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Road transport


A car engineA car engineMost cars are powered by an internal combustion engine fuelled by petrol, diesel oil, hydrogen or biofuelsAn increasing number are powered by electric motors or are hybrids (combining an internal combustion engine with an electric propulsion system). In most cars, the engine is at the front, at right-angles to the direction in which the car travels. The driver makes the car go faster by pressing the accelerator (gas) pedal, which increases the power from the engine. The car slows when the brake pedal is pressed.

Working parts of a carWorking parts of a car

Basic features

All modern cars, from the smallest urban car to the fastest racing cars, have similar basic features. Wheels and suspension allow the car to roll smoothly along the road. Tyres on the wheels grip the road surface, allowing the car to accelerate, brake and corner without sliding. Power from the engine is transferred to the wheels by the transmission, including the gears.

In a car with an internal combustion engine, the fuel and exhaust systems supply fuel to the engine and carry away waste gases. The electrical system supplies electricity to the engine’s spark plugs, the car’s lights and other electrical gadgets. All the car’s parts are supported by a body shell, which also protects the driver and passengers.A cutaway illustration of a carA cutaway illustration of a carModern cars are fitted with seatbelts, side-impact bars and air bags to protect passengers if they crash. Anti-lock brakes reduce the risks of skidding. Most cars now have computerized engine management systems, which control the flow of fuel to the engine, and navigation computers (satnav) which give the driver directions. Many of these features were originally developed to improve the performance of racing cars, but have become standard on road cars.

Computer-aided aerodynamic designComputer-aided aerodynamic design


The US inventor Mary Anderson created the first modern-style windscreen wiper in 1903. It was operated by a lever from inside the car.

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