A tennis ball is a small, hollow ball used in games of tennis and real tennis. [1] Tennis balls are fluorescent yellow in professional competitions, [2] [3] but in recreational play other colors are also used. Tennis balls are covered in a fibrous felt, which modifies their aerodynamic properties, and each has a white curvilinear oval covering it.
Modern tennis balls must conform to certain size, weight, deformation, and bounce criteria to be approved for regulation play. The International Tennis Federation (ITF) defines the official diameter as 6.54–6.86 cm (2.57–2.70 inches). Balls must have masses in the range 56.0–59.4 g (1.98–2.10 ounces). A tennis ball generally has 12 pounds per square inch (80 kPa; 0.8 atm) more of a nitrogen and oxygen mixture than the sea level ambient air pressure. [4] [5] Yellow and white are the only colors approved by the ITF. Most balls produced are a fluorescent color known as "optic yellow", first introduced in 1972 following research demonstrating they were more visible on television. What color to call the ball is mildly controversial; one poll showed that a little less than half of people consider this color yellow, while a slight majority consider it green. [6]
Tennis balls are filled with air and are surfaced by a uniform felt-covered rubber compound. Tennis ball felts comprise wool, nylon, and cotton in a mixture surrounding the rubber edge. [7] The felt delays flow separation in the boundary layer which reduces aerodynamic drag and gives the ball better flight properties. [8] [9] Often, the balls will have a number in addition to the brand name. This helps distinguish one set of balls from another of the same brand on an adjacent court. [10]
Tennis balls begin to lose their bounce as soon as the tennis ball can is opened. Tennis balls lose bounciness because the air inside the ball is pushing harder when a can is opened compared to when a ball is packaged. When packaged, the pressure in the can equally pushes the ball from the outside as the air inside the balls, preserving the pressure inside. When a tennis ball is unpackaged, its frequent use allows for air to escape from the ball. [11] They can be tested to determine their bounce. Modern regulation tennis balls are kept under pressure (approximately two atmospheres) until initially used; balls intended for use at high altitudes have a lower initial pressure, and inexpensive practice balls are made without internal pressurization. A ball is tested for bounce by dropping it from a height of 254 cm (100 inches) onto concrete; a bounce between 135 and 147 cm (53 and 58 inches) is acceptable if taking place at sea-level and 20 °C (68 °F) with relative humidity of 60%; high-altitude balls have different characteristics when tested at sea level. [12]
The ITF's "Play and Stay" campaign aims to increase tennis participation worldwide by improving how starter players are introduced to the game. The ITF recommends a progression that focuses on a range of slower balls and smaller court sizes to introduce the game to adults and children effectively. The slowest balls, marked with red, or using half-red felt, are oversized and unpressurized or made from foam rubber. The next, in orange, are unpressurized normal-sized balls. The last, with green, are half pressured normal sized. [10]
Lawn tennis, as the modern game was originally known, was developed in the early 1870s as a new version of the courtly game of real tennis. England banned the importation of real tennis balls, playing cards, dice, and other goods in the Importation (No. 2) Act 1463 (3 Edw. 4. c. 4). [13] In 1480, Louis XI of France forbade the filling of tennis balls with chalk, sand, sawdust, or earth, and stated that they were to be made of good leather, well-stuffed with wool. [14] Other early tennis balls were made by Scottish craftsmen from a wool-wrapped stomach of a sheep or goat and tied with rope. Those recovered from the hammer-beam roof of Westminster Hall during a period of restoration in the 1920s were found to have been manufactured from a combination of putty and human hair and were dated to the reign of Henry VIII. [15] Other versions, using materials such as animal fur, rope made from animal intestines and muscles, and pine wood, were found in Scottish castles dating back to the 16th century.[ citation needed ] In the 18th century, 1.9 cm (3⁄4 in) strips of wool were wound tightly around a nucleus made by rolling several strips into a little ball. [16] String was then tied in many directions around the ball, and a white cloth covering was sewn around the ball.[ citation needed ]
In the early 1870s, lawn tennis arose in Britain through the pioneering efforts of Walter Clopton Wingfield and Harry Gem, often using Victorian lawns laid out for croquet. Wingfield marketed lawn tennis sets which included rubber balls imported from Germany. After Charles Goodyear invented vulcanised rubber, the Germans had been most successful in developing air-filled vulcanised rubber balls. These were light and coloured grey or red with no covering. John Moyer Heathcote suggested and tried the experiment of covering the rubber ball with flannel, and by 1882 Wingfield was advertising his balls as clad in stout cloth made in Melton Mowbray. [17] Tennis balls were initially entirely made of rubber, but they were later refined by using flannel and stitching it around the core, which used to be filled with rubber. The tennis ball quickly switched to having a hollow core, using gas to pressurize the inside. Originally, tennis ball manufacturing was done by cutting vulcanized rubber sheets into a shape similar to that of a three-leaf clover. Before the formation of the rubber into a sphere (which was executed via machinery), chemicals that reacted to produce a gas were added to produce pressure into the hollow inside once the sphere was assembled. The switch to the modern method of joining two hemispheres was done to improve uniformity of wall thickness. [18]
Until 1972, tennis balls were white (or sometimes black). In 1972, the International Tennis Federation introduced yellow balls, as these were easier to see on television, and these quickly became generally popular. Wimbledon continued using white balls until 1986. [18]
Importation (No. 2) Act 1463 | |
---|---|
Act of Parliament | |
Long title | Certain merchandises not lawful to be brought ready into this realm. |
Citation | 3 Edw. 4. c. 4 |
Dates | |
Commencement | 29 April 1463 |
Repealed | 10 August 1872 |
Other legislation | |
Repealed by | Statute Law Revision (Ireland) Act 1872 |
Status: Repealed |
Before 1925, tennis balls were packaged in wrapped paper and paperboard boxes. In 1925, Wilson-Western Sporting Goods Company introduced cardboard tubes. In 1926, the Pennsylvania Rubber Company released a hermetically sealed pressurized metal tube that held three balls with a churchkey to open the top. Beginning in the 1980s, plastic (from recycled PET) [19] cans with a full-top pull-tab seal and plastic lid fit three or four balls per can. Pressureless balls often come in net bags or buckets since they need not be pressure-sealed.
Each year approximately 325 million balls are produced, which contributes roughly 20,000 tonnes (22,000 short tons) of waste in the form of rubber that is not easily biodegradable. Historically, tennis ball recycling has not existed. Balls from The Championships, Wimbledon are now recycled to provide field homes for the nationally threatened Eurasian harvest mouse. [20]
The gift of tennis balls offered to Henry in Shakespeare's Henry V is portrayed as the final insult which re-ignites the Hundred Years' War between England and France. [21]
John Webster also refers to tennis balls in The Duchess of Malfi . [22]
A ball is a round object with several 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 or 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.
Tennis is a racket sport that is played either individually against a single opponent (singles) or between two teams of two players each (doubles). Each player uses a tennis racket strung with a cord to strike a hollow rubber ball covered with felt over or around a net and into the opponent's court. The object is to manoeuvre the ball in such a way that the opponent is not able to play a valid return. If a player is unable to return the ball successfully, the opponent scores a point.
A tennis court is the venue where the sport of tennis is played. It is a firm rectangular surface with a low net stretched across the centre. The same surface can be used to play both doubles and singles matches. A variety of surfaces can be used to create a tennis court, each with its own characteristics which affect the playing style of the game.
A football is a ball inflated with air that is used to play one of the various sports known as football. In these games, with some exceptions, goals or points are scored only when the ball enters one of two designated goal-scoring areas; football games involve the two teams each trying to move the ball in opposite directions along the field of play.
Squash tennis is an American variant of squash, one played with a ball and racquets that are more similar to the equipment used for lawn tennis, and with somewhat different rules. The game offers the complexity of squash and the speed of racquetball.
A billiard table or billiards table is a bounded table on which cue sports are played. In the modern era, all billiards tables provide a flat surface usually made of quarried slate, that is covered with cloth, and surrounded by vulcanized rubber cushions, with the whole thing elevated above the floor. More specific terms are used for specific sports, such as snooker table and pool table, and different-sized billiard balls are used on these table types. An obsolete term is billiard board, used in the 16th and 17th centuries.
Major Walter Clopton Wingfield was a Welsh inventor and a British Army officer who was one of the pioneers of lawn tennis. Inducted into the International Tennis Hall of Fame in 1997 as the founder of modern lawn tennis, an example of the original equipment for the sport and a bust of Wingfield can be seen at the Wimbledon Lawn Tennis Museum.
This page is a glossary of tennis terminology.
A bouncy ball or rubber ball is a spherical toy ball, usually fairly small, made of elastic material which allows it to bounce against hard surfaces. When thrown against a hard surface, bouncy balls retain their momentum and much of their kinetic energy. They can thus rebound with an appreciable fraction of their original force. Natural rubber originated in the Americas, and rubber balls were made before European contact, including for use in the Mesoamerican ballgame. Bouncy balls are a very common object of play. Christopher Columbus witnessed Haitians playing with a rubber ball in 1495.
A lacrosse ball is the solid rubber ball that is used, with a lacrosse stick, to play the sport of lacrosse. It is typically white for men's lacrosse, or yellow for women's lacrosse; but the balls are produced in a wide variety of colours.
Frontenis is a sport that is played in a 30 meter pelota court using racquets and rubber balls. It can be played in pairs or singles, but only pairs frontenis is played in international competitions. This sport was developed in Mexico around 1900, and is accredited as a Basque pelota speciality.
A football or soccer ball is the ball used in the sport of association football. The ball's spherical shape, as well as its size, weight, mass, and material composition, are specified by Law 2 of the Laws of the Game maintained by the International Football Association Board. Additional, more stringent standards are specified by FIFA and other big governing bodies for the balls used in the competitions they sanction.
A basketball is a spherical ball used in basketball games. Basketballs usually range in size from very small promotional items that are only a few inches in diameter to extra large balls nearly 2 feet (60 cm) in diameter used in training exercises. For example, a youth basketball could be 27 inches (69 cm) in circumference, while a National Collegiate Athletic Association (NCAA) men's ball would be a maximum of 30 inches (76 cm) and an NCAA women's ball would be a maximum of 29 inches (74 cm). The standard for a basketball in the National Basketball Association (NBA) is 29.5 inches (75 cm) in circumference and for the Women's National Basketball Association (WNBA), a maximum circumference of 28.5 inches (72 cm). High school and junior leagues normally use NCAA, NBA or WNBA sized balls.
The racket sport traditionally named lawn tennis, invented in Edgbaston, Warwickshire, England, now commonly known simply as tennis, is the direct descendant of what is now denoted real tennis or royal tennis, which continues to be played today as a separate sport with more complex rules.
The 1877 Wimbledon Championship was a men's tennis tournament held at the All England Croquet and Lawn Tennis Club in Wimbledon, London. It was the world's first official lawn tennis tournament, and was later recognised as the first Grand Slam tournament or "Major". The AEC & LTC had been founded in July 1868, as the All England Croquet Club. Lawn tennis was introduced in February 1875 to compensate for the waning interest in croquet. In June 1877 the club decided to organise a tennis tournament to pay for the repair of its pony roller, needed to maintain the lawns. A set of rules was drawn up for the tournament, derived from the first standardised rules of tennis issued by the Marylebone Cricket Club in May 1875.
The following outline is provided as an overview of and topical guide to tennis.
Penn Racquet Sports, Inc. is a subsidiary of Head N.V. that manufactures tennis balls and racquetballs. Penn was founded in 1910 as Pennsylvania Rubber Company of America, Inc. in Jeannette, Pennsylvania. Penn was acquired by Head N.V. in 1999 and is currently headquartered in Phoenix, Arizona.
10 and Under Tennis is a program that was introduced by the United States Tennis Association (USTA) in the summer of 2010. Upon making the change official in 2012, it modified the format of all USTA and International Tennis Federation (ITF) events involving players of years 10 and younger. The program changes the game making it easier for children to succeed. The objective is to adapt the court, balls, racket, and net to the size and strength level of youth players. These alternations create the opportunity for younger players to spend more time hitting balls rather than chasing them. It allows them to hone tennis skills and accelerate their development. The hope is that earlier success in tennis will translate to a lifetime of interest in the sport and perhaps set a foundation for generations of more world-class players.
Follis, or Ball of wind, a term used in the 15th and 16th centuries in Spain and Italy, was a hollow ball inflated with air under pressure, able to jump and bounce when impacting at a certain speed with any solid body. Different types of balls of wind were commonly used to play a variety of ball games that were popular in that particular period of time.
The physics of a bouncing ball concerns the physical behaviour of bouncing balls, particularly its motion before, during, and after impact against the surface of another body. Several aspects of a bouncing ball's behaviour serve as an introduction to mechanics in high school or undergraduate level physics courses. However, the exact modelling of the behaviour is complex and of interest in sports engineering.