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Measurement of Surface Roughness of Volleyball

Main investigations are focused to measurements of all forces and moments acting on the rotating volleyball, such as drag FD, lift FL, side force FS, moment of roll MX, pitch MY and yaw MZ. Based on previous first results roughness of surface is an important quantity to study. Description of measurement of surface roughness of volleyball is presented in the article. Devices used in the measurement are noted. Results of the measurement are discussed and meaning of the results for aerodynamic forces acting on volleyball is taken in consideration.