The corresponding Reynolds numbers ( ) based on the air viscosity ν are indicated in column 6 and observed to be in the range.
We list in table 1 sports which involve balls of different diameters ( ) and different velocities ( ). Finally, knuckleballs have also been reported in cricket for a delivering speed of about 30 ms −1. In this sport, zigzag paths occur with particular balls (such as the official match ball of the 2010 FIFA World Cup, Jabulani) when kicked with no spin.
Similar trajectories have finally been observed in soccer by Barber et al. Again, this velocity is far below the maximal velocity observed in volleyball, which is 37 m s −1. Depra and co-workers measured these trajectories on a volleyball field and observed lateral deviations of the order of the ball diameter for a velocity of about 16 ms −1. Apart from baseball, zigzagging paths have been reported in volleyball and observed when the ball is launched with no spin. Despite the slenderness of zigzag motions, the randomness of this pitch explains the difficulty for batters to hit them. Nathan also determined that lateral deviations of knuckleballs are smaller than 1.2 cm which is 0.17 ball diameter.
The releasing speed of knuckleballs is far below the maximal launching speed of baseballs observed in the field (105 mph ≃ 47 m s −1). In his case, the ball is launched at a precise speed of 66 mph ( ) and follows a random angular direction characteristic of the knuckle effect. This feature is different from the one observed with Tim Wakefield, famous for his knuckleballs. Nathan et al observe that the 'normal' pitcher Jon Lester is able to send the baseball with different techniques characterized by a precise releasing speed and a precise angular direction. In this article, the authors measured the angular direction of pitches as observed by the batter as a function of the ball releasing speed for a 'normal' pitcher and a pitcher mastering knuckleballs. Despite this old history, the scientific observation of zigzag paths on a baseball pitch has only been done recently by Nathan et al. After Cicotte, several pitchers mastered knuckleballs and the pitch became a nightmare for batters. By mastering this pitch, Cicotte deserved the nickname ' Knuckles ' and finished his career with more than 200 wins. This rare event was first introduced in baseball by the Major League Baseball pitcher E Cicotte, in 1908. Among the different paths, one of the most intriguing paths is probably the zigzagging knuckleball.
El ultimo tremolo public domain free#
For example in soccer, a free kick may get around the defensive wall thanks to a side spin. Above all this looms the figure of Simoun, a powerful and extremely rich jeweller, who is more than ready to put his immeasurable wealth to use.Įl Filibusterismo is the sequel to Noli me Tangere, and cited among the reasons for the execution of the author, who is now regarded national hero of the Philippines.In many sports, players use aerodynamic effects to lure opponents and score. And the students of Manila petition the government to be taught in Tagalog instead of Spanish.įollow Basilio, a medical student and his friends as they navigate the difficult climate in Manila, while his fiance struggles with the law in their hometown. In the countryside, a group of outlaws takes things in their own hands – including the money of the rich. However, here and there are pockets of insurrection. The Philippines, still a Spanish colony, are more or less run by the Catholic friars, and with an iron fist.
El ultimo tremolo public domain download#
Download cover art Download CD case insert El Filibusterismo (The Reign of Greed)