Automobiles are a key component of modern society and provide many benefits for their owners. In the United States alone, there are over three trillion miles traveled each year in automobiles. The car has revolutionized transportation and created a number of industries. In addition, it has become a symbol of individual freedom and a defining aspect of American culture. The automobile has also stimulated participation in outdoor recreation and increased tourism-related businesses such as restaurants, motels and service stations. It has helped to end rural isolation and bring urban amenities such as schools and medical facilities to the countryside. It has helped to create new industries such as automobile manufacturing, steel and petroleum, and has helped to build highways and roads that have shaped the modern cityscape.
An automobile is a self-propelled motor vehicle designed primarily for the transport of passengers on land. It uses an internal combustion engine fueled with a volatile fuel, typically petrol or diesel. The automotive industry is one of the world’s largest and most universal technologies, with over 73 million cars produced in 2017 alone. It is a complex technical system comprising thousands of components with specific functions. These include body, chassis, engine, drivetrain, control systems and safety systems.
The development of the automobile was accelerated by the invention of the internal combustion engine, a device that transforms gasoline into kinetic energy and propels the car forward. The first practical gasoline-powered automobile was built by Gottlieb Daimler and Wilhelm Maybach in the 1890s. Daimler’s Stahlradwagen was powered by a four-stroke engine and had several innovative features, including a fluid coupling to transmit power between shafts. It was a more advanced design than Benz’s earlier model, which had only two-stroke engines.
Besides the internal combustion engine, other significant parts of an automobile are its transmission, wheels, and suspension. The transmission is a gear system that transmits torque between the driving and driven axles. This is important because speed and torque are inversely proportional, so high speeds require less horsepower than low speeds. The transmission is also equipped with a differential, which allows the rear to rotate at a different speed than the front, and a clutch, which disconnects the driving shaft from the driving one when there is excessive acceleration.
The safety of an automobile is ensured by various components, such as the airbag, seatbelts, and antilock braking systems. In addition, it is regulated by government agencies. The safety system of an automobile is continuously evolving as laws and technologies change. For example, some technologies, such as tire pressure monitoring and stability control, are becoming standard in more vehicles. Others, such as adaptive cruise control and lane-keeping assist, are becoming available on more affordable models as their associated costs decrease.