The amazing world of flame balls, doughnuts and horseshoes

Flame balls are gentle and fragile spherical flames that up till recently could only exist in conditions of near-zero gravity. Researchers at TU/e have managed to observe flameballs at normal earth-bound conditions, and thus, ...

The birth of a subnanometer-sized soccer ball

Ever since the existence of molecules was proven and molecular reactions were predicted, humans have wanted to visually observe how such events proceed. Such observations of single-molecule reactions are highly important ...

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Ball

A ball is a round, usually spherical but sometimes ovoid, object with various uses. It is used in ball games, where the play of the game follows the state of the ball as it is hit, kicked or thrown by players. Balls can also be used for simpler activities, such as catch, marbles and juggling. Balls made from hard-wearing materials are used in engineering applications to provide very low friction bearings, known as ball bearings. Black powder weapons use stone and metal balls as projectiles.

Although many types of balls are today made from rubber, this form was unknown outside the Americas until after the voyages of Columbus. The Spanish were the first Europeans to see bouncing rubber balls (albeit solid and not inflated) which were employed most notably in the Mesoamerican ballgame. Balls used in various sports in other parts of the world prior to Columbus were made from other materials such as animal bladders or skins, stuffed with various materials.

As balls are one of the most familiar spherical objects to humans, the word "ball" is used to refer to, or to describe, anything spherical or near-spherical.

This text uses material from Wikipedia, licensed under CC BY-SA