An automobile (or car) is a wheeled motor vehicle designed for passenger transportation. Most automobiles have four wheels and are powered by an internal combustion engine fueled most often by gasoline, a liquid petroleum product. In addition to an engine, most vehicles also have a chassis, suspension system, and braking systems, and a body. These major systems are designed to interact with and support each other, providing safety and comfort for passengers.
Automobiles are available in many shapes and sizes to suit different needs. Sports cars, for example, are designed to be fast and agile. Other popular automobiles include station wagons, which are large enough to carry families and cargo; convertibles, which allow drivers to enjoy the fresh air and sunshine; and trucks, which are designed to be rugged and reliable.
The history of automobiles began with the invention of the internal combustion engine, which powered vehicles by exploding fuel within a cylinder. Steam, electric, and gasoline internal combustion engines competed for decades until gasoline engines achieved dominance in the 1910s.
In 1870, Siegfried Marcus developed the world’s first automobile engine that used gasoline as fuel. However, he was unable to make it work, and the vehicle crashed during testing. The following year, Karl Benz built and patented a working automobile with a four-stroke gasoline engine. Although his initial vehicle was crude and had no seats or steering, Benz’s wife Bertha drove the automobile over a distance of more than 106 km (about 65 miles) in 1888. This event was an important step in demonstrating the practical usefulness of automobiles, and it gained considerable publicity, which boosted their popularity.
Since the 1920s, most cars have been mass-produced to meet demand. To keep production costs low, many manufacturers have used standardized parts, and automobiles sold by one manufacturer usually share mechanical parts with other cars produced by the same firm. This approach has benefited consumers, who can choose between different models and features, but it has made the automobile industry less competitive and innovative.
A COMPACT FUEL ENGINE
An automobile’s compact gasoline engine is a key component in its ability to provide high speed and torque for driving, and to maintain a constant speed for traveling. The engine’s small size and light weight also help to improve gas mileage, allowing the automobile to travel farther on a tank of gasoline.
An automobile’s transmission system allows it to accelerate and decelerate, changing the engine’s speed without requiring manual intervention from the driver. There are several types of transmission systems, but most have a fluid coupling that disengages the driven shaft from the driving shaft when the speed is too great. There are also a number of gears that adjust the speed and torque for different operating conditions. The higher the gear ratio, the faster the vehicle can run and the more power it will have. Gears are lubricated with oil to reduce friction between them.