobile, from the Ancient Greek word αὐτός (autós, "self") and the Latin mobilis ("movable"); meaning a vehicle that moves itself, rather than being pulled or pushed by a separate animal or another vehicle. The alternative name car is believed to originate from the Latin word carrus or carrum ("wheeled vehicle"), or the Middle English word carre ("cart") (from Old North French), or karros (a Gallic wagon).
Saturday, January 10, 2009
Rocket and jet cars
A rocket car holds the record in drag racing. However, the fastest of those cars are used to set the Land Speed Record, and are propelled by propulsive jets emitted from rocket, turbojet, or more recently and most successfully turbofan engines. The ThrustSSC car using two Rolls-Royce Spey turbofans with reheat was able to exceed the speed of sound at ground level in 1997.
Gasoline
Gasoline engines have the advantage over diesel in being lighter and able to work at higher rotational speeds and they are the usual choice for fitting in high-performance sports cars. Continuous development of gasoline engines for over a hundred years has produced improvements in efficiency and reduced pollution. The carburetor was used on nearly all road car engines until the 1980s but it was long realised better control of the fuel/air mixture could be achieved with fuel injection. Indirect fuel injection was first used in aircraft engines from 1909, in racing car engines from the 1930s, and road cars from the late 1950s. Gasoline Direct Injection (GDI) is now starting to appear in production vehicles such as the 2007 (Mark II) BMW Mini. Exhaust gases are also cleaned up by fitting a catalytic converter into the exhaust system. Clean air legislation in many of the car industries most important markets has made both catalysts and fuel injection virtually universal fittings. Most modern gasoline engines also are capable of running with up to 15% ethanol mixed into the gasoline - older vehicles may have seals and hoses that can be harmed by ethanol. With a small amount of redesign, gasoline-powered vehicles can run on ethanol concentrations as high as 85%. 100% ethanol is used in some parts of the world (such as Brazil), but vehicles must be started on pure gasoline and switched over to ethanol once the engine is running. Most gasoline engined cars can also run on LPG with the addition of an LPG tank for fuel storage and carburettor modifications to add an LPG mixer. LPG produces fewer toxic emissions and is a popular fuel for fork-lift trucks that have to operate inside buildings.
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