We performed experiments in which a soccer ball was launched from a machine while two cameras recorded portions of its trajectory. Drag coefficients were obtained from range measurements for no-spin trajectories, for which the drag coefficient does not vary appreciably during the ball’s flight. Lift coefficients were obtained from the trajectories immediately following the ball’s launch, in which Reynolds number and spin parameter do not vary much. We obtain two values of the lift coefficient for spin parameters that had not been obtained previously. Our codes for analyzing the trajectories are freely available to educators and students.
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We used a standard 32-panel soccer ball manufactured by Umbro, model X III 250.
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The programs at ⟨http://goff-j.web.lynchburg.edu/MathematicaAJP.html⟩ are free for readers to download and modify as they wish.
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.© 2009 American Association of Physics Teachers.
2009
American Association of Physics Teachers
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