The mystery of the swinging ball in cricket has only recently been understood from a scientific perspective. Physicists have discovered some of the secrets that make a cricket ball swing in the air as it approaches the batsman. The air flow around the ball, the speed of delivery, the angle and height of the seam and even the weather contribute to making batting difficult and bowling — when the ball swings — an enjoyable experience.
The resistance of air molecules when a cricket ball passes through the air on its way to the batsman creates what Rabindra Mehta, a NASA scientist, calls “a boundary layer” around the ball’s surface. In the ESPN article “The Science of Swing Bowling,” he says that the “boundary layer cannot stay attached to the ball’s surface all the way around the ball and it tends to leave or ‘separate’ from the surface at some point … A side force or swing will only be generated if there is a pressure difference between the two sides of the ball.” The seam of a cricket ball, or the deliberate roughing up of one side and polishing of the other, creates the variation in air flow. This variation increases the likelihood of air flow separation on one side of the ball that causes the movement in the air.
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The Average Speed of a Baseball Pitch
Baseball, known as the “national pastime,” is intrinsically linked to American sports history. The two core elements of the sport are the home run — seeing the ball sail out of the ballpark — and the strikeout. The pitcher plays a crucial role, sending down a number of pitches at various speeds. Working out the average speed requires individual analysis of each type of pitch.
Working out the average speed of a baseball pitch can be a simple equation. Add up all pitches thrown, work out the distance, measure the speeds, and you come up with an average speed. However, this does not make allowances for the variety of pitches. A fastball pitched at 90 mph is supposed to be fast, but the success of a knuckleball relies on a deception of speed and technique. Calculating the average speed for each pitch provides a fuller picture of a baseball pitcher’s skills.
The four-seam and two-seam fastballs are the cornerstone of a pitcher’s repertoire. According to Terry Bahill, in the Major League Baseball, the range of speed varies between 85 and 95 mph. The average maximum speed in 2008 — based on all the fastballs pitched throughout the full season — was 90.9 mph; the average speed at the plate was 83.2 mph.
The fastball’s closest comparison, the slider relies on a similar spin and technique to the fastball — but the late break, down and away, confuses many batters. The initial speed range is between 80 and 85 mph. The average speed in 2008, using full-season statistics and based on 104,698 sliders, was 83.6 mph. The average speed at the plate was 77.2 mph.
Sometimes known as the “hammer” or “whip,” a curveball is pitched with the opposite spin used for a fastball. The speed range, calculated to be between 70 and 80 mph, is 10 to 15 percent slower than that of a fastball. The maximum speed average, based on 72,207 curveballs in 2008, was 76.4 mph. The average speed of the curveball when it reached the plate was 70.4 mph.
With a spin and release similar to the fastball, the change-up pitch is an example of deception to confuse the batter’s timing. Slightly faster than a curveball, the change-up had a maximum average speed, based on 80,908 pitches in 2008, of 81.6 mph. The speed of the change-up at the plate was 75.2 mph.
The knuckleball, according to the “Seattle Post-Intelligencer,” has an average speed range from 50 to 70 mph. It is a rare pitch that is difficult to learn. Based on 3,760 pitches in 2008, the knuckleball’s maximum average speed was 66.8 mph; the speed of the pitch when it arrived at the plate was 60.4 mph.
Just a wonderful breakdown of the whole media narrative on the issue of Luiz Suarez. If you haven’t read this yet, and you’re interested in how the sports media works in the UK, then read this, now.
Jan 23, 2012 – Top Gear’s“lazy
Africans Mexicans” routine was broadcast to millions. It made minor news, with no repercussions. Luis Suarez’s dialogue with Patrice Evra was heard by nobody and unrecorded, but it led to a media frenzy of blaming ‘n’ shaming – with many journalists mistaking their own carelessness for a moral high horse.
The different outcomes can be explained partly by the N-word and partly by a confused application of “zero tolerance” framing, both of which featured in the Suarez coverage, but not in the Top Gear case.
BBC and Ofcom initially dismissed the Top Gear incident as category #3 – but a later BBC investigation effectively placed it…
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