Low- to mid-priced tennis ball machine models include Lobster and Wilson, with prices ranging from a few hundred to over $1,000, as of 2015. Standard tennis ball machines can cost anywhere from $1,500 to $6,000, depending on the machine's specifications and features.
Tennis balls are made out of a hollow rubber core covered by a wool or nylon shell. In addition, the air inside the rubber core is pressurized so that the ball bounces evenly.
Some brands of tennis ball machines for dogs include Hyper, GoDogGo and iFetch. The Hyper dog ball launcher shoots balls up to 220 feet and comes with four tennis balls. It does not does not require assembly.
The Lobster Elite 3, SAM Model P4, Tennis Tower and Wilson Ball Machine are all highly rated, affordable tennis ball machines. The Lobster Elite 3 and Wilson Ball Machine are battery operated, while the Tennis Tower runs on 100 Watts AC. The SAM Model P4 runs on battery or AC.
An official tennis ball is between 2.575 inches and 2.7 inches in diameter as defined by the International Tennis Federation. Tennis balls also must conform to other criteria if they are to be used in regulation play.
The mass of a standard tennis ball is .057 kilograms. Mass is the measurement indicating the amount of matter in an object.
The official diameter of a tennis ball according to the International Tennis Federation must be between 2.575 and 2.7 inches. Tennis balls are sold in cylinders containing three per package.
Different surfaces provide varying degrees of friction or sliding force, which may affect the bounce of a tennis ball. The amount of friction that the tennis ball experiences depends largely on the coefficient of friction of the surface that it hits.
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