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In North America, the term football refers to a prolate spheroid ball which is used to play American football or Canadian football. It is about 11 inches (28 centimeters) long and about 7 inches (18 centimeters) in diameter at the center. Balls are made of four pieces of leather stitched together. A football has a rubber lining, which is inflated to an air pressure of 12 1/2 to 13 1/2 pounds per square inch (0.88 to 0.95 kilogram per square centimeter). The ball weighs 14 to 15 ounces (397 to 425 grams). Leather laces along one seam provide a grip for holding and passing the ball. Footballs used in recreation may be made of rubber or plastic as well.
The ball used in Association football ( is a leather ball with which the sport football (soccer) is played. The traditional football's outer covering consists of 12 pentagons and 20 hexagons of leather sewn together. The ball is like the corresponding polyhedronIn mathematics, there are three related meanings of the term polyhedron: in the traditional meaning it is a 3-dimensional polytope, and in a newer meaning that exists alongside the older one it is a bounded or unbounded generalization of a polytope of any (designated a truncated icosahedronThe truncated icosahedron is an Archimedean solid. It has the same shape as a football (US: soccer ball) or a 60- carbon fullerene. Canonical coordinates for the vertices of a truncated icosahedron centered at the origin are the orthogonal rectangles (0,±, see picture there), except that it is more spherical, because the faces bulge due the pressure of the air inside.
It is a model for the buckminsterfullereneFullerenes are molecules composed entirely of carbon, taking the form of a hollow sphere, ellipsoid, tube, ring, or plane. They are sometimes called buckyballs . The molecule was named for Richard Buckminster Fuller, a noted architect who created the geod (C60) molecule. The diameter of the football and this buckyball are 22 cm and ca. 1 nmA nanometre ( American spelling: nanometer is 10−9 metres—or one billionth of a metre. Its symbol is nm . It is an SI measure of length, commonly used in measuring the wavelengths of visible light, ultraviolet radiation and gamma rays; amongst other, respectively, hence the size ratio is 200,000,000 : 1.
Other designs for footballs exist, mainly being made up of curved strips of leather. There are also indoor footballs, which are made of one or two pieces of plastic. Often these have designs printed on them to resemble a traditional leather ball.
The now familiar black pentagon/white hexagon combination, called the Telstar, became the standard design for most soccer balls since Adidas introduced it to the MexicoThis article is about the country Mexico. For other meanings, see Mexico (disambiguation The United Mexican States or Mexico ( Spanish: Estados Unidos Mexicanos or Mexico regarding the use of the variant spelling Mejico see section The name below) is a co World Cup in 1970. However, the new Nike GEO Merlin is currently the official ball of the English Premiership due to its lightweight properties enabling more spin on the ball.