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Q:
Do the standard tennis balls of all tennis brands have the same amount of air pressure inside their tennis balls?
- Mira
Walnut, CA, US
A:
No. The USTA regulations only specify the pressure for special "pressure-less"balls, which use more rigid skins rather than air pressure. The rules say that that type of ball must have less than or equal to 1 psi (7 kPa) pressure (above atmospheric pressure). There are a number of other rules, for example, a ball dropped from a height of 100 inches must rebound between 53 and 58 inches, which apply to all tennis balls.
For all the gory details see Appendix I at the USTA site:
http://www.usta.com/2011_tennis_ball_specifications/
LeeH (mods by mbw)
(published on 01/04/2008)
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