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Road transport

Road vehicles of all kindsMotor vehicles of all kinds, including cars, buses, lorries and motorcycles, all have the same basic features. Wheels and suspension allow the vehicle to roll smoothly along the road. Rubber tyres, inflated with air, give a comfortable ride. They also grip the road surface, allowing the vehicle to accelerate or brake without sliding about. Power from the vehicle’s engine, normally fuelled by petrol or diesel, turns the wheels. The exhaust system carries away waste gases. Recharged by the engine, the battery supplies electricity to the engine’s spark plugs, headlamps, radio and other electrical equipment.


The interior of a carA car is a small wheeled motor vehicle. It carries its own engine or motor and is used for transporting passengers. It usually has four wheels. Saloon cars have a separate boot, hatchbacks have room for luggage behind the back seat, while estate cars have a larger space for carrying extra loads. Some cars are specially designed for speed, including racing. There are about 600 million cars worldwide and the numbers are rising fast.

Engine power is often measured in units called “horsepower”, originally used to compare the pulling power of a steam engine to that of a carthorse. A typical modern car has a horsepower of 125 to 200.

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