|Having a ball at Wimbledon!|
|Around the Academy:
Tennis balls - they're small, round, brightly coloured and bouncy.
What else is there to know? Well, quite a lot actually!
Let the Sport Academy put a spin on tennis ball technology...
What are tennis balls made of?
Modern tennis balls are made of a hollow rubber core, covered in a wool or nylon shell which is known as the nap.
Pressurised air inside the rubber core makes the ball bounce.
Balls which haven't got enough pressure inside make a thud when they hit the floor. These are called dead balls.
For the first Wimbledon tournament in 1902 balls were hand stitched - which meant no two balls ever bounced the same way.
These days, a heated press is used to bind the cloth to the core. This is how the seam (the white markings on the ball) is created.
If all the cloth used to make the balls during Wimbledon was laid out, it would cover a pitch the size of the Millennium Stadium!
Do the balls differ depending on the tournament?
Yes. Different tournaments are played on different surfaces.
The surface of the court will affect the speed and bounce of the ball, so the weight and compression will differ slightly.
The cloth also has to be more durable on abrasive surfaces such as hard court and clay.
In tournaments, all balls have to be white or yellow in colour.
How many balls are used at Wimbledon each year?
This year, Slazenger is supplying 52,200 tennis balls to Wimbledon.
About 20,000 of these are used for qualifying and practice.
Every single ball will have been individually hand tested for bounce, weight and compression.
That's because according to strict tennis rules, the ball must bounce between 53 and 58 inches after being dropped onto concrete from a height of 100 inches.
Each ball must also measure two-and-a-half inches (6.35cms) in diameter and weigh two ounces (56.7g).
Does size really matter?
Actually, the sport's governing body, the International Tennis Federation, is looking into the possibility of using larger tennis balls on fast courts like the ones at Wimbledon.
That's because a lot of people think tennis is simply getting too fast - which makes it boring to watch.
Hard hitters such as Andy Roddick can win matches on the strength of their serves alone, cutting down the number of rallies in a match.
One way of slowing the game down would be to make the balls bigger.
The bigger the ball, the slower it travels through the air.
New balls please! But why?
When balls lose pressure and get fluffed up they're not as bouncy.
This usually starts to happen after around three hours of play and can affect a player's control and accuracy.
That's why the balls are changed every seven and nine games alternately (after the first seven, the next nine, next seven and so on throughout the match).
The spare balls are stored in a refrigerated container at the side of the courts.
The balls are kept at 68° farenheit to keep them in perfect condition.
So what happens to the balls after they've been used at Wimbledon?
The balls are sold at the All England Tennis Club and funds raised are donated to charities such as the Balls for Schools scheme which helps support the tennis stars of the future.
Two years ago, 350 balls were donated to the Wildlife Trust who used them as nest boxes for harvest mice!