Automobiles are wheeled vehicles that self-propel using a motor embedded in the vehicle itself. They are often used to transport people, but may also be useful for carrying cargo and other items.
The basic components of an automobile include: chassis, engine, transmission system, and body. The chassis consists of the engine, clutch, gearbox, propeller shaft, axles, and control system such as brakes and steering.
Cars are the primary form of family transportation in most parts of the world, where they account for about a quarter of all passenger cars and a third of all vehicle miles driven annually. In the United States, where 4.6 trillion kilometers (almost five trillion miles) of road are traveled each year, there are hundreds of different automobile models from which to choose.
Several kinds of automobile transmission systems are available. The gear ratios provide the tractive effort necessary to overcome the resistance faced by the automobile while running from rest.
Some of the important components of a transmission system are: a clutch, fluid coupling, and gears.
A clutch is a device that connects and disconnects the engine from the transmission system. It prevents jerky motion when sufficient power is applied and avoids stress on the vehicle as well as its passengers.
An automatic transmission is a kind of gear transmission in which the driver doesn’t have to change the gears manually. Its advantages are high speed and torque for acceleration, low fuel consumption, and a small size.