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LET'S EXPLORE How things work

How are ships powered?

Ships and boats in a portShips and boats in a portShips are large vessels that travel across seas and oceans. Boats are smaller craft. Centuries ago, all ships were powered either by the wind or by oars. Most ships today are powered by engines that turn a propeller. Ships are used for carrying passengers or cargo, for fishing, harbour work, scientific research or for military purposes.


Different ships compared in sizeDifferent ships compared in size


The buoyancy force acting on a shipThe buoyancy force acting on a ship

Why a ship floats

Water pushes upwards on anything that is immersed in it. This is called buoyancy. Anything that is denser than water will sink, while objects less dense than water will float. A heavy metal ship floats because it contains lots of air, making it less dense than water.

Large container ships can carry up to 15,000 container boxes at once.

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