| Since the skills of the float serves came out, a lot of manpower and material resources have been launched into researches by several countries, but the researches' results are still uncertain, especially there isn't any report on mechanical factors affecting the float serves and the researches from practices. As a result of this situation, this article concentrated on the subjects of the balls used in the Chinese volleyball league matches and the float serves skills' application in Chinese women volleyball teams, to find out the floating distances and characteristics by wind tunnel experiments under the circumstances of different wind speeds, different air pressures and ball's symmetry or not. And according to the video record of the Ninth World Cup Women Volleyball Games in 2003, we analyze the status of the applications of floating serves skills, and also examine all the data. Drawing the following conclusion:1. The floating distances will be increase, then decrease and then increase with the increasing of wind speed under the same air pressure, and reach the maximum speed at 10m/s-15m/s. The maximum is about 0.5-0.6m.2. When the maximum floating serves come out, the critical speed is 10m/s-15m/s under the circumstances of different air pressure. When the wind speed become slower, the serves still float, and the floating distances become shorter.3. The difference of the floating distance between ball's symmetry or not is not obvious. It's only different at floating characteristics.4. There is obvious difference between the float serves skill's application in destroying attack and mistaking and jump serves skill's application in Chinese women volleyball team.5. When the Chinese women volleyball team use the floating serves skills, the down point area of the volleyball must be various in order to score or destroy attack.6. Chinese women volleyball team can try to floating serves' training by the different floating distance and unsymmetrical with the various speed of the volleyball.
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