Automobiles are vehicles that use a motor to propel themselves and carry passengers. They are used to transport people and goods over long distances. A car usually has four wheels and is powered by an internal combustion engine. There are many different types of automobiles. The branches of engineering that deal with the manufacture and technology of these vehicles are known as automotive engineering.
Until the invention of the automobile, humans relied on horses and other animals for transportation. When cars became available, they changed the way we live. Automobiles allow us to travel faster and farther than ever before. In addition, they allow people to spend more time with their families. They can also be useful in emergencies, such as when someone is ill or in need of medical assistance.
Automobiles have transformed cities and reshaped the landscape of America. They allow people to work, shop, and play virtually anywhere at any time. While some viewed this transformation as positive, others criticized it. In some cases, automobiles displaced public mass transit systems and encouraged suburban sprawl. They also undermined urban physical integrity and promoted a sense of exclusivity that favored some interests at the expense of the interest of the general population.
The earliest automobiles were steam-powered. Later, they were powered by electricity. Some of these were called electric cars, and they ran on traction batteries. In the 1860s, Siegfried Marcus invented an internal-combustion gasoline engine. He built a prototype in 1870 that had no seats, steering, or brakes. Nevertheless, it was the first practical automobile.
In the 1880s, Edouard Delamare-Deboutteville and Leon Malandin built a second automobile. They welded stamped components together to form a chassis, and they attached the engine to this frame. This vehicle did not survive its first test drive because of a loose fuel tank hose.
Today’s modern automobile is composed of thousands of parts. Like the human body, these are arranged into several semi-independent systems with different functions. The engine, the heart of the automobile, contains pistons, cylinders, tubes to circulate coolant fluid, and a fuel pump. The transmission, which connects the engine to the wheels, includes gears and a crank.
Another important system is the suspension, which allows the vehicle to ride over rough surfaces without shaking the passengers. It consists of springs, shock absorbers, and other components that are assembled in the framework of the chassis.
The body, made of steel or fiberglass, provides protection from accidents and the elements. It offers storage space and houses the automobile’s systems. Its front and hood are designed to crumple in the event of an accident, and the engine is protected by a firewall that separates the engine from the passenger compartment in case of fire. The chassis and other major systems are mounted on the body, which is welded to the chassis. The automobile industry revolutionized manufacturing through the introduction of the assembly line. This system allowed manufacturers to produce large numbers of identical cars at a lower cost. However, cars are a major source of greenhouse gases. The United States Environmental Protection Agency has estimated that transportation is responsible for 27 percent of the nation’s greenhouse gas emissions.