Discovery Science: Technology – Automobiles: Motor and Body

Technology  – Transport Technology

In the beginning of the 19th century, the steam engine became a great success. It revolutionized travel by enabling speeds seven times faster than a horse-drawn carriage. This revolution in speed continues today.

New challenges include improving vehicle safety, using alternative means of energy in automobile engineering, and integrating information and communication technology.

Physics and Technology – Technology – Automobiles: Motor and Body

By making transport power and mobility available to the individual, the invention of the automobile has had a profound influence on personal and social life, especially since it became affordable to the middle class.

The motor is the heart of the automobile, and its function is to produce kinetic energy by conversion of thermal energy and either electric or chemical energy into movement. Higher oil prices and stricter emission standards, together with a rising customer demand have all inspired the global automobile industry to begin exploring alternative energy sources.

These include biodiesel fuels (containing corn and soybean by-products), electric engines, and hybrid engines (utilizing both fuel and electricity).

Transmission and chassis

Between the motor and the steering wheel is the power transmission, which includes the clutch, manual transmission, power divider, drive shaft, and differential gear. These work in conjunction in order to relay, distribute, and regulate the energy produced by the engine.

This energy is transmitted through the transaxle to the chassis, which is subsequently responsible for transmitting that energy to the roadway through the tires, suspension, brakes, and steering mechanisms.


The body, or exterior, of the automobile provides visual appeal, but more importantly it is responsible for the safety of its passengers. Automobile bodies made of a single piece of metal, called unitized bodies, are common.

Recent improvements include a skeletal structure made of hollow sections, allowing the use of lighter materials while still retaining strength and rigidity. Aluminum, magnesium, and synthetic materials, in addition to steel, are now frequently used.

Automotive electronics

The electronic system of an automobile includes the ignition system, battery, starter, safety features, and security system.

It also offers modern convenience through optional comfort systems such as heated seats and digital accessories.


In gasoline engines, the fuel is finely sprayed and mixed with air in the carburetor, then forced into the cylinder and compressed by the piston.

A spark plug ignites the mixture, causing an explosion that drives the piston outward. In four-stroke motors, the piston injects the fuel and discharges spent gases.

Petrol motors allow for quicker cycling, but are less efficient.